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Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Tue Sep 06, 2011 4:03 pm
by johnrobholmes
The mags are pretty tough, but you are right that once they get bent you are SOL. Many of the peds use 41 or 420 chain. Some of them are funny metric that is hard to get though.

You could easily use a Puch hub or wheel. They are pretty cheap and easy to come by. Do you care what the width of the hub is?

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Wed Sep 07, 2011 2:59 am
by amberwolf
As long as I can get at least two of the same one, I don't care, as I am building the swingarm from scratch anyway. :)

Wider is probably better, as far as that goes.

I'd like at least two because I want a spare for when I break the first one and need to get it going again in a hurry, when I only have time to swap a wheel and not fix the broken one. It almost certainly will happen at some point, so I'd rather be prepared than down for days or longer. ;)

I *would* like to get the largest diameter wheel I can, so I have more space between the axle and ground for tilting over on turns while still having cargo as far below the axle line as I can get it. My reasoning may be faulty, though, so point that out if so.

Size of wheel won't really matter for gearing, as I have at least two or three, even four places to change that at. :)

BTW, in googling around for Puch pics and stuff, I found this puch five star disc brake set up: ... brakes.htm
mike-thomas-5-star-disc-brakes-2.jpg (48.24 KiB) Viewed 2634 times

and this sprocket: ... rocket.htm
snowflake-rear-sprocket-2.jpg (34.54 KiB) Viewed 2634 times

and some other puch stuff at teh same place ... h=puch+hub
All way too expensive for me, but probably not bad for people that actually have money. :lol:

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Wed Sep 07, 2011 3:42 am
by gogo
Be aware that the Minarelli-motored mopeds combined the pedal input with the engine's and don't have a freewheel on the wheel hub. Any of the Puch or Motobecanes do have a fixed left motor sprocket along with a freewheel on the right for the separate pedal drive chain.

I have a Jawa that has a fixed motor sprocket on the right and a freewheel on the left that is driven from a pedal crank that runs though the swingarm pivot!

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Thu Sep 08, 2011 5:13 pm
by amberwolf
I still haven't been able to get back to this bike to build anything yet, with Bonnie being very sick the last several days. Easy to spend time at the computer since it's right here at the bed, where she is usually staying at (when we're not just outside sitting enjoying the daytime shade or the nighttime coolness, for her potty breaks). I think she's had a mini-stroke, as she is very weak and has problems with her left legs, balance, etc., and has trouble eating unless I put the food in her mouth, at which point she can chew/swallow ok. Had to switch to more liquidy foods to get enough fluids into here, though, and that started off the squirts, and she definitely isnt' doing as well now because of that.

She's such a tough girl it's hard to even tell if she's not ok with things, because she's always been the stoic independent type. Since the event, I've had to lift her front end with the walking harness, and walk along side her left side to let her lean on me as we shamble back and forth. Last couple days she can't really do that, though, and I've had to carry her, whcih she doesnt' usually like--she's tolerating it now, becuase she has to.

She is so persnickety that she will not even go potty or pukey in the house unless she has no choice at all--she pants and shifts around like a little kid holding it in to get my attention so we can go's endearing but frustrating becuase it's harder on her to have to transition from inside to outside (cool to hot to REALLY hot), especially since I've been running the room's window A/C unit a bit to keep her cooler to feel better and maybe help her recover a bit (if she ever does). If she'd just go where she is I could clean it up...but she doesnt' want to. She's still trying to be like she was, and isn't ready to go yet, whcih is both happy and sad. :(

I am still pondering the swingarm problem, but haven't been able to mock anythign up to figure stuff out with. It'd help if I could figure out what wheel I will end up using.

The wheel problem...I will probably have to just design the swingarm with bike wheels in mind so I can get it going, and adapt it later to whatever I can scrounge for MC or moped stuff, eventually.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 10, 2011 3:04 pm
by amberwolf
Bonnie died yesterday, so now it's just working six days a week (and dealing with the aftermath) that are keeping me from doing much with this. Got some other stuff to do (pack repair/testing) for someone else by hopefully Wed, then may be able to get back to this.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 10, 2011 7:01 pm
by Harold in CR
Sorry to hear about Bonnie. It's always tough to lose a good pet.

Now, YOU need to get some rest, before YOU drop. I just don't understand how you have gone this far, with injuries, clean-up and steady work, let alone care for all the dogs, sick or not.

