Everything you ever wanted to know so you can build an EV

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ElectricGod   10 MW

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Re: Schwinn S1000 build - how to build your own EV

Post by ElectricGod » Jun 11 2018 11:26am

I mentioned in a previous post that I would redo the deck. I'll redo the battery box too. The front of the existing box does not seal up and water and dirt picked up by the front tire will easily penetrate into the battery bay. I want to stop this from happening. This is the new battery box I made for the Currie. I'll probably do something similar on the S1000, but probably make it a bit lighter weight. This thing is pretty beefy!

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This is the Currie deck. It seals around all the down tubes in the front with plywood parts that are tight fitting and then caulked in place. Between the wood pieces and the frame is also weather stripping to make a water tight joint. Even between the lid and the front section where the hinge is, there's weather stripping between them to keep water and dirt out. Mating with the frame on the underside of the flip up deck is weather stripping so seal the deck to the frame. The deck is about 4" wider that the original deck and it seals out water and dirt incursion. I will duplicate this on the S1000.

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There's even a trap door on the bottom of the battery bay. Getting at the wiring from the top side requires pulling out the batteries and then I still can't get all the modules back into their correct spots easily. My solution was to add a small trap door in the underside of the front section of the battery bay. Now I don't need to remove the batteries at all to access any of the wiring. I used brass threaded inserts so that I could remove and install the trap door repeatedly without wearing out threads in the wood. It has weather stripping under it to seal up the trap door.

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The section over the back wheel makes for a great place to strap down packages or even add a basket if desired. Grip tape really helps in keeping things from sliding around. A child could stand on the back platform. I built the whole thing with screws and nuts. There's no welding here. The back deck on the blue scooter got used many times. This one on the Currie has seen use a few times too. On the blue scooter, the back deck includes brass inserts so that I can mount a basket. I never added the inserts to the Currie back platform since I didn't use the basket very much. The back edge of the platform makes for a great place to add lights for brakes and blinkers.

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Stuff to get that you probably didn't think about

Post by ElectricGod » Jun 20 2018 4:48pm

Wire:
There's a couple of kinds of wire you will probably want to get.
1. Silicon insulated wire: You need wire that can interconnect your battery pack to your controller and other things. Wire to your controller is going to be bigger wire. silicon coated wire is made of many small strands jacketed by silicon rubber. It's very flexible wire and holds up well to abuse. It also does not burn. You can touch your hot soldering iron to the insulation and nothing happens. Direct flame will not burn it. I use various sizes depending on current load needed. 14 awg silicon is a great size for running power to a bunch of peripheral items like lights. Usually what I do is make some kind of small terminal block that has 6 positions on it. 3 are tied to batt+ and 3 to batt- and some 14 awg feeds power into the terminal block. I keep red and black lengths on hand for this sort of thing. For horn, side lights, head lights, and a few more LED options, this is lots of current handling capability. For the motor controller, I start at 10 awg. A 1500 watt controller really only needs 14 awg feeding to it, but 10 awg just isn't that expensive or that much bigger and it has much less wire resistance than 14 awg. 10 awg silicon wire can handle 100 amps easily. The Currie uses 10 awg for all the power wiring and motor phases. The wire at max power does not get warm. Phase amps can be much higher than battery amps. My phase wires do not get warm despite there being something like 100-150 amps in them pretty much all the time. I have lengths of 10 awg silicon wire in red, black, blue, yellow and green. I have some 26 awg silicon wire in lots of colors. It works well for making a balance cable, but it does not hold up well to abuse. The strands are too few to hold up to any amount of snagging and the insulation since it's so rubbery does not provide any support either. Use small awg silicon wires where they can't get snagged or suffer stress. I have some 12 awg in multiple colors, but honestly, it will get used only if I were to build a small EV such as a Lehe K1 or a mountain board.

2. Multi conductor cable: Lots of switch clusters and throttles and what not come with a long length of cable already on them. Most of this sort of thing is made in China and they tend to use cheap wire with vinyl insulation. Any heating and the wires melt. Also the insulation isn't very tough so it doesn't take abuse very well and wears quickly. Lots of stuff slides over the ends of the handle bars. If you set everything up right, then there's not lots of slack at the handle bars. If you need to slide something back off again, you need to pull wire back up from the battery bay to create slack at the handle bars to pull of the item. A better option is to use IP68 connectors. Leave a short section of wire on the switch cluster or throttle or whatever it is...something like 1 foot long. Run a single larger cable down into the battery bay that has sufficient conductors to handle all your wiring in a single larger cable. Belkin makes good quality cable. The outer insulation is tough and the individual conductors use insulation that handle heat pretty well. 24 awg, 8, 10, 12, 15 conductor are pretty common. They also include a shield that includes a conductor so realistically you have another wire in the cable. I then terminate this cable in an IP68 connector at the handle bars. The other side of the connector then splits off to the various things that need wiring into the battery bay. The one cable holds up better to wear and abuse and takes up much less space. Never mind that it's much better wire! If/when you need to service something at the handlebars, all you need to do is disconnect the IP68 connector and you can remove things easily. Some people worry about using a multi conductor cable with battery voltage in it. I've been doing this for years and years now. I run battery voltage (48, 66, 82, 130 volts) in the same cable with 12 volts and throttle signals. The individual wire insulation on a single wire is good for something like 600 volts and I have 2 sets of wire insulation before there's a problem. I think I'll be OK. Inside the IP68 connectors I need to solder wires to small solder posts. I will slide a short section of heat shrink over all the power wires before I solder them into place. It is possible that water could invade the connector and get between a power connection and something else and create a short. The heat shrink makes this virtually impossible. Yes I know rambled a good bit there. LOL

IP68 Connectors:
Most motor controllers and EV related electronics come with cheap connectors that are not water proof. This really sucks! Your EV will experience water intrusion if you use it outside. Eliminate as much of this as is humanly possible. I want to keep my connections dry and clean and weather proof. IP68 connectors are not expensive and they are readily available. I buy quite a few of this style in 6 or 8 conductor. I don't buy the cheapest ones I can find or the most expensive ones either. When they are all screwed together, the joints seal up on silicon o-rings. There's even a silicon seal around the cable. If you are running multiple wires into the connector, consider putting some silicon sealer in the wires before you assemble the connector so that you close up the small gaps between conductors. I usually do that and then slide a section of heat shrink around the wires where it will get squeezed by the green seal in the connector. I then shrink the tube which forces the silicon in between the conductors and makes a nice seal between the heat shrink tube, silicon caulk and wires. This also keeps the silicon calk away from the green seal in the connector. If you need more than 8 pins pins in a connector, you can also get larger IP68 connectors. I have several in 18 and 24 pins, but that's getting a bit ridiculous in a single connector! I use these connectors at my handle bars and at my motors and motor controllers. Halls wires go in a 6 pin IP68 connector. The 6th pin gets used for a temp sensor in the motor. All my motor controllers will have 2 on them. One is the hall connection. The other is enable, speeds and throttle. I don't use the brake or cruise functions so I don't have another connector for those, but that could be another IP68 connector. Since I use a 6 pin and an 8 pin connector, I can't connect them up wrong. If you use a couple of 6 or 8 pin connectors on the controller, then be sure to label everything so you don't make a connection mistake that could damage things. All my exposed connections where ever they exist are in IP68 connectors!!!

https://www.ebay.com/itm/8-Pin-M14-IP68 ... Sw65FXqo9w

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Bullet Connectors:
You need to disconnect your battery or controller or motor from each other. I want to have sturdy high current connectors any where I need to disconnect 2 things. 5.5mm bullet connectors are ridiculously cheap...50 cents per set. They require no tools to make up the connection. They handle 150 amps and they securely connect together and stay together. I love 5.5mm bullets! All my EV's use them to disconnect battery power at the battery packs, power at the motor controller and for the motor phases. Any large high amperage connection, gets bullet connectors. I use them for several reasons instead of XT90's, andersons and other bullet connectors. An XT90 is just a set of 4mm bullet connectors in a shell. I commonly want to disconnect +batt separately from -batt. An XT90 wont allow that. You are disconnecting everything all at the same time. Individual bullets, allow for individual disconnections. AND 5.5mm bullets can handle nearly double the current of an XT90. Anderson connectors are huge and they make spring loaded contact on a small contact surface. AS a result, 30 amp andersons are 8X larger and 5X more money than the venerable 5.5mm bullet. I pretty much use 5.5mm bullets exclusively, but sometimes I need bigger ones so 8mm or 10mm bullets have occaisonally seen use too. 6mm bullets are not as good as the 5.5mm bullet. While the diameter is larger, they don't hold together as well or handle as much current. Just get 5.5mm bullets instead. I've bought expensive 5.5mm bullets and cheap ones. I can't say the expensive ones are worth the money. They all connect together equally well and all handle current equally well. As a result, I buy 5.5mm bullet connectors purely on price. I use them for any and all large current connection! It's a tight fit, but 8 awg wire will fit in them and that's about the current limits for the connectors anyway. If anyone suggests using some other high power connector, just ignore them and get 5.5mm bullets!

https://www.ebay.com/itm/10-Pairs-5-5mm ... 0020!US!-1

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Contactors:
I might have mentioned contactors before. Another term for them is battery disconnect switches. Essentially they allow you to disconnect your battery pack from the EV just by flipping a switch or turning a knob. I recommend that everyone have some kind of contactor that is externally accessible on your EV. If the need arises that you have to quickly disconnect power, a contactor is your best friend. Having to reach inside some compartment to unplug a connection takes time you might not have! If you need to store your EV long term, a contactor is a great way to do that so you don't run down the battery just sitting there. All my EV's use a contactor that is externally accessible. I also bridge the contactor postss with a 1K 10 watt precharge resistor. I put that on a small switch as well so it too can be disconnected for long term storage. At 1K and 66 volts, that's still allowing 66mA draw through the resistor. I'll talk about the purpose of the precharge resistor in the next topic. At 82 volts, that's 82mA draw. on a 16,000mah pack, that means in about 4 years the pack will drain out. Why bother draining the pack at all when you can disconnect it completely.

