Not sure if this should go to the Battery Builders thread since this is kinda a noob question, but when soldering 18650s together with nickel strips, should there be a few layers of nickel? Or an extra layer of copper (this seems ideal but I’m not sure how one would add say copper braid to nickel strips that have been spot welded)? From what I’ve read on this and the old forum, one layer of nickel isn’t sufficient for making packs.
you can go up to 8" on evolve hubs.
Where do you mean? The outside bearing only needs it if the head of the bolt touches the bearing shield
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Yeah good point. I was actually just thinking this.
One layer can be sufficient but it depends on a lot of things. Have you checked out the conductor current rating thread? I used that to decide what my pack needed
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OK, got it. The bearing shield spins freely so i think I’m OK
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Thanks! I didn’t know this existed.
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No problem, it’s super useful, I reference it all the time.
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The root cause seems to be no circlip, don’t forget those
To fix it, I would probably use a puller to remove the bearing, like this one,
then remove the entire can/rotor, don’t try to get the bearing back in there, because the can is likely crooked from the extreme magnetic force and you’ll find it extremely difficult to get it perfectly centered so the bearing fits back in there. Easier to remove the entire rotor and then reassemble it.
thanks. i was disassembling it. I removed the circlip.in order to do so. moved the can off got part way… and stuck. then going back it pushed the bearing out as you see.
Thanks. that’s where I was heading. 
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Make sure the shaft is free of bumps and dings and sand those off before you try to force the bearing off
Maybe use a skate bearing to check for clearance
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taps_forhead.gif
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Yeah, sounds like there was some tiny imperfection on the shaft that caused the bearing to seize up during the removal. The typical tolerances between a shaft and a bearing like that are on the order of a few ten-thousandths to a few thousandths (0.0002" to 0.002") of an inch, so it doesn’t take very much at all to cause a jam. I always take a file or stone or some fine emery cloth and go over shafts like that prior to (dis)assembly, just to knock off any burrs or high spots that might be present.
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Can overheating lead a p group in a 12s pack to overvoltage, while discharging?
I am trying to understand how a p group got to 4.6v while riding. I used it quite a bit over it’s limit on a very hot day. I assume it reached well into cutoff voltage temperatures since i only stopped when my board died. 1 day later it was down to 3.7v (other cells stayed at 3.4v).
Alternatively, how can i check if a bms is feeding the correct voltage through all of it’s balance leads?
I do not have access to it’s internals (it’s potted)
n00b alert:
what is the size of a standard esk8 axle nut… I need some… don’t have a board with me and I’m on my way to Ace-Hardware
TIA
8mm shaft… m8? With nylock end ofc
I’m pretty fuckin’ sure it’s not a metric nut
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google says “5⁄16 - 24 UNF”
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gracias amigo… fuck me… I coulda googled it… lazy ass k00k…