Ease up just a little, Bud. :) :)

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 10, 2011 9:09 pm
by Rassy
My condolences on your loss of Bonnie. We are cat people and have lost several to old age, the previous one after 18 years. Time and other animals help you get over it. Take care.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sun Sep 11, 2011 3:49 am
by amberwolf
Totally OT for the thread, but I want to post this somewhere, and a new thread for it seems silly, since I have already used various threads of mine for way-OT life-stuff before.

I couldn't even really write anything about this yesterday, much less talk about it, without busting into tears and crying like a baby for hours. So this is kind of a (hopefully) catharsis and such, since yesterday all I could manage was the pictures I put up over in the Pets thread:

Bonnie died in the middle of the night sometime well after midnight, I dunno exactly when. I'd been dozing momentarily like usual the last several days, waking after a minute or less and seeing if she'd drink more water or syrup/etc mixture, or nibble more food, which she usually would. This time when I woke and picked up her muzzle, her tongue was lolling out but her eyes were open, but unseeing, and her head was so incredibly relaxed I knew she was gone.

I just held her for a while, hardly feeling anything, unable to decide what to do. I got a flashlight and checked her eyes, with zero pupil reaction, which just made it that much more certain. When I picked her up I found her sphincters had let go, too, another telltale. It was HORRIBLE to feel her totally relaxed body, with no struggle against me picking her up, because she always detested that and wanted to do it on her own no matter what, and her head just flopping backwards was nightmarish. I almost threw up right then and there, and I did a few minutes later.

I could't think, really, coudln't decide anything, but knew i couldn't just leave her laying somewhere the other dogs might get to, because i didn't know what they might do--probalby nothing, but I didn't want to fidn out. So I put her in the biggest black plastic bag I had, and wrapped it over her, and put her in my kennel trailer so I could latch it shut to keep them out, as I had to start getting ready to go to work in a couple of hours or so; it wasn't even close to getting light outside yet I think. Not totally sure. I was so very tired I laid back down but could not sleep; I kept wondering what I could ahve done differently, and I kept having the impulse to go check her to see if maybe really she was just asleep, and I was wrong, and she was going to suffocate in that bag. Knowing it's stupid didn't make me feel any different, and I coudln't stop thinking that. I actually had to go check several times, whcih just added to the nightmarish experience and horror of it.

Eventually, after not actually sleeping anymore than minutes-long dozes (at most), each woken with a nightmare, my alarm went off and I managed to get ready for work, but the dogs wouldn't go outside for potty break, they were all standing aroudn the kennel (and i guess had been most of teh times I had gone to check on her after wrapping her up in there). I had to just hope they could hold it all in till i was scheduled to get back around 2pm or so.

As it turned out, I left work after less than two hours, because a few minutes after I got there I was taking care of the small animals, and one of the hamsters in our little hospital room had died overnight of whatever was wrong with it, little feet in the air, tongue sticking out, and that was almost stunning--it made me feel cold in a way I didn't understand, but I took out one of the little black bags we have to put deceased animals/etc. in, and put the hamster in it, and as soon as i did, EVERYTHING just hit me all at once, and I almost fell down with the power of the reaction, and the pain, and although I don't remember doing it, I guess my cry was loud enough to get the manager's attention in the office a couple of rooms away, though he didn't come see what it was becuase he was doing store-opening stuff that has to get done quickly. Later when i got keys from him for some habitats he asked what was wrong and I told him and he was very sympathetic but i couldnt' talk because I was crying so much, so i just went to keep going at the animal care.

I kept going and trying to do what needed doing, caring for the animals and stuff, but by the time I was done I couldn't hardly stand anymore, and there was zero chance I could help customers or run a register, so I gave him the keys back, told him all the animals were done, and that i couldn't do any more, punched out and kinda collapsed in a chair in the back room of the store, and kept crying for what must've been at least an hour. At some point I actually fell asleep for a few minutes, because I was still so exhausted from virtually zero sleep the last week of taking care of Bonnie. When I woke up, I was still on the edge of tears at every moment, and I rode home, with a few stops for emotionally overpowering moments along the way.

When I finally got home, the dogs were all happy to see me, and that helped, but I was still so exhausted and distraught that all I could really do was sit down, and I fell asleep again for a few moments over and over again, unable to even get up out of the chair for a while. Evnetually I got up and let them all out, and went with them to just be outside, where it was mostly cloudy and very breezy, and there was thunder now and then, but no rain yet.