I use this contactor in all my EV's. The current rating for any switch or relay is the make/break current. If the contacts are locked together, they can handle a good bit more current. The shell is compact and the contactor is inexpensive and works reliably.

https://www.ebay.com/itm/Auto-Boat-Batt ... SwkLJbKhPl

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Precharging:
just about everyone with something RC has plugged in the battery pack and seen the giant spark. This is BAD. You are scorching the connector contacts and slowly damaging the electronics. I use a precharge resistor to manage the sparking issue. What is happening is the large capacitors in the motor controller and other things are currently sitting at zero volts and they can charge up very quickly. In the process of connecting up battery power, for less than a second they are drawing an insane amount of current. This is called inrush current or ZAP!!!. It damages the capacitors and since it also creates large voltage spikes, can damage the other electronics those capacitors are there to protect. Probably the first time you connect without prechargiong, nothing will happen other than ZAP!, but do it over and over again and you will damage the electronics. Why do it at all when precharging takes care of the inrush current issue? A large 1K resistor works great. XT90 connectors can come with a spark arrestor in them. This is just a resistor that makes contact with one of the 2 battery connections before the high current connection is made. The result is that in the time it takes to make up the connection of an XT90, you have also precharged sufficiently to take away a large portion of that inrush current. A 1K resistor across the contactor posts does the exact same thing. I don't use XT90's in my EV's. They are not tough enough for my tastes among other issues. A 1K, 10 watt resistor across the contactor posts, safely precharges the EV before the contactor gets closed. Did I mention that a large resistor is very cheap? Less than $2. How much did your XT90 with spark arrest cost? Lots more than $2 I bet!
Last edited by ElectricGod on Jun 27 2018 11:21pm, edited 4 times in total.
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Soldering

Post by ElectricGod » Jun 20 2018 7:42pm

People think that soldering is easy. It is if you do a few things correctly. I've been soldering for 40 years and so I'm pretty good at it and I'm particular that my solder joints look a certain way. I often times find solder work that is really pathetic. A lot of stuff like switch clusters out of China, wiring and things hand soldered in China are horribly done. Of course they use cheap Chinese solder which I'll talk about later.

Here's a good video on soldering
https://www.youtube.com/watch?v=SFKYUi3p8zY

I have to add a few items to the video since it deals with small connections only.

1. Go to the local hardware store and get a tin of solder flux. I solder a lot...like multiple times a week and a tin of flux will last me a year or more doing just EV related soldering. It is commonly used for soldering copper pipe together, but it is your best friend when soldering wires and electronics. It is very common that a wire won't tin properly with just the flux in the solder. Dip it in the flux and then it soaks up solder like nobodies business! The tiny bit of flux inside the solder just can't keep up with all the air gaps in between wire strands. I dip any wire end in solder flux before tinning it. The tinning process goes so much better if I do. A solder pad that won't flow solder very well probably just needs a tiny dab of flux added to it. I dip switch legs, wire ends, parts legs, just about anything in flux so that I get optimal solder flow.

2. If you have a bullet connector or large hunk of copper or whatever it is, put a little solder flux on the area that is supposed to get soldered to. Then heat up that area and the solder flows much better and bonds better. If the solder makes beads on the surface, there's very likely a need for some flux to get through the oxide layer and to help solder flow. For small components being soldered to a board, I probably won't add flux to that, but just about everything else...definitely yes.

3. Everybody wastes solder. Everybody can scrounge solder from old circuit boards or other sources. It doesn't matter the source, it's just solder and you want a little blob of it sitting around. I have no idea what that solder my blob is actually made of. It's all kinds of solder from all kinds of places. I solder a lot so I have the blob I use which is about 1/2" across and then a much larger blob that is waiting to be eventually used up. A little flux on many small drops will clean up the tiny bits of solder and cause them to flow together into a large blob. Whenever you need to tin the end of a wire, dip the bare wire end in the flux, melt the solder blob and immerse the end of the wire in the solder blob. Instant tinning! If the wire won't take solder very well, dip it in the flux again and then into the liquid solder blob again. I re-use solder in this manner constantly. The same solder blob can be remelted a thousand times and be just fine. If it gets grunge in it, put a little flux on the blob and remelt it...clean solder! The above video showed cleaning your solder tip and then retinning it with fresh solder. Why waste new solder when you have a solder blob readily available? Just dip the soldering iron tip in the melted solder blob and it's tinned again.

4. When your solder cools, it should be smooth and gloosy. It should flow around the connection smoothly and evenly. Clumpy solder or solder with chunks in it or a joint that doesn't flow very well was either made too cool, needs more flux or there's oxidation that the flux can't overcome. I tend to solder hotter than most people do. I use a Hakko 936 soldering station that has variable tip temperatures. I solder too hot becasue I want excellent solder flow. It also means I need to be quick so I don't damage heat sensitive electronics and plastics.

Notice the large solder traces on the bottom of this motor controller. They are lumpy and dull.

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This is the exact same solder traces. Now they are lots smoother and more shiny. I did 2 things. The first was my soldering iron was hot enough to properly melt the solder. The second was I added a little flux to them to clean up the solder once I did get it to properly melt.

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5. In the above picture, notice how the solder is not silvery and glossy despite reflowing it with sufficient heat. it has a dull shine, but not a glossy shine to it. This is due to the metals used in the solder. The big thing these days is to use lead free solder. That's fine, but it means that the metals used need to simulate the melting and hardening points for lead and tin and the flowing and bonding characteristics of those metals. Cheap solder is made of garbage ingredients. Good lead free solder has a high silver content...like 1-2%. The silver makes the solder look glossy, but it also is an excellent bonding agent. Cheap solder can look dull becasue the metals used do not heat and cool at the same rates. Lead and tin harden pretty close to identically so they make glossy connections that do not have tiny fractures. Cheap solder will have metals that cool at radically different rates or harden at differing temperatures so the solder will be dull and rough. Looking at it at 500X you will see tiny cracks, fissures and crystal like structures in the solder. This is BAD. As metals cool, they contract. As a metal transitions from liquid to solid it contracts a lot. If the contraction ratios of all the metals and the temperatures they harden at are not similar enough the solder connection will be full of tiny cracks and fissures. Just avoid cheap solder. Chinese solder can be the worst!

This is horrible solder. I bought a couple spools of it and it's just crap. I won't be buying Chinese solder again! Who knows what is really in this supposedly 60/40 Chinese solder! There's virtually no chance it is what the label says. If I run out of good solder blobs, I'll melt down some of this and mix it with good solder for the purpose of tinning wire ends and my soldering iron tip. Otherwise, it is virtually useless in my opinion.

https://www.ebay.com/itm/0-8mm-400g-60- ... SwB-1YyKM5

It's a little more money, but this is going to be good solder that cools shiny, flows well and makes a strong joint. Of course it's made by Kester and they have been selling solder to professionals for many years. A couple more dollars for good solder is worth it IMHO. When Kester lists metal content, those are real values and you can expect good results.

https://www.ebay.com/itm/Kester-1lb-Sol ... 0020!US!-1

6. Soldering irons...just avoid the $10 soldering iron from walmart or radio shack!!! Seriously! Don't EVER buy them. They are not worth the electrical chord they come with. Don't be uber cheap. Get something decent. As a minimum, you want interchangeable tips. Avoid soldering guns. They are basicly terrible for soldering just about everything. I had one and threw it away. I didn't use it for anything.

I've had several of this style of Weller soldering iron since the 80's and they still work great. The tip is replaceable and you will want to get a few different tips depending on what you are soldering. I think I paid about $35 for them too! I eventually wore out the original tips and bought replacements. They don't see use anymore, but they are a good soldering irons.

https://www.ebay.com/itm/WELLER-WP25-So ... 0020!US!-1

Ignore any soldering iron that is chordless or that runs on a fuel. You want one that plugs in to a power source such as the wall or a controller. You want a grounded soldering iron. That means 3 prongs in the plug. I had one of those instant on soldering irons a long time ago. They have the tiny gap in the tip that you bridge with the wire or solder and then it heats up. I paid like $40 for it and used it for a couple of weeks trying to get the technique down and to see if it was worth having. In the end, I gave it to a friend and went back to real soldering irons. Trust me on this, instant on is crap. Just get a soldering iron that needs to stay hot like the above Weller or the below Weller soldering station.

If you solder a lot like I do, then it may be compelling to get a solder station. My Hakko 936 was new in 2009. It has replaced all of my other soldering irons. With interchangeable tips and a really powerful temperature range, I can solder just about anything no matter how large or small it is. I bet it's still working in 10 years.

This is a Weller soldering station. I bet it's pretty good. I've never used it, but this is not going to be disappointing.

https://www.ebay.com/itm/Weller-WE1010N ... Sw-JJaaLUS

The Hakko 936 is no longer made, but you can buy them used for around $60. Don't be fooled by the Chinese knock-offs that look like the legit product, but cost $40. A legit 936 costs about $140 new.



Any soldering iron IMHO needs several features.

1. Interchangeable tips in several differnt types...one tip does NOT do everything. This is flat out a minimum requirement in my opinion. Sometimes you need to transfer loads of heat. That's a big, wide tip. Sometimes you need to solder to a tiny area. That's a very pointed tip. For most general soldering a tip that is 1/16" wide and partly flattened works pretty well. I vary mostly between 3 tips depending on what I'm doing. I have one that's a 3/16" wide flattened tip for soldering big stuff like large wires, bullet connectors and reflowing large solder traces. I have a tip with a 1/16" wide flattened end for general soldering. I have a tip that's elongated completely round and good for getting into tight spaces like soldering to the pins in an IP68 connector. I have lots of other tips too, bu they rarely get used.

