Bubba's Build 5

[dontsendbubbamail]

I was trying to keep the weight low and save the triangle space for the water bottles. On hot summer days I need two bottles.

Ever considered a Camelbak Hydration pack Bubba...can move
all the motor and what not into the triangle then

KiM

I tried one for a while, but didn't like having something on my back. Bubba is just picky.

Bubba

 

[spinningmagnets]

Bubba, I'm not trying to change your water-bottle storage choices, but...just an idea....I tried making a water bottle holder that sits on top of the frames top-tube just behind the handlebar stem. I got a cheap wire mesh pencil-holder, and just used zip-ties as a test. I like it there, so I am working on a more professional-looking solution.

edit: in response to the pics below, thanks, Bubba!

I also like the Gatorade bottle that has a top which twists 90-degrees to allow the spout to pour. I find its easier to open with my teeth and one hand, rather than the common pop-out and pop-shut tips.

 

[dontsendbubbamail]

Bubba, I'm not trying to change your water-bottle storage choices, but...just an idea....I tried making a water bottle holder that sits on top of the frames top-tube just behind the handlebar stem. I got a cheap wire mesh pencil-holder, and just used zip-ties as a test. I like it there, so I am working on a more professional-looking solution.

I also like the Gatorade bottle that has a top which twists 90-degrees to allow the spout to pour. I find its easier to open with my teeth and one hand, rather than the common pop-out and pop-shut tips.

Here is a store bought solution to an alternate water bottle position. It allows them to be mounted on the handle bars or seat post.

Bubba

 

[dontsendbubbamail]

I may be Ok on my front tire to battery box clearance. My 7 speed cassette finally got here so I was able to go for a test ride. The tire never touched the battery box even though I tried to make it. Specs on the fork says it has 1.97 in (50 mm) of travel and I have about 2.5 inches of clearance between the tire and battery box. I suspect 50 mm is nominal and not max so I may still need to create a hard stop.

Bubba

 

[dontsendbubbamail]

Virgin cnc machine.

Bubba

 

[AussieJester]

Bubba has nice toyz :lol:

KiM

 

[recumpence]

Ahh, that mill looks familiar. Looks like Bubba is going to have fun converting it to CNC spindle drive.

I have roughly 3,000 hours run time on my Taig CNC. They keep on running! You will, obviously, need to adjust the ways occasionally. But, other than that, they just run.

I really need to get some CAD software and learn how to use it. I am still programming G-code.

Matt

 

[dontsendbubbamail]

Ahh, that mill looks familiar. Looks like Bubba is going to have fun converting it to CNC spindle drive.

I have roughly 3,000 hours run time on my Taig CNC. They keep on running! You will, obviously, need to adjust the ways occasionally. But, other than that, they just run.

I really need to get some CAD software and learn how to use it. I am still programming G-code.

Matt

What hold down system do you use?

I had been using Tubocad version 10 for many years and it works just fine for 2D. It didn't work on my new computer with Win 7. Searching the internet, I found Turbocad 14 for $10 from Purplus and when it arrived it ended up being version 15. Turbocad 17 is the latest version and costs $99. Any version can do 3D, but I think the interface sucks. The only difference I see between version 10 and 17 is just window dressing on the UI. Pair this up with a CAM application like SheetCam and you will never go back to doing it by hand. Just make sure the CAM application you choose has a tabing feature.

Bubba

 

[recumpence]

I made an elevated platform that I merely use spring clamps to hold the plate down to the table. Picture a kitchen table with one huge, thick leg under the center of the table, rather than 4 legs around the edges. All parts are clamped around the edge of the table with clamps. I use a 1/8 inch piece of Delrin under the plate I am machining for cutter cut-through clearance. Nearly all maching can be accomplished with this method, especially plate stock profile cutting, assuming the plate is clamped down strong enough to eliminate movement when cutting.

I am self-taught. There are probably better methods than this. However, I have never found one that is more universal than this method. Plus, I can run a test cut with .020" depth into the Delrin clearance pad to get a profile shape. This aids in material placement and minimizes material loss due to too much overlap. I can nest more parts per plate that way.

Matt

 

[dontsendbubbamail]

I made an elevated platform that I merely use spring clamps to hold the plate down to the table. Picture a kitchen table with one huge, thick leg under the center of the table, rather than 4 legs around the edges. All parts are clamped around the edge of the table with clamps. I use a 1/8 inch piece of Delrin under the plate I am machining for cutter cut-through clearance. Nearly all maching can be accomplished with this method, especially plate stock profile cutting, assuming the plate is clamped down strong enough to eliminate movement when cutting.

I am self-taught. There are probably better methods than this. However, I have never found one that is more universal than this method. Plus, I can run a test cut with .020" depth into the Delrin clearance pad to get a profile shape. This aids in material placement and minimizes material loss due to too much overlap. I can nest more parts per plate that way.

Matt

How about a picture of your table?

I am in that same self-taught boat. I have been using two layers of shirt cardboard to space the work off of the table and cutting .001 past the bottom. The problem is that the cardboard compresses and the work may not be parallel to the table. Using Delrin is a better solution, but I might see how some less expensive plastic like cutting board or pvc works. The cheaper plastics getting soft from the heat generated by machining might be an issue.

Bubba

 

[recumpence]

Good material is high density fiberboard. But, it absorbs lube, so you cannot reuse it often. Delrin, or high density plastic works well and lasts a long time. I have been using the same pieces for years.

I will see if I have any table pics for you.