I'd guess it was midday by then, from the sun, but I hadn't looked at a clock since punching out from work and didn't end up looking at one again until several hours later, at least. I knew I needed to do something with Bonnie, and I did not want to have her "disposed of", and I think cremation and keeping them around is pretty creepy, so I decided to return her to the earth, as I'd done with many dogs over the years especially when I lived in farm coutnry in Texas as a kid.

I picked one of her favorite spots to lay in the shade while waiting for Mom to come home, where she could see the end of the carport and most of the road, over by the northeast corner of the house. It already had a depression there from where she and other dogs had dug cool-pits to lay in, over the years. I deepened that a lot, and laid her in there facing the way she'd do when she was waiting. It just felt right. I also couldn't bring myself to clean and put away the last bowl she was using, so I put that in there with her still full. I know it's stupid, and wont' do anything but get bugs in there faster, but it felt right to do it, and wrong not to.

Since she was also Mom's dog, I wanted to put something Mom loved with her, that would last, and be visible, a reminder, a memorial without words, that even if no one else could understand, I would. So I picked the smallest Lantana bush, of which she'd planted many around the yards front and back, and dug out as much of it's root system as I could. If it had been a normal day I would've passed out from the heat doing this becuase I was not paying attention to anything including time, and hadn't even drank anything since getting up that morning. Actually probalby not since well before midnight the previous night; i can't remmeber for sure. But since it was cloudy and windy it was only about 90F, maybe less, lots less with the windchill factor. Felt like 70F.

I planted the lantana on top of her, and covered it all over, putting all the clumps of dirt with grass in them on the top layer so it'd grow back quicker. then watered it thoroughly, thinking all the while that if I was wrong she'd be drowning right now, whcih was really stupid (and I knew it then) because if she wasn't dead before she would've been after being in that bag for hours, and she was definitely gone when I put her in there. But I still could not help feeling it was all a horrible mistake. I *still* feel like that.

I still can't help wondering if I had stayed home from work and continously nursed her if she might've made it, or if I had been able to borrow money (that I would never be able to repay, most likely) for a vet, or this, or that, or this, or that, and it just keeps going thru my head. It's stupid, and I know it, and I still cant' help it.

This is a lot harder than all of the others I've lost except for Lady. I find myself having nightmares in which I've buried her but she turned out to only be sleeping, but when I figure that out, it's too late and I can't get her out. Or others where the rest of the dogs are suddenly just laying there with their tongues lolling out, eyes still open, just like Bonnie. Sometimes they are still alive, but can't move, and don't respond to me calling them.

And practically everything at work is reminding me of I tear-up at all sorts of things, trying not to start crying again because I can't help anyone that way, and if I can't help I can't work, and I can't afford to not work. Missing any hours at all is simply impossible, and I wont' ahve any PTO available till later this month. The managers understand perfectly how I feel; pets are children to most of them, too--but it's still a business and someone that's unable to do a job can't just stand around and get paid anyway, of course.

And I typically use my dogs as examples in discussing things to help customers figure out what they need, and Bonnie has been a frequent example in a number of areas, because many people know border collies well enough to relate. I keep starting to use her as an example and then I realize I'm using the wrong tense, and I can barely continue; I'm sure it's obvious something's wrong becuase some customers get wierd looks on their face that I don't know what they mean, but none have said anything so far.

I want to curl up in a ball and forget the universe, but life doesn't work taht way. If I did not have th other dogs, I might take that option, but no one else will care for them if I don't, so, it's not an option.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sun Sep 11, 2011 12:21 pm
by Pure
So very sorry man. I totally know how you feel. I love the bush idea, at least it's a living grave marker and will ensure she isn't disturbed for a very long time.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sun Sep 11, 2011 4:16 pm
by Solcar
I'm very sorry about your loss. I wish everyone were as thoughtful as you are.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Sep 12, 2011 7:48 am
by Whiplash
Awe man, I am so sorry, I know exactly what you are going through. I am sure you remember when my buddy had to go, and I still think about him all the time and its really hard not to cry.... it gets better, just remember, now they are not suffering.... again, sorry for your loss.....