2. Variable temperature with lots of wattage is the bomb. 70 watts is pretty nice! It means that I can turn the heat down to solder something delicate and tiny or turn it way up to solder a block of copper to a 6 awg wire. My Hakko gets hot enough to melt those aluminum solder rods. I can do limited aluminum soldering with it!

3. The grip needs to stay cool. If the handle is getting uncomfortably hot, then that means you won't be holding it for very long or doing a decent solder job. I solder for hours at a time and leave my iron on for hours at a time. The grip warms up to maybe 90F.

4. A slender soldering pencil is easy to manage and doesn't hinder your soldering work. A soldering iron that is bulky (solder gun) will just impair your work. I talked about my Weller soldering iron. I actually have 3 or 4 of them in different temperature ranges.. They are much larger soldering irons than my Hakko pencil. If I ever replace my Hakko for some reason, it will have to be with something that is slender, light weight and comfy to hold.
Last edited by ElectricGod on Jun 27 2018 11:27pm, edited 3 times in total.
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Determining gear ratios

Post by ElectricGod » Jun 21 2018 1:23am

At some point you will want to know what motor RPM equates to wheel speed. I want to reach 50 mph on the S1000. What gear ratio will get me there? I'm assuming that the motor can generate sufficient torque to accelerate me to 50mph and overcome my weight, the scooters weight and wind resistance. The Alien Power C80100 gets me to just short of 45 mph on a slower gear ratio. The Revolt RV100 is a stronger motor so it won't be a problem for it to push me to 50 mph. The motor will run at about 5kw or 7hp...not bad for a 70 pound scooter!

First...a few givens for the Schwinn S1000 build...
1. Top speed of 50 mph or .83 miles every minute (50 miles/60 minutes).
2. The RV100 motor has 73kv
3. Battery voltage at full charge is 66 volts
4. Motor max RPM will be 4818 RPM (Kv x Volts or 73 x 66)
5. Tire diameter is 39.5 inches. I ran a length of wire around the outside of the tire and then measured how long the section was.
6. 1 mile equals 5280 feet or 60336 inches (5280 x 12)
7. The tires will make 1527.5 rotations to complete a mile (60366/39.5)

We need to determine wheel RPM's that equate to 50 MPH.
1527.5 x .83 = 1267.8 wheel RPM at 50 mph

That sounds like a whizzing fast tire. Keep in mind that these are not big wheels like you have on a bike. The tires are all of about 12.5" tall when fully inflated. Now you know another reason why you want good tires and wheels!!!

So then 4818 RPM : 1267.8 RPM = 3.8:1 or 3.8 motor rotations per 1 wheel rotation per minute to get 50 mph.

My Currie has the same sized tires and a 72 tooth wheel sprocket. I can't see the motor sprocket well enough to read the tooth count. At 3.8:1 that would mean a 19 tooth motor sprocket. However 219 motor sprockets max out at 18 tooth so I'm guessing that's what I have on the motor or 4:1. That means it's going to accelerate a bit better than it would at 3.8:1 and have a slightly lower top speed. It does do just short of 45mph with my 240 pounds on it so that's about right. With an 18 tooth motor sprocket and 3.8:1, that works out to a 68 tooth wheel sprocket. Looking back at my build thread for the Currie, the closest sizes I had on hand was 72 tooth and 18 tooth so that's why I went 4:1. In looking around for less than a minute, I found wheel sprockets in 68 teeth from several sources for around $15 including shipping. 68:18 is pretty darn close to exactly the right ratio to get 50 mph. I bet if I swapped over to a 68T wheel sprocket on the Currie, I'd get pretty close to 50 mph out of it on a full charge.

https://www.ebay.com/itm/RLV-219-kart-s ... .l4275.c10

If you are too lazy to do some basic math, here's a few online calculators.

http://www.csgnetwork.com/tirerevforcecalc.html
https://www.robotshop.com/blog/en/vehic ... inder-9786
Last edited by ElectricGod on Jun 27 2018 11:39pm, edited 1 time in total.
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More on solder...

Post by ElectricGod » Jun 21 2018 9:05pm

In a previous post I talked about good and bad solder.

I pulled out my 500X USB microscope, melted a blob of crappy Jinhu solder and a blob of MG Chemicals solder and a blob of the random junk salvaged solder I use for tinning wire ends. The Jinhu solder smells like hair spray right in your face when the flux burns off. The MG doesn't really smell like anything. I have to say that the hair spray smell is quite annoying! Notice that the Jinhu solder says 60/40 on the lable. This indicates that it is supposed to be 60% tin and 40% lead. The MG solder also says it's 60/40. I believe that label, but the Jinhu crap is definitely NOT 60/40!

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I photographed these 3 blobs individually under the microscope so that I could not get them confused with each other. Left to right...MG, random and Jinhu. They are all going to have some amount of flux residue on them. The amount is not relevant to how good the solder is going to bond. These are fresh blobs of MG and Jinhu and who knows about the random stuff, but I did clean it up with a little flux.

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This is the MG Chemical solder. Kester 60/40 solder is going to look just like this. It melts right, solidifies right and bonds well...like good solder ought to do. It's glossy and smooth looking even at 200X. At 500X you can finally see that it some amount of surface roughness.

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Jinhu solder at 200X is obviously crap. It also does not flow into a joint particularly well and when it cools, it is brittle compared to the MG solder. The metals in the solder do not cool and solidify at the same rates. As a result the metals that cool quicker leave openings that the other metals get squeezed into since they are still liquid. The bumpy texture is the result. At 500X you can see the rough outer surface with glossy inner surfaces. The metal hardening rates are separated even more with the metal with the lowest melting point filling in the fissures or low spots which are now shiny.

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The random blob is who knows what kind of metals and it has been used over and over again. What specific metals are in here is anybodies guess! At 200X it looks far better than the Jinhu solder does. At 500X you get to see how much the salvaged solder is lacking. You can see open cracks and fissures in the surface of the solder. It's fine for tinning a wire end or solder tip, but not very good for serious solder work.

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A bit more solder testing...

I cut off the end of this junk circuit board and then cleaned off the green solder resist with a diamond emory board and then scrubbed it vigorously with a pencil eraser. When clean, I labeled the sections 1 (MG), 2 (random) and 3 (Junhu). Then I put down 3 small spots of flux so that I could put my 3 solder blobs on them.

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I heated the solder blobs just long enough to make it turn to liquid and then removed the soldering iron. The copper underneath did not have time to get hot enough to flow the solder. All close up shots are at 100X.

The MG solder blob. Still the best looking of the 3 blobs and it's even flowing a little bit.

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The random solder blob. No noticeable flowing yet.

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The Jinhu solder blob. No noticeable flowing yet.

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Fresh MG solder with no added flux soldered to the copper. I gave the copper time to heat up so that the solder could properly bond to the copper. You can see that the edges of the solder are well bonded to the copper and it's almost like they are feathered together.

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Fresh Jinhu solder with no added flux soldered to the copper. I gave the copper time to heat up so that the solder could properly bond to the copper. The Jinhu stands vertically away from the copper and does not flow into it very well.

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The final results.

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One more test on the solder blobs. This time I'm holding the soldering iron tip in each spot for 10 seconds to get everything hot. I don't add any flux or more solder. All I'm doing is heating the old spot for 10 seconds. This is more than enough time to heat the copper underneath and get the solder to flow onto it. 100X magnification. After I took these shots, I added a dab of flux to each of the 3 blobs and then reheated them for another 10 seconds each. Since the copper and solder was already pretty clean and fresh, this did not change the flow results at all.

MG solder...the edges of the solder are flowing onto the copper very nicely.

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Random solder...the edges of the solder are flowing onto the copper about as well as the MG solder. Despite this being who knows what solder mixed together, it's far better than the Jinhu crap!

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Jinhu solder...the solder stands vertical from the copper and does not flow hardly at all. This is not dramatically different from just barely melting the solder glob. As I've said all along...poor grade solder! Even the blob is very domed. It's like the blob does not want to adhere to the copper. If the solder is still fairly hot and mostly solidified, you can break it off the copper. It just does NOT bond very well.

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Suggestions

Post by ElectricGod » Jun 25 2018 12:12pm

If anyone wants me to cover a topic, post it and I'll see what I have. I'm sure there's things I have forgotten to mention or things I didn't explain that you want to know about.
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Lets talk about fasteners...AKA bolts, nuts, washers and threading

Post by ElectricGod » Jun 25 2018 2:25pm

I don't own a welder that's worth using as it's a cheap stick welder. At some point I really want to get a decent TIG welder. Welding with shield gas and being able to control AC, DC, duty cycle and so on makes for really nice welds with out splatter and voids in the weld. After stick welding, I really hate it and refuse to settle for less than TIG.

So then, that leaves me with fasteners until I can get the welder I really want. AND I will still use fasteners no matter what. Grinding off welds is generally not a great idea when you need to take something apart, Undoing a few screws however is. Lots of things can't be welded, such as steel to aluminum so that again means fasteners (screws and bolts).

A few rules of thumb...
1. Threads in metal are almost always better than threads in wood.
2. Threads that grab only a few turns on the screw are very likely to fail.
3. If you can put threads into something do it.
4. If you can put threads into something and then have a nut behind it, that's even better.
5. Never use cheap bolts and nuts. They are made of soft steel, break easily and don't last.
6. Your safety is dependent on the fasteners you use and how well they do their job. Use good fasteners and use locktite.

On all of my EV's, there are places where screws, threaded holes, nuts and washers are perfect for the job. This is the bottom of the Curries battery bay. It is held onto the frame by 8 1/4-20 counter sunk stainless screws that thread into the frame. The battery box is wood and seals to the frame with weather stripping. 3" long 1/4" bolts were ideal for this purpose and the battery box is removable if needed.