Matt

 

[dontsendbubbamail]

Oops!!!!!!!! Bubba done gone and screwed up. I was trying to test a controller when I hooked it up with reverse polarity. There was a bright flash and my first two fingers and thumb turned black. At first I thought that was some serious damage, but It is mostly a first degree burns except for one place on the thumb where it is like I touched a hot soldering iron. Lucky all the black washed off. I should have taken a picture of my hand, but I was a bit preoccupied with first aid.

Bubba

 

[recumpence]

That is awesome!

I did the exact same thing!

Glad you are not seriously hurt.

Matt

 

[mud2005]

this is why I cringe every time I plug in a connector even when I'm "sure" it's right.

 

[spinningmagnets]

Glad to hear you're OK. I noticed in the pic that one blade is much worse than the other, could you tell me if its the positive or the negative?

 

[recumpence]

Glad to hear you're OK. I noticed in the pic that one blade is much worse than the other, could you tell me if its the positive or the negative?

That is the positive leg. However, the only reason that leg is so badly blown is because the negative leg was inserted first, then the positive leg arched badly while the negative leg had decent contact.

Matt

 

[spinningmagnets]

Would it matter if I put a fuse on the positive or the negative leads? Plan to add an on/off switch and a parallel pre-charge/resistor circuit so there wouldnt be any spark at the plugs...

 

[dontsendbubbamail]

Would it matter if I put a fuse on the positive or the negative leads? Plan to add an on/off switch and a parallel pre-charge/resistor circuit so there wouldnt be any spark at the plugs...

I have an 80 amp fuse on each of my 12s packs that are in parallel, so in theory that gives me 160 amps max. My fuses did not blow. There are slow blow and fast blow fuses. The ones I am using came from the auto store and I suspect that they are slow blow fuses. Slow blow fuses can take 2 or more seconds to blow. These fuses are less then optimal because they are rated for 32 V and I am running them in a 48 V system. It is possible that they will not be able to suppress the arc if they did blow. This means that current will keep flowing until enough of the fuse is burned away to create a gap big enough to stop the current.

I think that when you find a switch that can handle the current and voltage of you system it will be bigger than you would like and cost more than you would like. There is a solenoid out there that can handle 200 or so amps that might be a better solution than a switch alone, but it is still pricy.

Bubba

 

[recumpence]

I have a huge (2 inch square) on-off switch designed for the marine industry that is good for 1285 burst amps, 400 amps continuous.

It is big, though..........

Matt

 

[katou]

I have to say, why people avoid using contactors, switches, and fuses is still pretty confusing to me.

I'll work it out as necessary, but I notice that many builds have no "on" switch at all, they are live as soon as the battery is connected.

That seems kind of odd to me. Ideally I would want a nice key lockout switch for all of my builds. Are switches/contactors/solenoids hard to implement?

Katou

 

[dontsendbubbamail]

I have to say, why people avoid using contactors, switches, and fuses is still pretty confusing to me.

I'll work it out as necessary, but I notice that many builds have no "on" switch at all, they are live as soon as the battery is connected.

That seems kind of odd to me. Ideally I would want a nice key lockout switch for all of my builds. Are switches/contactors/solenoids hard to implement?

Katou

Just from a safety perspective, I think any system should have a fuse on the battery. This is just in case you have a serious fault. On RC ESC systems, blowing a fuse can also blow the ESC, so folks tend to leave them out. Another reason for RC ESC systems to exclude switches is that you want the wire length between the battery and the ESC to be as short as possible to keep ESC killing voltage spikes down.

If you are using an Infineon style controller, the wiring length between battery and controller doesn’t seem to matter as much as it does in the RC ESC system. On these systems you have a way of cutting off the power to the controller’s microprocessor while leaving the power connected to the fets. This allows you to turn off you system with a low voltage switch. There is no need for a large high current switch and you don’t have to unplug the batteries to charge if you include a connector for charging coming off your battery leads. Besides when one of these systems goes it is so fast and violent that you are not going to be able to turn the switch fast enough to save anything. If you don’t have fuses then just back away and let it burn.

Bubba

 

[Gordo]

I have to say, why people avoid using contactors, switches, and fuses is still pretty confusing to me.

I'll work it out as necessary, but I notice that many builds have no "on" switch at all, they are live as soon as the battery is connected.

That seems kind of odd to me. Ideally I would want a nice key lockout switch for all of my builds. Are switches/contactors/solenoids hard to implement?

Katou

When reading many of the posts I find people do include a "master" switch and/or a fuse. All of the commercial built scooters I have looked at have either a fuse, a relay or a breaker or all 3.

 

[dontsendbubbamail]

Build 5 is on the road. I went with a 12 fet controller because I cannot get a 6 fet to work for me. Don't know what I am doing wrong, but one day I will figure it out. My controller has the standard 60 amp Nec K3435 fets and traces have been beefed up with solder wick. It bogs down on the hills at the 30A current limit, so I will up the limit to 40 or 50 amps and see what happens. Top speed is 27ish mph.

Bubba

 

[Jeremy Harris]

Looks really nice, Bubba. I love all the CNC'd brackets, they really inspire me to get my arse off this chair and finish my own CNC machine.

What was the issue with the 6 FET controllers? I've had great luck with getting these to work well. I'd be more than happy to help out with advice, if I can.

Still, it's a really nice build as it is, should go well on 50A I should think.

Jeremy

 

[dbaker]

Beautiful job, Bubba What is the total weight?