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Sep 12, 2011 6:44 pm
by amberwolf
Well, the good news is I finally get a week's vacation starting this coming Sunday. I'd like to sleep thru the whole thing, but I doubt I'll get that chance. :lol:

Maybe I'll get something done on this bike in that time. Also gotta fix that Volgood pack:
whcih I have had to put off from lack of testing time. Now I've gotta go and set up the Sorenson to charge a low cell-group in it, then test it some more after I get more sleep than the nap I almost took while riding home from work today, which left me with enough adrenaline in my veins to keep me from even thinking of dozing for the last couple of hours so far.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 17, 2011 12:58 am
by amberwolf
I was going to try fixing up some of the welds, and finally welding the tabs for the coilover shock onto the frame (even though I may not use it later), and then cleanup all of them with teh grinder and flapdisk, but the welder is a complete POS and I simply CANNOT get the feed mechanism to reliably feed the wire. I've started another thread here:
about maybe getting ideas on how to fix that without buying another welder (or other parts) that I simply cant' afford.

Anyhow, until I fix the welder I cant' do much else with this bike except try to work out the swingarm stuff. I REALLY want to work on this bike during next week's vacation, though.

So all I did last few days here and there as I had time in daylight was to cut off that "block" of tubing just behind the front "seattube" that's going to be the steering pivot, and flapdisk/grind all the welds I could.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Sep 19, 2011 2:23 am
by amberwolf
I posted this in another thread about motor efficiency, but since the test I want to do will be done on this bike, here it is in this thread:

Regarding a statement by another that hubmotors are the most efficient motor to use, compared to running an RC motor thru the gears:

I would actually say "it depends", because if you use a hub motor and ride in stop-and-go traffic with few stretches where you can actually get up to any appreciable speed, but still must have it setup so that WOT gives you high torque for quick startups, as well as high speeds for the few stretches you do get to speed, it may not be as efficient overall as using a motor that runs thru the gears to be able to keep the motor closer to it's higher RPMs where it's not using as much current to produce the power output needed at various speeds.

If you do not need to worry about those stop-and-go conditions, and only compare them over long stretches at higher speeds, it is quite possible a hubmotor would be more efficient than a thru-the-gears setup.

But under stop-and-go conditions, it'll probably depend greatly on how long you can sustain higher speeds, and how often you must stop-and-go with startups of high-torque and power usage, for whether the hub would be more efficient or not.

I hope to be able to test this on my new bike build, by running my 9C 2807 first as a front hub on my commuter route for a while, and then running it as the frame-mounted motor driving a NuVinci hub that automatically adjusts ratios for best motor efficiency based on current usage and speed, on the same route for the same number of trips.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Sep 19, 2011 8:38 pm
by amberwolf
Progress on the swingarm. I decided I'll just build the swingarm itself, and design the pivot point at the same time, and then worry about how I will mount teh shock after that. Probably a dumb way to go about it, but at least this way I will be *doing* something, and I might be inspired along the way on how to do the rest of it. :)

I measured out enough swingarm length to go significantly beyond the dropouts, in case I decide to do a shock *behind* the rear wheel, going straight up to a lever arm that's part of the frame. Not likely, but at least it'll be there. If not, I'll just cut that off, when I start actually makeing the dropouts.
DSC04860.JPG (56.87 KiB) Viewed 2974 times

I may make them at the end of the swingarm, or I may make them *below* it, but probably for simplicity of chainline they'll be at the end of the arm, as shown in the drawn-on stuff on the rectangular tubing.
DSC04862.JPG (53.01 KiB) Viewed 2974 times

This will be a 90-degree rectangular swingarm frame, so that it is the same width all teh way from front to back. The two sides will be joined just forward of where the tire should end on a 26" wheel, even though I plan on a 24", so I have the option of the former if I need it.

The pivot itself I am considering various options, but since it needs to A) be buildable from what I have and B) have two rotating things inside it, one nested inside the other, the best I've thought of so far is using a steel rod (possibly two lengths of axle) that actually fixes to the bike frame's pivot point. Riding on that will be standard bearings from a scooter wheel, which are the typical "sealed" cartridge type.

Option A) Riding on that will be a tube constructed from tubing the size of the typical square-taper BB, that will have welded to it's ends some threaded bits for freewheels to mount to. The left end will probably be the open-threaded BB cup with lockring, so that I can lock the left side of the freewheel from unthreading itself in use. The rigth end just needs to be threaded.

Option B) riding on the rod/bearings will be a tube that has sprockets welded over it's ends.