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You can't see them since they are covered up by the controller, but the screws that hold the controller in place are 6-32 and they thread into brass inserts. Threads directly in wood don't take much abuse before they are useless. The brass inserts thread in once and never get removed. The actual screws that hold down the controller can be removed 100's of times with no loss of mechanical holding power. If you know you need screws into wood that will possibly need to be removed periodically, then I really recommend using brass inserts. They are not very expensive and come in any size you can imagine.

https://www.ebay.com/itm/E-Z-Lok-Thread ... 362b1e2365

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This is the access panel on the bottom of the battery bay. The 6 screw holes are 6-32 brass inserts. The cover that goes on here needs to come off periodically. Inserts were the only logical choice. Notice how close the inserts are to the edge of the wood. Threads into the wood would not hold up for long. The inserts provide much better support and can handle having the cover pulled off hundreds of times. The wood by itself would be getting pretty useless after just a few reuses.

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There's a variety of metals that screws and bolts can come in. Depending on what your application is, you will need to make different choices. I like stainless steel, but it isn't very strong. As a result in applications where there is minimal bending forces on a screw, I'll use stainless. In applications where you need a length of bolt exposed to sheering or bending forces, stainless isn't a good choice. The ends of this shock require about 5/8" of bolt length to pass through it and into the bolt hole in the frame. If this bolt was stainless, it would shear off after a couple of months of use. In grade 8 or better, it will last many years. Stainless in this application is a poor choice.

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In this application (holding an adapter plate to a freewheel), where there is no bending forces at all, just shearing forces, stainless can work reliably.

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This bolt was originally grade 8 and 8mm, I replaced it with grade 12.2 and 10mm. It holds the handle bars to the forks. There's literally the 1 bolt that holds all of this together. It would be absolutely disastrous if it broke while riding along at 40-50 mph! I went for the strongest bolt I could find. The handle bars take lots of lateral loading when you accelerate and decelerate and 100% of those forces are on that one bolt. Nothing short of the best and strongest steel would do in this application. I think I paid $8 each for them, but now I have lots of confidence that this will never fail or snap off. Under the head of the bolt is a large, thick washer to distribute loading in the bolt hole.

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This is another application where 12.2 bolts are used. These bolts hold the motor to the frame. They pass through 1/4" thick aluminum and into the motor. They have lots of torsional or bending stresses on them thanks to 4kw of motor power. Stainless would hold up for a while, but would eventually sheer off. 12.2 will probably never fail. These are M6 screws. I got screws that are long enough to use all the threads in the motor base. This picture doesn't show it becasue this is an early mock-up while I was still getting things fitted together, but later on, I used larger washers that are a bit thicker. The grip of the screw head is what keeps it from sliding in the slot. Also the 12.2 steel screw is holding against much softer 6061 aluminum. I needed to maximize grip and to keep the screw heads from wallowing out a hole in the aluminum. A wide thick washer distributes the screw heads pressure over more area so there's lots of grip and prevents the aluminum from deforming under the screw head.

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In this application, there's 2 M6 stainless screws that go through the frame and into the 1/4" thick 6061 aluminum. There's lots of material to make threads in the aluminum so I tapped M6 threads into it. I was more concerned about the bolt heads compressing the thin walled steel frame tube so I added washers behind them to distribute the compression forces better. There's very little bending forces on the stainless screws holding the frame and motor plate together. I could have used a single M6 screw, but just in case, I put in 2.

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This is a small bracket I made that adjusts the front brake caliper out from the axle about 1" so I could use 160mm rotors. It's cold rolled steel and it's 1/4" thick. I could have drilled out the holes and put a nut on the back side, but why bother when I have so much material to work with? I tapped it for M6 and then used a couple of grade 8 M6 screws to hold the brake assembly together. The bolt hole on the tab on the forks is elongated so I added a jam nut. That way I have the threads in the steel and a nut keeping things locked together in that elongated hole. The screw holding the top of the caliper does not move so there's no need for a jam nut.

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If you don's have any, get blue locktite. I put it on every bolt and nut and thread. I buy the larger containers of it. You are paying for packaging, not contents so bigger is better. A tiny 10ml tube costs nearly as much as 50ml bottle and won't last very long. Blue locktite will keep your screws and nuts in place. Things come lose, why have to fix something on the side of the road when it rattles apart when a little locktite would have kept it from ever happening?

https://www.ebay.com/itm/Loctite-242-Bl ... Sw8gVX-1-8

How important are these 4 little screws? Not very when it comes to the stability of the EV, but when it comes to keeping someone from casually getting access to the enable connections, it matters quite a lot! They have blue locktite behind them and soon they will be security torx as well.

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What's a jam nut? Well imagine if you put a bolt through a threaded hole and then want to make sure that bolt does not come lose. Locktite will often times do the trick, but maybe not as well as you like. I often times use threaded holes in things and then add a nut behind them on the bolt. This aluminum is 1/8: thick. It can take a few threads in it, but it won't hold on it's own very well so behind the aluminum is an added nut. It literally jams the threads in the aluminum and the threads under the nut together.

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This is another example of threads in a hole and a jam nut. The threaded section passes through a threaded hole in the blue flange, through a nut, through the 2 pieces of steel, into another nut and finally into another threaded hole on the far side. The 2 pieces of steel have holes that fit the bolt. The nuts jam the threaded section to the threaded blue flanges. This keeps that threaded section locked in place so it can't ever move. Of course there is blue locktite in all the threads.

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Sometimes you want to prevent tampering. I may leave my EV outside and chained to a bike rack for hours at a time. I want to make sure my expensive battery packs do not get stolen. As a result the covers on the battery bays are held down with security torx screws. Allen key sets are very common and getting security torx bits is not impossible, but they are probably not something that people happened to have on hand randomly. I have a small selection of security torx screws that get used for battery bays mostly.

https://www.ebay.com/itm/1-4-20-x-5-8-T ... Swa81aE3j3

Those 2 screws at the back of the battery bay have large washers on them and they thread into thick steel and the heads are security torx. The only thing I could do more is put a padlock on here to make it more secure.

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Those 2 screws at the back of the lid are security torx. It's not perfect protection. For that, "i park the scooter some place lots more secure, but they do keep out the random dishonest person looking for a quick "smash and grab".

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Lets talk about washers. This seems really obvious...flat disk of metal with a hole in it. Yes that's true, but washers are useful in many places you may not have thought of. I have washers that are exactly the same diameter as the bolt head and others that are 2-3X larger and everything in between. Oh and let's not forget thin ones and thick ones and non-steel ones. GEEZ! What on Earth for?

This is a wheel adapter and 219 wheel sprocket on the back of the Currie. It's not easy to see since all the parts are black, but there's a gap between the adapter and the sprocket. The gap is just right to make the chain line dead straight. With some generic washer in that gap, I could have gotten close, but with a couple of thicknesses of washers, I was able to dial it in exactly dead on. Washers make great spacers for small gaps!

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On the XB-502, you can see the gap a bit better. There's a couple of different thicknesses of washers in there that make this gap exactly right so the chain line is dead straight.

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Thick washers distribute clamping pressure much better than thin washers. For holding a bolt head to aluminum or to thin steel walls, a thick washer is really needed. The Currie has thick washers under all the screw heads that hold the motor to the aluminum. Thin washers have their place too. On just about all my EV's, to tune the brakes just right, there are thin washers under the caliper bolts to get the brake pads riding exactly right. I want no brake drag except for when I'm actually braking. Thin brass washers commonly work really well for this. If you need to tune a little better, brass files or sands much easier than steel to get things dead on and it doesn't rust like steel does. I have washers that are the same diameter as the bolt head. Sometimes there's plenty of support, but I don't want the bolt head galling the paint or anodizing under it. A washer of the same size protects the surface and allows the bolt head or nut to still turn and tighten up.

It's hard to see in the picture, but this axle tensioner is aluminum. The axle nut has a washer under it that is just barely larger than the nut. I can tighten and loosen the nut 100 times and never damage the anno on the tensioner.

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This is the blue scooter and there is not a washer under the nut. Notice the circle galled into the anno on the tensioner from the nut.

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Awe nuts! Yup...lets talk about nuts. Haha. There are basically 3 kinds that I get. Everybody is familiar with nuts that include a nylon bushing in them. IF you have something you need to put on once or twice and have the nut stay put, the these are a decent choice. After that the nylon is usually gone and you might as well NOT have the nylon at all. I have nylon nuts, but honestly, I'm going to add locktite becasue I don't trust the nylon to do it's job for very long. Thin nuts vs thick nuts. Sometimes the space is tight and you can't add a 1/2" thick nut, but a 1/4" thick nut will fit in the space. A thin nut is better than no nut. Thin nuts have like 3 or 4 threads in them. They can't take any amount of serious tightening like a much thicker nut can. Use a nut that has sufficient threads to hold reliably. This is commonly why I'll use a jam nut on the back side of something that also has been threaded. Nuts also make great spacers. I keep a few 1/2" nuts around for this purpose. Every body needs to get the side to side spacing of their wheels right between the forks. Sometimes you need just a washer. Sometimes you need 1/2 or so. A large nut drilled out to fit over your axle might be just the thing. I've used large nuts on many axles to get the wheel centered between the forks.

This isn't exactly what I'm talking about becasue I found an axle spacer that fit, but imagine that smaller spacer was just a bit shorter. A 1/2" nut could have fit in there instead. Look behind the brake rotor, I used nuts and 2 washers to space the rotor away from the wheel hub a little to get the caliper lined up.

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Conclusion:
1. Get a tap and dye set
2. Get bolts and screws that are strong enough for the job
3. Get a variety of washers and nuts that can be used for various things
Last edited by ElectricGod on Jun 25 2018 4:14pm, edited 1 time in total.
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Chain tensioning

Post by ElectricGod » Jun 25 2018 2:34pm

You don't want slop in your chain. You want the chain tight enough so it doesn't slap around or jump off the sprockets. You also don't want it so tight that you can play a tune on it. Get it so there's a bout 1/4-1/2" of movement on the long section.