Outside of either A or B would be the bearings and races and BB from the old one-piece cranks, as those are all just large enough diameter to clear all this stuff, IIRC. (I hae to actually dig one out to measure and be sure). The inner races would be welded to the tube from A or B above. The BB tube itself would be welded to the swingarm as it's pivot. Everything mounts into that, then is bolted to the "dropouts" on the rear end of the bike frame itself, and clamped in place.

I am having troulbe workign the mouse well enough to draw it up in Paint, so that will ahve to wait till alter.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 24, 2011 4:23 am
by amberwolf
Still letting the ideas stew in the back of my head about the swingarm and pivot. In the meantime, I kept digging for all my bits and bobs that might be usable for that pivot, including a bunch of old BB parts I thought I knew where they were (but didn't), and ended up finding all the right stuff at the same time for some of the battery things I meant to do a long time back.

First up was the 48V 1.5A current-limited linear power supplies Bigmoose had sent me (along with several other nifty things), which I had intended to turn into maintenance chargers for my old SLA stacks that don't get used much now, except to power bench experiments, and to occasionally run a UPS during power outages (very rare) or for portable AC power (slightly less rare). (portable being relative, in that the SLA and rackmountable UPS weigh close to 100lbs to run for an hour or so depending on load).
DSC04887psuonly.JPG (57.1 KiB) Viewed 2845 times

All I had to do was adjust their voltage pots to about 54V, whcih is pretty much the max it will go to, so it will charge 4 series SLA to nearly full (13.5V each). The current limit I left alone, though I did not check how much current was drawn on the first batch I set up, as it didn't occur to me till later once it was close to charged, and it's only drawing 300mA now.
DSC04887.JPG (73.62 KiB) Viewed 2845 times

I have a second set of four 17Ah SLA to put the other one on, after they are closer to equalized by charging up the lower-voltage pair of them (that I used last night to power the Venom to charge the NiMH) to match what the other is at. It's too much of a difference to just hook them all in parallel and let them self-equalize that way (over a volt), cuz it'd probably smoke the small wires I have for that, and possibly cause the electrolyte gel to boil, which is bad.

Once they equalize, I'll hook them up in series again, then the set to the other PSU and make sure to note the current at the beginning.

I also got the BIG Sorenson out, hooked it up, and started charging up the much larger 31Ah SLA. I'd already been trickle-charging one of the three on my little Sorenson, which only does 750mA max, for over a day; it'd already gone down to about 200mA load at this point, so I left it on there to finish, and put the other two on the 55-55 unit, at a 6A current limit, and 14.1V (paralleling the two SLA).
DSC04888.JPG (44.11 KiB) Viewed 2845 times

It dropped from 6A to 2.5A within minutes, and was down to 2.3A by the time I was taking pictures an hour or so later. Voltage went up from 13.1V to 14.1V in that time. Not sure how discharged they really are, but they would easily hold 12.5V or so with my 50W halogen on there, before hooking them up to the charger.

Now for the project I have wanted to get back to for AGES, because every time I think I have all the stuff for it, I get some emergency or illness or injury or all three that keeps me away from it, or I misplace some of the stuff while taking care of one of those things, and then when I have time I can't find them. :(

Anyway, I finally found all the stuff (except the v2.6 Fechter/Goodrum BMS parts :roll:) to build up the Thundersky 32V 60Ah pack. I'd bought the cells from Mechanix some time ago, (maybe a year? I forget now) with payments over several months (by skimping on everything else, back when I could "afford" to do that) and started collecting hardware to bolt them together and such, and make a balancing BMS, etc. The majority of the BMS parts were donated (the rest I had here as salvage with some old/unused parts), as was eventually the bolts and washers for connecting the cells together. I already had braid to make jumpers, and crimp-on lugs, and at one point earlier this year had managed to get all those parts in the same place in the bike parts room, before the city-ordered cleanup. After that, stuff got moved and so now I can't find the BMS stuff.
DSC04889.JPG (49.74 KiB) Viewed 2845 times

But I have the rest, so I took an hour or so and made up all the jumpers, bolted them betwee the cells, and found an Anderson SB50 already made up that I used to use on CrazyBike2's SLA pack, before I went to the NiMH and then the Vpower LiFePO4.