There's devices that take up chain slop. They are called chain tensioners. They are not to be confused with axle tensioners or devices used for properly aligning the wheel with the frame. I'll talk about axle positioning devices in my next post.

These are chain tensioners. They remove slack from the chain and that is ALL they do. You will notice they have nothing to do with the wheel axle or chain alignment.

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Any kind of chain will grow slack in it as it stretches. Any chain with insufficient tension will skip over the sprockets and wear down the teeth prematurely. 219 is no different. 219 since it has no side play in it needs slack to get it on and off the sprockets. Under tension and in a dead straight chain line without slack in the chain it's very hard to get 219 chain off without damaging something.

On the blue scooter, I used a ready made chain tensioner that I modded to hold the chain tight. I can loosen those wing nuts and loosen or re-tension the chain in about a minute if needed. I don't use the spring tension behind the roller. It's not strong enough to deal with regen. I lock the slider down where it's pulling the chain tight enough to not matter.

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The Currie is a bit harder to set chain tension. The motor slides in vertical slots when its 4 bolts are loose. All the way down, allows for enough slack to get the chain off the wheel sprocket. Pull the motor nearly all the way up and the chain is under tension. There's about 1/2" more room in those slots for more chain stretching.

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The XB-502 has a roller that is attached to a sliding block. Loosen a couple of bolts and the whole mechanism can slide about an inch in either direction. The slots are a bit longer than this in the finished chain tensioner.

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Drive side vs return side:
Chain is a pulling machine, not a pushing machine. It's not a lot different than trying to push string. The section of chain that pulls the back wheel around as you go forward is the drive side of the chain. That's usually the top of the chain path. The section of chain that usually has some slack in it and is just making the return trip is the return side. Why does this matter? In the Currie it doesn't matter terribly since there's just pulling the motor tight. There's no separate chain tensioner. The drive side and return side are under pretty much the same amount of tension. When using a chain tensioner like the blue scooter and the XB-502 have, you never want to put it on the drive side. This creates lots of reliability issues and the tensioner needs to be engineered to handle the maximum load forces on the chain. The return side by comparison is not under load and so the tensioner can be fairly light weight. All it has to really do is soak up chain slop and deal with regen forces which are far less than drive forces.
Last edited by ElectricGod on Jun 25 2018 5:46pm, edited 3 times in total.
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Axle tensioners or axle allignement devices.

Post by ElectricGod » Jun 25 2018 3:45pm

There's these devices that you put on your axles that people commonly refer to as chain tensioners. They get misused to tension the chain...just DON'T! This is a bit of a "soap box" item for me so here goes...getting on my soap box now,

In the previous post, I talked about chain tensioners...REAL chain tensioners...devices specifically for removing slack from the chain. They don't align the back wheel and they don't align the chain. They literally have nothing to do but remove chain slack.

The devices that go on either side of your axles are not there to soak up slack in your chain. Their one and only job is to get the back wheel dead straight in the back forks. Do NOT use them for taking up chain slack. Set them for dead nuts lined up back wheel and lock them down. That is their only purpose.

I use 219 a lot and it does not bend at all. It has zero tolerance for going sideways around curves. Make the chain line dead straight or just don't bother. For bicycle chain you can slop around and not care. For higher power chain commonly used for KART, mopeds and motor cycles that's just not an option. You need dead nuts straight chain lines...period!

An EV of any kind is multiple systems built together to make a workable and reliable whole. You want to build on systems that are stable and reliable and always work the same way. If you use your axle alignment devices to pull out chain slack you are taking the most basic part of your EV (driving the back wheel) and throwing it out the window. You simply MUST HAVE dead straight chain alignment that never changes. That means set the axle dead straight in the back forks and don't mess with it again. Put blue locktite on the threads and lock down the jam nuts and then NEVER EVER mess with the axle alignment devices again. Did I say it enough yet. They align the wheel in the frame to get it dead straight. They do NOT EVER remove chain slack!!!

These are axle alignment devices. They are NOT chain tensioners despite the misleading name commonly applied to them.

The device under the axle bolt is setting axle alignment only. Their sole job is to get the back wheel dead straight in the forks.

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In the Currie, you can't see them, but between the axle bolt and inside the drop-outs is a chunk of aluminum that is exactly the right thickness to exactly align the back wheel. They are flat out NOT adjustable at all except via filing on them. This of course is perfect since you set them to dead straight wheel alignment and never mess with them again.

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The wheel alignment devices on the blue scooter.

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On both sets of adjustable axle alignment devices shown above, once the rear wheels were dead straight in the forks, they were locktited and the jam nuts were locked down. They have not EVER been moved since or been readjusted except if I saw that I didn't have the back wheel quite aligned dead straight. Everything else in the drive line depends on these alignments NEVER moving again.

Implications of messing with rear wheel alignment...

1. You've just ruined the chain alignment which you WANT to be dead straight and unchanging.
2. Your EV no longer tracks straight. The back wheel is offset from the front wheel. The 2 wheels no longer ride exactly in line.
3. The back tire is constantly scrubbing sideways a little and wearing excessively as a result.
4. Your chain jumps off the sprockets at random since it is no longer tracking straight.
5. You stress one side of the chain more than the other since the chain is pulling slightly off from dead straight through the sprockets.
6. You prematurely wear out your sprockets. 219 sprockets ought to last at least 10,000 miles if not a lot longer. If your sprockets are half worn out in 200 miles, there's an alignment problem.

Take it from someone that learned this lesson the hard way. I wore out sprockets, broke chain, jumped off the chain...basically killed my EV's reliability becasue I used the axle alignment to tension the chain. Just DON'T...that's what chain tensioners are for! If you are still unclear, go reread my chain tensioning post.
Last edited by ElectricGod on Jun 28 2018 12:21am, edited 1 time in total.
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Machining in your garage

Post by ElectricGod » Jun 25 2018 6:58pm

People think that you need a machine shop do lots of stuff. A mill or lathe will make more precise parts and do certain tasks much faster than you can do them, but you don't really need a lathe or mill for most things.

This 1/4" thick 6061 plate was all done with a drill press and files.

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I started with this cardboard mock-up. This is the 3rd one. The first 2 were not really what I wanted. The dark areas are super glue soaked into the cardboard. I can then file on the super glue soaked cardboard to get the hole sizes just right.

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Once the cardboard mock-up was correct, transferring that to aluminum was easy...just trace with a sharpie.

A lot can be done with a small drill press. Get the drill table exactly 90 degrees from the drill bit and you are well on your way to doing a lot of basic machining for cheap. Where ever you want to drill a hole, don't just drill there. Drill bits wander around until they get into the material a little. Get a nail punch with sharp point or a center punch to mark the metal where the bit needs to land. This will help stop bit wandering so your holes are actually where you want them. The spring loaded ones are really cheap and you can operate them one handed.

For elongated slots like in that aluminum plate. I marked out with sharpie where the slots would go. Then I marked evenly spaced marks with a center punch where I wanted to drill. Then I drilled a line of holes that over lapped a little. This clears out 85% of the metal to make the slot. Then I carefully filed out the rest of the material until I had the right sized slot. The entire slot was done with a wood shop square, drill press and files.

Cutting the square can be done without machines too. I have a cheap band saw that I've owned for close to 15 years. I rough cut the square on the band saw. It's slow and you can't feed very fast, but that's still better than doing it by hand. If you don't have a band saw, then a cross cut carpenters saw works pretty good for cutting aluminum. I have a table saw. I look for the flattest edge on the metal and then using the miter guage, take thin skims off another face. It is important that you go slow so that you don't jam in the saw blade and send your piece of metal flying off. Once one side is flat, now you have a reference side for trimming the 2 sides 90 degrees to the reference face. Make skimming cuts until they too are flat and square. IF you did it right, you now have 2 sides that are parallel and perpendicular to a third side. Trimming the 4th side should be easy. If you look on the above pictures you can see diagonal marks in the edge of the metal. This is the saw teeth cutting marks. A carbide blade is your best bet. Never do this with the rip fence. Wood caught between the saw blade and fence is pretty dangerous and if it hits you, it's going to hurt. Trapping a piece of metal between the blade and fence is deadly. It's going to fly out of the saw like a spinning knife! It's going to send you to the hospital. Using the miter gauge, makes catching the metal and turning it into flying death virtually impossible. I cut aluminum on my table saw pretty often with the miter gauge. If you don't have a table saw, a radial arm saw will work too. If you don't have either of those, then filing will get you there too. Make one edge flat and then use a woodworking square to make lines with a sharpie for the perpendicular sides. The final side is then made from one of the perpendicular sides. It's filing, but if you are careful, you can make really good and flat surfaces. No major tools required beyond a vice, files and a hand saw.

This little part reinforces the motor shaft to the bell and was done with a vice on my drill press. The disk was originally the prop adapter that came with the motor. I cut off the bottom part and then laid out lines on it to find dead center between the screw holes. All I used was a carpenters square. Once I knew where the 4 holes were around the edge of the disk, I used 2 identical drill bits in the existing screw holes to align the disk edge up and the spot for hole in line with the drill bit. A center punch kept the bit from wandering and I drilled out 4 holes around the edge of the disk. Is there better ways of doing this? Sure there is. There's a great tool for using with a mill that does a far better job, but it costs a few hundred dollars for just the tool. My method needed no special tools other than a drill press and it's close enough to not matter.

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Last edited by ElectricGod on Jun 28 2018 12:25am, edited 1 time in total.
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Re: Schwinn S1000 build - how to build your own EV

Post by armandd » Jun 26 2018 3:58am

Very informative! Thanks a lot for sharing all this.

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Re: Schwinn S1000 build - how to build your own EV

Post by ElectricGod » Jun 27 2018 11:48am

You are welcome!

I made this thread for people who are wondering how to do things on a shoe string budget or have questions on how to build something.
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RV-100-regular outrunner

Post by ElectricGod » Jun 27 2018 1:31pm

Shipping from Isreal by ship is VERY slow! China by ship commonly takes close to half as long. I ordered this motor from Revolt (made in Isreal) in mid May. It arrived yesterday...45 days later. If you want it fast from Revolt don't ship by sea! I bought from this exact URL.

http://www.revolt.org.il/sale/rv-100-regular-sale/

I figured what better way to get to know Revolt than to buy a random motor that's on sale. If I found the motor was garbage I'd be out $170 and at worst, I'd put it up for sale. I've spent lots more than that over the years on EV stuff that I'll never use so I saw it as a reasonably worth while risk to take. I have just a few pictures of the motor so far since I picked it up from the post office on my way into work this morning. I'm mostly impressed so far and the pictures are at the bottom of this post.

Complaints:
1. The phase wires are 12 awg silicon. I wish they were 10 awg silicon.
2. The motor comes with shielded bearings, but talking to Revolt, they were more than willing to install sealed all steel, sealed hybrids or all ceramic bearings.
3. No motor base or prop adapter.

Things I really like:
I thought getting what I considered "less than optimal" out of the way first was the best plan since there is really not very much to say negatively about the motor.

1. I have have previously compared the RV-100 motors with Alien Power C80100's. I now see that was a mistake. This "low end" Revolt motor is a much better product than the AP motor.
2. The stator is bigger. The specs say 85mm, but there's no way this is a mere 5mm larger than the C80100 with it's 80mm stator. I've never measured the C80100 stator, but if this is 85mm, then AP is lying and their stator is more like 70mm.
3. Bigger stator teeth, bigger magnets. These magnets look to be about 16mm wide. I believe the C80100 magnets are 11mm wide. Length and thickness look about the same.
4. The stator is wound with 18 awg wire. The C80100 with 32 awg. The windings are tight and even and the stator teeth are 100% full.
5. The stator looks like it's soaked in epoxy.
6. The outer bell shielding is better. I used an allen key. The C80100 grabs steel objects quite strongly. This motor does attract steel, but not as much as a C80100.
7. The C80100 is rated for 7kw. I knew buying the motor, that was highly unlikely as anything other than as a maximum value. 80mm stators typically max out at 5kw. My C80100 does pretty much exactly that. The RV-100 is rated for 2kw continuous and 5kw peak. I'm pretty sure those values are waaaaaay under rated based on what I'm looking at. This stator is much larger. I bet 6500 watts continuous is likely.
8. Same sized shaft (12mm), but this one has 3mm key ways on both ends. Supposedly the shaft to bell union also has a 3mm key in it.
9. The motor is a good bit heavier than a C80100. I won't know for sure until I actually hold both motors in my hands, but I'll give it an extra 2-3 pounds of mass. That's probably 80% from a larger stator.
10. Motor height is probably very close to the same, but diameter of the armature is a good bit larger on the RV-100.
11. There's no gaps between the magnets. They use 100% of the space available inside the motor bell. Too bad they are not curved, but that's reserved for the RV-100E.
12. Rating Revolt specifically, they are quick to respond to emails (within a few hours) and questions are usually answered completely. I can't say that has ever happened from Alien Power. With AP, ask a question and wait 3 days and never get a complete answer so you end up asking repeatedly and waiting repeatedly. My last transaction with AP was less than positive. It took 2 months of reminding them to send me all my parts before getting everything! GRRRR!

Conclusions:
The Currie scooter is very strong and it tops out at 45 only becasue I don't want to gear it faster. The motor has plenty of torque to get me to 45 mph. It's geared at 4.1:1 or 74:18. If I dropped that to 70:18 or 3.9:1, I'm very confident that 50mph would be doable...exactly like my calculations done above. With the RV-100-regular motor on the Currie, it would be MUCH faster and stronger than it already is. I suspect I'd deliberately turn down the phase amps just to make it less strong. This of course is exactly what I hoped for on the Schwinn build. It's a bit heavier and a bit bigger despite the exact same wheel size. Despite those things the RV-100-regular will probably still give me more acceleration and top speed than the C80100. This motor can honestly run a much larger EV without trouble. There is no doubt in my mind of this and all I've done is look at the motor. What's more is this is the weakest model in the RV-100 line-up! I think I'll seriously look at getting an RV-100E soon...just for comparison.

A few pictures...more will come later when I take the motor apart and use a better camera.

Image

The holes tapped around the perimeter of the bell top and bottom have small set screws in various places for balancing. Alien uses globs of JB weld epoxy between the magnets inside the bell for balancing. This is much better!

Image

Image

Cell phone cameras pretty much suck. I took this picture multiple times before I got one I thought was passably OK. Those stators are 100% full of 18awg copper.

Image


Lets look at the C80100 for comparison. I still like this motor a lot, but by comparison to the RV-100 base model...well it's just not as good.

Much less copper fill per tooth. I'm going to estimate 75% full and it's wound with 32awg strands. The gaps between the teeth is 2-3X larger.

Image

The stator looks like it's coated in epoxy, but the wire is not.

Image

Smallish magnets with large gaps between them.

Image

This is what I do to the AP C80100 to make the stator hold up to the weather...give it a good dose of electrical paint!

Image

I do wish the RV-100 had 4 screw holes in the top like the C80100 does. There's a good chance that people will want to use the motor with a propeller.

Image

I want a kit like this with the RV-100 and there's nothing at all. I did strongly recommend adding something like this to the RV-100, but they said people typically didn't want a universal kit. I disagree. They should make it at least as an add-on kit that you buy separately.

Image
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Re: LED lights

Post by ElectricGod » Jun 27 2018 9:51pm

Addy wrote:
Jun 06 2018 7:10pm
ElectricGod wrote:
Jun 06 2018 6:01pm
The weird part is they run on 8.4 volts. That's 2 lithium cells in series. The light itself is well made, but you can't run it on 12 volts. You will need another DC-DC converter to drop down to 8.4 volts.
Have you tried running it with 12V? I bought a similar light from amazon which came with a 2s2p lithium pack. I tested it with my bench supply, slowly raising the voltage up to about 13V. It still worked totally fine, the wattage remained about the same. I use it on my ebike and I bought another for my friend's ebike.

http://www.amazon.ca/dp/B00CGUL65U
Hi Addy,

I did...ran one of them at 12 volts and burned out most of the LED's in less than a minute. That's Chinese LED's for you! Legit CREE parts are lovely things and will run at well over their voltage specs and make crazy amounts of light in the process.
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Re: Everything you ever wanted to know so you can build an EV

Post by Dui, ni shuo de dui » Jun 28 2018 2:05am

Great thread, this should be a sticky!

I just disagree with what's been said about LiFe in page one, but I guess the less people buy them the cheaper they'll remain in 2nd hand market, so good for me! :lol:

Keep up the great work!

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Re: Everything you ever wanted to know so you can build an EV

Post by ElectricGod » Jun 28 2018 10:26am

Dui, ni shuo de dui wrote:
Jun 28 2018 2:05am
Great thread, this should be a sticky!

I just disagree with what's been said about LiFe in page one, but I guess the less people buy them the cheaper they'll remain in 2nd hand market, so good for me! :lol:

Keep up the great work!
You are entitled to your opinions. Why do you find LIFE batteries compelling?
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aligning your back wheel and checking if your wheels are worth it or not

Post by ElectricGod » Jun 28 2018 12:21pm

I've talked about it and the devices that create and maintain back wheel alignment, but not talked about actually aligning your back wheel.

You need several items:

1. Your EV. If the back wheel has a chain on it, take it off
2. Some wrenches to loosen the axle bolts and to loosen the axle alignment devices.
3. A long dead straight, stiff yard stick that won't bend. A steel yard stick works well for this. It needs to be long enough to span the diameter of your rear wheel and reach the frame in front of the wheel.

Lets pretend that you have never messed with the axel alignment and that what you have is the "factory set up". I've seen some really good rear wheel alignment and some really awful alignment. Let's test it out to see if it's good or not.

1. Lift your EV's back wheel off the ground so it can spin freely without you needing to hold it up.

2. Spin the back wheel by hand. Do you see any wobble in the rim? I don't care about the tire so much. A lot of cheap wheels are poorly machined and the bearing holes in the hub are off center. This creates wobble in the wheel. I have an uber cheap cast wheel that is deformed in the rim area. The axle bearings are good, but the rim is really bad out of round. If you have anything like this, you will want a new wheel. If you think there is wobble, but not sure, you can spin the wheel, and rest a permanent marker firmly on the rear frame so its tip just grazes the side of the rim. The marker will leave a line where it grazes the rim. If the rim wobbles side to side, there will be spots where there is no marker on the rim. This is bad.

Note: If you need new wheels and it is VERY possible that you do, then I can do another post on wheels I know are good and still cheap. If you look at my EV's ALL of them have the original wheels at least partly replaced. Poor grade wheels are super common and they ruin ride quality and control. I'll also add brands of good tires. Bad tires suck, good tires don't.

3. If the tire wobbles a lot and the rim wobbles just a little, it is possible you have a malformed tire that is pulling the rim out of round. This is a bit painful, but it's important to have nice round wheels otherwise ride quality and control of your EV will suffer. I want you to live and to not die so lets get the EV riding on good wheels! Get some tire bars, deflate the tube and pull the tire and tube off the wheel. Repeat step 2. When you get down to step 11 you will want to take the tire off anyway so this is probably a good thing no matter what. Also, you want to go tubeless and that means removing the tire as well. Might as well kill as many birds with the same stone as possible.

4. If after removing the tire your rim no longer has side to side wobble, lets check if it's round too.

5. Spin the bare wheel. Put the marker tip on the lip of the rim so it just grazes. Look for places where there is no marker on the lip. If this is just very small spots, I wouldn't worry too much, but if you have a 2" section or more where the marker does not graze the rim, then you probably ought to think about replacing the wheel.

6. Side to side wobble or out of round are both going to really hurt your riding experience and control. Better wheels are going to solve this problem. I seriously doubt you can "fix" your existing wheels wobble or out of round issues.