The jumpers are made of the tinned copper braid from old 75-ohm RF cable, with the core and the outer jacket removed. This makes them very flexible, so vibration should not break them.
DSC04893.JPG (36.09 KiB) Viewed 2845 times

They are simply crimped (no soldering) very solidly into the lugs, although these pics are probably too blurry to really see that.
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DSC04892.JPG (42.19 KiB) Viewed 2845 times

I have a little "kit" of pre-cut heatshrink tubing that a friend gave me after it experienced a bit too much of our outdoor weather, and most of the pieces have already partly shrunk from the heat. So while not unusable, some pieces can't be fully used, or can't be slid easily over the things they're meant to fit. I just picked a few of the least usable large diameter ones, and used them as sleeves over the jumpers, not shrinking them down, just leaving them loose (sicne they are too large to conform to the lugs or jumper braid anyway).

It's still not strapped into a pack form yet, because it will be made into two 5-cell boxes that can bolt to the cargo rails on this bike, but it is otherwise ready to test and use and charge as a pack.
DSC04894.JPG (48.73 KiB) Viewed 2845 times

I still wish I had a few more of these cells, as 32V is too low for a few of the things I'd like to use it for (like pretty much all my hubmotor wheel projects), though it should work fine for things that go thru the gears, as I can just step up the ratios if it's not fast enough (though this will increase current draw, these cells should be able to take that, up to at least 60A continuous, with easy bursts of 120A or more).

For instance, on CrazyBike2, it isn't even enough to be above LVC for the 12FET on there, so I can't engage the motor to do a quick test, whcih I was hoping to do. It's only 32.9V, with all cells being at about 3.29V, plus or minus a hundredth. Ignore the mileage, as taht is from testing RTLSHIP's repaired Volgood pack. It *is* enough to turn on the laptop adapter that boosts the pack voltage to run the CFL taillight, so that part works, but nothing else.
DSC04895.JPG (40.91 KiB) Viewed 2845 times

Anyway, for this bike, they may well do fine, as a secondary or long-range pack. Have to wait and see, once I get the bike itself finished.

Also, I finally ran across the two things I meant to use to pack the Vpower pack halves in, but they are just a bit too small in all dimensions for that. :( Sharpie on top of one for scale.
DSC04897.JPG (35.51 KiB) Viewed 2845 times

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 24, 2011 2:55 pm
by amberwolf
The 31Ah SLA charged up to 13.5V, with only a 200mA current still going, so I disconnected them to test the TS pack. (I'll stick them back on after it's done).

I am still not totally clear on the TS charging voltage, because some people say that TS uses a different chemistry than just plain LiFePO4 and so uses a higher charging voltage of 4.2V, and some people say that's a mistake in the spec sheet and means that's the absolute max you can ever put them to, and/or it's a "priming" charge used *only* for the very first charge cycle, and after that you use the usual 3.65V LiFePO4 charge voltage. :?

So for now I'll go with that 3.65V charge voltage, and so I set the DCS55-55 to 36.5V (10 cells) and rolled the current limit down to 1A.

I hooked up the Watts Up from AussieJester in between the DCS and the pack, to monitor capacity put back in and such, and started the charge. No problems at 1A, so I turned it up slowly until at 30A (0.5C), whcih the cells should be able to charge at without problems. So far, that's true.
DSC04898.JPG (31.28 KiB) Viewed 2833 times

The supply wires (8 gauge) get noticeably warm (body temperature?) at this current, though the SB50 andersons do not. My cell interconnects also get warm, about the same as the 8g wire. The 10g I have on the WU is definitely warmer than body temp, but not in any danger. The WU gets a little warm, too, so I set it on top of the fan intake holes on the DCS55-55. The cells so far haven't gotten warm, but there is a lot of mass to heat up so I might not notice till later, even after charging.

The interconnects drop about 0.03V across them, from cell to cell, which is a lot more than I expected. That's about 10mV/A. I measured across the crimps, and most of them read a flickering 0.01V, so I guess most of the drop is across the braid while the rest is on the crimps. Disappointing, but it is what it is.

The DCS55-55 actually gets a little warm itself, but given that it's doing 1KW of charging at this point, it's not surprising. ;)
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Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sat Sep 24, 2011 3:30 pm
by amberwolf
So less than half an hour later, it was "full", with only half an amp being drawn, at 36.53V.
33.69Vm (start of charge)

Of course, the cells are not quite in balance:
(Most negative at top, most positive at bottom, no load voltage on left, ~2A load with 12V 50W halogen across the cell on right)

3.74 3.68
3.60 3.54
3.69 3.50
3.38 3.30
3.35 3.17
3.53 3.45
3.42 3.36
3.51 3.34
4.12 3.91
3.51 3.39

I used the halogen to discharge the highest three cells down to 3.65V when measured without the load, which took about 7 minutes for the highest and about 1 minute for the other two.