7. Pull the wheel off the forks and turn the axle bolt in your fingers. Does it turn smoothly and freely? If you feel spots while turning the axle where there's a crunching or binding feel, then there's a really good chance your bearings are shot. Might as well replace them while you have the wheel in your hands. They won't get better on their own and will only create added friction and eventually fail completely. See my previous post about bearings and replacing them.

8. OK...one more test. Stand the wheel on one end of the axle bolt on a hard flat surface. If the wheel is balanced, you should get it to stand on its own on the bolt end. If you spin the wheel a little, there should be no wobble. If it's not balanced, then get a bunch of pennies or washers and some masking tape. The wheel will probably always fall over in the same direction...towards where it is heaviest. Tape a washer to the side of the rim opposite of this spot. See if it balances and spins without wobble. It takes some trial and error to get it right. Sometimes you add too much weight, sometimes not enough, sometimes you add it in the wrong place. Worst case scenario you can always remove all the taped on weights and start over. Now you know where the light and heavy spots are in the rim. Get some wheel weights in a few different masses such as 1 gram, 2 gram and so on. Ebay has them in a zillion sizes and weights for uber cheap. They stick onto the rim. attach the correct weights to the rim in the appropriate places and then spin it on one axle end again. Get the wheels to the point where they don't wobble anymore.

9. I'm assuming you now have round, wobble free and balanced wheels. I don't care about balance so much for alignment, but wobble or out of round are going to cause alignment issues since the wheel sprocket mounts to the hub on the wheel. Don't continue if you don't have good wheels. You won't get good results.

10. We need to make sure the wheel is centered side to side between the forks. I've seen it several times where the wheel is 1/4" to 1/2" closer to one fork or the other. Commonly the hub on one side will be a little longer than the other side of the hub. You can't use the hub ends to center the wheel. You can use the center of the hub which should also be the center of the rim. Use the yard stick or tape measure to measure both sides of the hub center to inside surface of the fork. This distance should be the same on both sides. If it's not, adjust the axle spacers, add a washer as need to the axle, etc to get the wheel centered properly.

11. Now we can actually align the back wheel. So far we have not done anything to change the existing setting of the 2 axle alignment devices. Put the wheel back on the forks with the alignment adjusters installed and in place. Tighten the axle nut enough to hold things in place but just barely. Put a mark dead center in the frame in front of the back wheel. This will be what we reference for alignment. Put the steel yard stick across one side of the rim. Look at where the far end of the yard stick lands on the frame. Put a small mark there. Do this again on the opposite side of the rim. Are the 2 marks equally spaced side to side on the frame? Do they center in the frame? If they don't, the alignment adjusters are set wrong. We want the back tire tracking dead inline with the front tire. That happens by getting the back wheel dead inline in the frame. If your alignment devices have jam nuts or some other locking mechanism, loosen just one side. Turn the adjustment nut or bolt in or out a little until you get the wheel dead straight with the frame. Check it with the yard stick again. Get the alignment dead straight. Once it's there, now you can lock down the loosened alignment device. Put some blue locktite on the threads and lock it it down so it can't change position ever again. If yours don't have jam nuts, they may have drifted out of position. ADD jam nuts so that can't happen anymore.

12. So far we have ignored everything else that depends on the wheel alignment. It is possible that your brakes drag now or something else now needs adjustment. Fix those things, BUT leave the wheel alignment alone! WE are building a complete EV. It's one subsystem built on top of another. Probably what ever is now out of adjustment was done the way it was becasue someone didn't know what the real underlying problem was to begin with. You fixed all of them...bad wheels, bad tires, non-centered wheels and bad wheel alignment. I can't help that one bad subsystem effects everything else. It's now fixed. Adjust the other sub systems that are built on top of it to account for proper set up.
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Getting the motor and wheel sprockets lined up

Post by ElectricGod » Jun 28 2018 1:08pm

I'm replacing my motor for one that's much stronger. This means that I'll need to make some sort of bracket that is also much stronger that will hold the motor in place. The bracket need to be parallel with the front and back wheels which are now in a dead straight line with the frame. If the new bracket is canted off from parallel, then the motor sprocket can not be lined up with the rear wheel sprocket. 219 chain does not bend side to side and it will eat sprockets for lunch if they are not dead parallel and inline with each other. Do it right and the sprocket and chain system will be highly reliable and last for many thousands of miles. Do it wrong and it's a nightmare. There's not much grey area in between.

1. Make your motor bracket dead parallel with the wheels and frame.

2. Now your motor when mounted to the bracket has it's shaft exactly 90 degrees from parallel with the frame and wheels. This is exactly what you want.

3. Put the sprockets on the motor and back wheel. They had better be dead parallel right now. That yard stick placed against the wheel sprocket will tell you this. If not, you didn't do something right. Wheel alignment and bracket placement are the issues here. They are probably NOT parallel with each other and parallel with the front and back wheels and the center of the frame. We need to verify they are parallel right now. Fix the problems before continuing.

4. Remember we are building one subsystem on top of another. What ever you do wrong early on effects everything else that depends on it. Fix the underlying problem instead of trying to adapt to a bad set up. You will thank me later!

5. Now everything is dead parallel. We can move on to getting the motor and wheel sprockets dead inline with each other.

6. It is possible that the motor sprocket needs to be flipped over or slid in or out on the motor shaft a little to get the sprockets dead inline, but I doubt it. It's more probable that you can get things closer to dead straight in line with this, but that you also need to adjust the wheel sprocket in or out some as well. Washers make great spacers. Space the wheel sprocket in towards the rim or away from it to get things lined up. There will be some trial and error here until you find the correct placement of the sprockets and spacing where everything lines up perfectly.

7. I assume you now have checked with the steel yard stick that both sprockets are dead inline and parallel with each other.

8. Break the 219 chain so that you have a loop that's just big enough for a little slack to take the chain on and off the sprockets.

9. Put it on the sprockets without breaking the chain again.

10. Turn the wheel slowly by hand 10 or 15 rotations forward. Does the chain stay on the sprockets? Does it occasionally climb up the side of a sprocket? Do you feel tight spots as you turn the wheel and easy spots? Does the chain come off the sprockets? These are all signs that the sprocket alignment is NOT dead parallel and dead inline. Fix as needed...you probably missed something. Forward rotation simulates motor drive.

11. Turn the wheel slowly backwards 10 or 15 rotations. Does the chain stay on the sprockets? Does it occasionally climb up the side of a sprocket or tooth? Do you feel tight spots as you turn the wheel and easy spots? Does the chain come off the sprockets? These are all signs that the sprocket alignment is NOT dead parallel and dead inline. Fix as needed...you probably missed something. Reverse rotation simulates regen.

12. The chain sound forward or backwards should sound exactly the same and not have popping or crunching sounds and generally be very quiet and smooth when turned by hand.

13. it is possible that you get everything lined up perfectly, but the chain gets tight sometimes and loose other times. The wheel sprocket isn't centered on the wheel. I've had this problem on the Currie and XB-502. Take the chain off the back sprocket, spin the back wheel slowly until you see where the sprocket is not centered. Loosen the bolts that hold it in place and push the sprocket in the opposite direction. Tighten the bolts. Repeat until the wheel sprocket is centered on the wheel as close as possible.

14. Spin the tire quickly by hand forwards and backwards. It should still sound smooth and quiet with no crunching or popping. Look at the sides of the teeth on both sprockets. Do you see scratches forming? Guess what? Alignment isn't as good as you think.

15. Up to now, don't bother adding locktite to anything. Things are still getting zeroed out. You can now locktite all the sprocket screws and tighten them down. Chain alignment ought to be ready to go.

16. Time to add the chain tensioner! One more system added on top of another.
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Re: Everything you ever wanted to know so you can build an EV

Post by Dui, ni shuo de dui » Jun 28 2018 9:27pm

ElectricGod wrote:
Jun 28 2018 10:26am
Why do you find LIFE batteries compelling?
-almost fool prof, it's almost impossible for them to burn or explode. (A charger could go nuts, a BMS can fail, even on the best packs so it is nice to have an extra layer of safety, especially if you charge at home every night).
-Great discharge rate
-Very durable
-I prefer the pouch cell package over 18650s, less part count=less things that can go wrong
-not so much of a price difference if you consider the fact that they do not lose capacity overtime as fast as the other chemistries will.

The only thing I don't like is the fact that they are a bit heavier and bulkier.

But sorry for the digression, the point of my previous post was not to start this debate but to congratulate you for this nice and informative tutorial. I wish someone made that kind of thread when I was trying to learn and understand all that stuff in the beginning :)

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Re: Everything you ever wanted to know so you can build an EV

Post by ElectricGod » Jun 29 2018 11:05am

Dui, ni shuo de dui wrote:
Jun 28 2018 9:27pm
ElectricGod wrote:
Jun 28 2018 10:26am
Why do you find LIFE batteries compelling?
-almost fool prof, it's almost impossible for them to burn or explode. (A charger could go nuts, a BMS can fail, even on the best packs so it is nice to have an extra layer of safety, especially if you charge at home every night).
-Great discharge rate
-Very durable
-I prefer the pouch cell package over 18650s, less part count=less things that can go wrong
-not so much of a price difference if you consider the fact that they do not lose capacity overtime as fast as the other chemistries will.

The only thing I don't like is the fact that they are a bit heavier and bulkier.

But sorry for the digression, the point of my previous post was not to start this debate but to congratulate you for this nice and informative tutorial. I wish someone made that kind of thread when I was trying to learn and understand all that stuff in the beginning :)
It's OK...no debate is happening. You are more than welcome to use LIFE if you like. You are right...LIFE batteries are VERY safe.

I just don't see any need for the safety margin they provide as explained below. If I'm buying into LIFE for the safety factor, then I probably already have that in several places.