Now I am using the DCS55-55 at 3.65V and the same 30A limit to bring each of the other cells up separately. The first one (next to most negative, call it cell 2) is only taking about 400mA (started at about 600mA), don't know how long it will take to finish. Then will have to do this for the other six "low" cells.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Sep 26, 2011 4:48 am
by amberwolf
I brougth each cell up until it took 0A, then moved ot the next cell.

Unfortuantely I blew up the WattsUp somehow, when I accidentally clipped both leads to the same cell interconnect jumper, one at each end of it, instead of to each terminal on a cell. :roll: I'll have to take a look at it later, but basically I put 3.65V with a current limit of 30A, thru the WU, and into a dead short. :( So whatever that might do to the WU regulator or whatever, BOOM.

FWIW, the WU barely works at that voltage, so it was already forced to be on it's ragged lower edge of voltage, then to shove that much current thru it for the several seconds it took me to figure out I'd screwed up was probably not happy.

So I don't have any other data from the charging, as I didn't want to risk screwing up again with TWM and toasting that, too.

All I can really say is that most of the cells dropped to 2A or less nearly instantly, and took less than 20 minutes to drop to 0A. A couple took nearly an hour, steadily dropping from just over 2.5A down to 2A in the first half of that, then thru the rest of it down to 0A.

I let evertyhing sit overnight, and most of the cells i'd doen this charging to had dropped down to 3.55-3.6V, one stayed up where it was. The other two cells that were laready over 3.65V that I didn't have to charge (and acutally had to discharge some) are still where they were last at.

Today before work, I put it back on teh Sorenson, and checked the voltage on the cells, but it was going DOWN extremely slowly, and I couldn't figure out why for almost two minutes. I also noted that the current was 1.0A exactly, which seemed kinda wierd for reasons I couldn't quite grasp.

That's because I'm a moron. :roll:

I had not yet changed the DCS55-55 output voltage from 3.65V up to 36.5V. :( So whatever protection the Sorenson has in it was shunting 1A of current (couldn't've been much more, as the wires stayed room temperature, even the thin ones), and slowly draining the pack.

I immediately unplugged the pack from the Sorenson and upped the voltage, once I realized my stupidity, and fortunately nothing was hurt.

Reconencting it started charging at about 13A, dropping down to 10A in a few minutes, and slowly dropping over the next 10-15 minutes to zero. Then rechecking all cells found them mostly at 3.60-3.70V, with the one high cell back up to 3.81V, dropping as I watched down to 3.75V. So they're pretty close to balanced.

Unfortunately i totally forgot to do the part I was trying to do before, whcih was to check the cells during high-current charge, to see if any went up a lot mroe than others, proportionally, which would indicate a higher internal resistance and potentially a problem.

For my next trick, I'll unhook the series connection and then paralelle all the cells, to get it to really teh same SOC (by voltae, anyway).

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Sun Oct 02, 2011 7:43 am
by amberwolf
In the several days since the post above, I've not had the chance to get back to the pack, so it's been just sitting, and the cells have all equalized (still in series) to 3.5x volts, no more than a handful of hundredths of a volt difference. No need to do the paralleling, I guess.

Oh, and the WU apparently isn't blown up, as I was going to try working on it to find out what was wrong, and it seems to work fine. Dunno why it wouldn't before. :?

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Mon Oct 03, 2011 3:22 am
by amberwolf
Another solution to a problem was staring me in the face, but I couldn't see it until I saw one of HAL9000's old builds:
where he put the pivot point on the outside of the main frame, rather than inside.

If I do that, I can easily make a single-level-bearing setup, where it has bearings for the pivot on the outside ends of the frame/pivot axle, and bearings for the jackshaft/powertransfer from in-frame chainline to swingarm chainline on the inside section of the pivot axle, which itself would be securely bolted to the main frame.

Now I just have to locate a shaft long enough for this; I think I have at least one besides the one Thud made for me.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Wed Oct 05, 2011 11:30 pm
by amberwolf
Here's about what the proposed drivetrain would be like:
drivetrain 2 (100511).PNG
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Blue is the main bike frame, dark gray is the swingarm frame, black wheel at rear.
Green is the hubmotor-in-frame, light gray is the NuVinci, black box is NV control unit.
Orange is pedal chainline, red is motor chainline, magenta is combined to wheel.

NV becomes both jackshaft, transmission, and pivot point for swingarm. Pedal and motor chains go into NV input, combined output driven on large chainring bolted to righthand spoke flange. (if a disc-brake-mount front bike hub I have can be made to work on the rear, I can use that to drive from the left side instead, using the disc mounts on NV and rear hub to bolt sprockets to).

To attach NV into both swingarm and bike frame, it is first installed into the bearing holes on the swingarm, loosely.

Then that partial assembly is placed onto the bike frame, inserting the axle into the "dropouts" of the bike frame.

Chain to pedals is tensioned via position in dropouts, and NV nuts are tightened down to secure it to the frame, and clamps on frame are secured across rear of dropout slots to guarantee it cannot come out of them and to provide clamp force as torque plates.

Bearings for swingarm are installed over (around) nuts on NV axle, pressed into swingarm pivot holes.

Wheel is inserted into rear dropouts with eye bolt heads on axle inside stays, with chain from NV looped over it's sprocket. Tension chain by pulling wheel rearwards in drpout slots by tightening nuts on rear of eye bolts. (ensuring it can't slip forward or be pulled by chain).

If room on NV axle permits, nuts and large fender washers are added to prevent any sideways movement of swingarm, but it is unlikely it could move anyway, even if room does not permit.

Motor chain is then tensioned by moving motor in it's mounting slots, and then locking down it's axle nuts and the clamps on the mount slots/torque plates.

This should simplify the drivetrain enormously from what I had been thinking of before, and the only change I must make to the existing frame is spreading the pretty narrow pivot dropouts so the NV will fit.

The one issue I run into with any of this is that I wont' have a freewheel on the motor, so if I have to only pedal it home, no motor, it'll be some extra drag there. I could of course just ensure I have my chainbreaker with me, and take the motor chain off in that event.

Also, some pics of my latest find, at Stardust building supplies where they resell salvaged building supplies removed from all sorts of places.
DSC04977full.JPG (53.28 KiB) Viewed 3175 times

It's a bunch of pressure hoses from various things, with stainless steel braided jackets. The two on the left (above) or top (below) also have a clear plastic over the jacket, the others are just the metal.
DSC04978.JPG (95.67 KiB) Viewed 3175 times

The plan is to remove the connector ends, and also the tubing from the center, and use the sheathing to cover the wires on the bike both for protection and for looks. (borrowing a bit from AussieJester's build).

I also got two 12V 11W plastic-cased tracklight assemblies, which could be used as headlights; they have a decent spot on them but not really good enough for as dim as they are. But they may make good reflectors for LEDs once I get some bright enough to use in there.

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Thu Oct 06, 2011 2:02 am
by amberwolf
Laid out the parts and took some pics; so it might look like this:
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DSC04981.JPG (47.05 KiB) Viewed 3168 times

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Thu Oct 06, 2011 2:57 am
by LI-ghtcycle
Looking good there AW! :D

Love the idea of using the braided metal hose covers for wiring conduit!

Re: Full-Suspension Semi Recumbent Cargo Bike - NuVinci MidD

PostPosted: Thu Oct 06, 2011 4:02 am
by amberwolf
So did I when I saw AussieJester using I borrowed the idea now that I found these things. :) Just need stainless steel zip ties to hold them down with. :lol:

I'd actually gone there with a friend who was looking for a small subpanel box and some other stuff, and what I had in mind was finding a stainless steel shelf or sink or *something* that was 3/16" or thicker, with a flat area somewhere on it that was at least 12-16" in diameter, so I could cut out a circle from that for a brake disc to stick on CrazyBike2's hubmotor cover bolt circle (there's no other way to fit one on any of the forks I have, and stll clear the calipers to the covers).

No luck on the steel, though I saw an aluminum skillet at a thrift store that was at least 16" flat on the bottom, and about 1/8" thick or more. If it had been stainless I'd've bought it, but aluminum probably wouldn't do what I want. (and if it would, I already have some things from rackmount stuff that would work).

I've been considering trying a disc just out of regular plate steel, as I have some 1/8" (maybe a bit more) stuff that used to be the base of a retail info stand. But I think it is probably too soft, and I'm not sure how it will work for braking. If I don't find anythign else soon, I will probably try it anyway, just as a test, since I'll still have my rim brakes and regen.