1. The point of a BMS is to protect the battery pack. I always recommend people use a BMS for any lithium battery technology.
2. My charger is set to the voltage of the pack when it reaches full charge. For a 20S LIPO or LION pack, that's 82 volts. I literally can't over charge the batteries. Hopefully everyone out there is doing this.
3. The motor controller has limits. I use smart controllers only. They have max and min voltage and max current settings in them.
4. LIPO is about as "dangerous" as a gas powered engine. I bet there are many billions of gas powered devices on the planet. The number of exploding engine or gas tank related deaths and accidents is ridiculously low. Gas power with a few basic safety precautions is very safe and low risk.
5. LIPO or LION are at least as stable as a can of gas. The batteries themselves are inherently stable. They don't explode just sitting there.

That's already LOTS of safety margin IMHO. I just don't see a need for LIFE batteries and the overkill of safety they provide. However the technology does exist and they are not horrible like SLA batteries. If people are worried about the very small chance of a possible battery fire, by all means those people ought to use LIFE. The rest of us who have half full gas cans in our garages and lots of gas powered devices are already living with that level of risk that LIPO and LION provide...nearly none at all with a few basic safety precautions.

Thanks for the positive comments about the thread. I agree with what you said. I too wish something like this existed a long time ago. When I got into EV's, I was somewhat lucky. I had been messing with electronics since I was 9 years old. I went to college for electrical engineering and worked many years doing electronics repair. Much of EV's was not new knowledge to me. Still, despite that, there were lots of things to learn and I did a lot of reading and exploring and making mistakes. I have spent many hours testing and reading and making things to see what works best. What is presented in this thread is hopefully all the good parts of what I have learned all in one place.

Pouch batteries...I have 200 LTO pouch cells that will be made into 131 volt packs soon. I also intend on making an LTO car battery out of a few as well. SLA's just are awful...time to put LTO tech in my car. I'm somewhat leery and skeptical about buying used LION pouch cells. They are common to the Leaf and other cars, but I can't really know how much use they have seen. If I could get those cells new and at a reasonable price, I'd definitely consider using them. If you know of where to buy them new, please post it here.
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dual voltage systems and documentation

Post by ElectricGod » Jul 02 2018 4:01pm

I've talked about this previously in various ways, but I thought it good to bring it up as an exclusive subject.

I've mentioned 12 volt lights and how available they are.
I've talked about DC-DC converters and presented several examples of them.

Lets talk about implications and requirements of a 12 volt system in addition to a high voltage system.

1. you will now have a slightly more complicated electrical system. Not a lot more complicated, just slightly more complicated.
2. You now have part of the EV running at 48, 66 or 360 volts and part that runs at 12 volts. Every modern electric car (Tesla, Leaf, whatever all use a dual voltage system). All good quality electric mopeds and motor cycles use a dual voltage system. I have 2 mopeds that came from the factory dual voltage.
3. dual voltage requires tht you pay attention to what voltage is appropriate for that system. 48 volts applied to a 12 volt circuit will kill it. 12 volts applied to a 48 volt circuit probably won't do anything. Connecting 48 volts and 12 volts together will destroy electronics and wiring. Be aware of what goes to what.
4. 12 volt lights, horns, and other devices are common and cheap and come in a wide variety of options.

Things you need to do...
1. You need to be able to isolate 12 volts from battery pack voltage. Typical DC-DC converters use a common ground wire input to output and the positive wires are isolated. you have a natural isolation built into the converter.
2. You need to turn off the 12 volt system or disconnect it's battery input or BATT+ wire. I do this via the key switch. It already is turning on battery voltage to the controllers internal DC-DC converter. I need the exact same thing for the external DC-DC converter. My key switch enables the controller and powers up the DC-DC converter at the same time. Be sure to use a key switch that can handle the current needs of the converter. They are inexpensive and readily available.
3. You need a power block so that you can provide battery power and 12 volts for whatever needs each one. I've shown pictures of samll terminal blocks I make for this purpose previously.
4. You need documentation of what is low voltage and what isn't. It doesn't need to be rocket science... something like this is just fine. Every connector and cable and module whatever it is has a diagram associated with it so that every wire has a home that can be found later.

Image

The Currie has a few terminal blocks in different places. They are all documented. I'm redoing alot of this right now to simplify things, but this was the original design and I can find any wire and where it goes since it's all on the piece of paper shown above.

Image
Image
Image

I start with documenting all the "stuff" at the handlebars first. Then I move to the motor controlller and then to the lights and horn. Now I have everything that is connecting to the handlebars, all the 12 volt system and the controller documented. All of that "stuff" needs to interconnect somehow. A battery bay terminal block is that point of interconnection. In all my EV's 99% of all small wires come together in a block like this. This terminal block gets laid out on paper before it ever gets put in the EV. Every position on the block is known before a single wire is screwed down. AFter that, it's a matter of taking what's on paper and doing it on the actual EV. If I can't follow my own documentation to actually do the wiring, then my documentation is confusing or incomplete. I learned this lesson the hard way on the blue scooter. I had to guess what went where and did a lot of rework becasue my documentation was wrong and what was in the scooter just didn't match up at all or was NOT documented in any way. You will be working on the electrical again...for some reason. Trust me and just document EVERYTHING and double check your work. Notice in the various pictures that the connectors are labeled and sometimes I use label tape too.

Image
Image
Image

IF I document everything up front, there is a very high chance that the 12 volt system and the battery powered system will be consistently separate from each other. Perfect! And that's the so called big complication of a dual voltage system. Essentially there's hardly none at all after you plan what you are going to do before you do it.

Here's a few pictures so you have some idea how I document things. The entire EV's electrical system is right there in a few diagrams.

Image
Image

Now that you know what to do, you too can build are a reliable dual voltage system that is easy to trouble shoot and modify as needed.
Image
Image
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Re: Everything you ever wanted to know so you can build an EV

Post by ElectricGod » Jul 17 2018 3:46pm

By now you've done some planning, thought about what voltage you want to run at, what gear ratio you need, how many lights you want on your EV, motors and motor controllers and so on.

What's next?

Now we are down to the practical building of the EV. This may sound backwards, but I like to start with the battery bay. I want it big as possible, sealed up as possible and accessible. Maybe your scooter already has a large battery bay and all you need is to seal it up. Do this now. Don't wait until it's full of water and dirt! Often times you have 2 frame rails like I did on the Currie, consider stripping off the factory battery box and making one out of wood or sheet metal that maximizes the space available. Honestly, in retrospect, I wish I had made the Currie battery box out of aluminum sheet. It would not have been difficult to cut the pieces and screw them together. I could have found someone with a sheet metal bender and done most of the box out of a single piece of aluminum. I could have made a better battery box than I did.

What else is a good starting place?

The motor needs to be mounted and probably the factory motor bracket is inadequate. Start stripping off the factory bits that are in the way of mounting your motor. Since you are starting more or less from scratch, remove all the extra stuff you don't need. Consider repainting the frame. I really wish I had! The Currie is red which is fine, but the paint is scratched up pretty badly in places. It would have been easy to repaint back when it was a bare frame.
ElectricGod...it's a joke...don't take things so seriously folks!

XB-502 Moped:
https://endless-sphere.com/forums/viewt ... 0#p1222730

Currie scooter:
https://endless-sphere.com/forums/viewt ... 7#p1227407

markz   100 GW

100 GW
Posts: 6137
Joined: Jan 09 2014 11:38pm
Location: Alberta Canada

Re: aligning your back wheel and checking if your wheels are worth it or not

Post by markz » Aug 08 2018 4:03pm

FYI Leafbike sells a 18" cast wheel with magnets for $85 you could buy as a spare, and buy a complete setup. I am seriously thinking about doing this because of my spoke breakage problems. So if my "professional" paid for laced wheel w/new rim w/ 12G spokes because the holes on the flanges are too big and cant use washers with 13/14G double butted then I will go cast wheel. I just have no clue what the real dimensions are for the outter edges of the rim. My feeling is its motorcycle sizing I bet. Cast is only good for casual riders that dont pop curbs at speed, so no need to worry about a divot on the end of the rim wall. Yes: additional weight for the cast wheel but no more spoke hassle. I would even bet that the 1500W motor would fit in there! There are discussions on es about cast wheels. So if anyone wants a MXUS 3000W V2 say in the next couple months and I start having more issues then who knows, could be up for sale in Used section.

Spare 18" cast with magnets - https://www.leafbike.com/products/e-bik ... t-976.html

18" cast wheels - https://www.leafbike.com/products/e-bik ... otor/c-21/

1500W - https://www.leafbike.com/products/e-bik ... -1112.html

ElectricGod wrote:
Jun 28 2018 12:21pm
I have an uber cheap cast wheel that is deformed in the rim area. The axle bearings are good, but the rim is really bad out of round. If you have anything like this, you will want a new wheel. If you think there is wobble, but not sure, you can spin the wheel, and rest a permanent marker firmly on the rear frame so its tip just grazes the side of the rim. The marker will leave a line where it grazes the rim. If the rim wobbles side to side, there will be spots where there is no marker on the rim. This is bad.

Ebuilt   10 mW

10 mW
Posts: 23
Joined: Jun 19 2018 11:27pm
Location: West coast usa

Re: Everything you ever wanted to know so you can build an EV

Post by Ebuilt » Aug 09 2018 3:21pm

Hey god, thanks for all this info. Ive ordered the stuff from ebay to integrate my switches and buttons into a 7 switch cluster like the one you had built and thouroughly enjoy the fact that you make all this possible.

Ebuilt   10 mW

10 mW
Posts: 23
Joined: Jun 19 2018 11:27pm
Location: West coast usa

Re: Everything you ever wanted to know so you can build an EV

Post by Ebuilt » Aug 13 2018 9:26am

God, can you please clarify a little bit more about how to bridge the kill switch with a 1k resistor so that I can stop sparking my battery everytime I reconnect it for whatever reason.

Are you just squishing the resistor end wires between the two nuts of the kill switch itself?

I have both on the way in the mail. Thank you.

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