There’s an Amazon seller who has a good amount of shrink and the kweld north America guy sells shink tho he’s pricy and doesn’t put the measurements on the smaller ones.
Amazon: 200 specifically
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Thx boys. Much respect 
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Earliest any of the american vendors can get 200mm here is like 2 wks. 250mm is available locally. Can I get away w that size wrap? It shrinks by almost half no?
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It shrinks to 0.6 usually so 250mm becomes 150mm
Thx man. I’m gonna grab that shrink and see if it works
Made some good progress on the pack today. Did the main terminals and all the series connections. Pack gave me the proper voltage (37 and some change) as I had all the cells at nominal. Roughed in the bms and did some additional insulation. Had a bit of a scare as I forgot a very important precaution and was rushing a bit. Some sparks and a lesson learned- always cover connections you’re not working on 
Next up, wiring the bms. I’m likely gonna get that done tonight but not sure yet… Been working on the pack all damn wk and might just take 'er easy tonight w a cocktail and perhaps some of Canada’s finest concentrates. I’ve fuckin earned it 
Thx for all y’alls help and feedback so far. Would appreciate any comments on my work today as well 
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I’m looking for a 12s bms and I found supower bms and I’m wondering if anyone has bought from them before and how long shipping would take to the us
I have, it usually took 2 weeks or so. Might be longer right now, it’s basically the same as ordering from ali express
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Oh hai. Me again. This joint looks cold to me so I’m gonna fix it. Given that it’s between the two cells, I’m thinking that I can reflow it quickly using high heat and an aluminum sink touching the nickel beside the joint if I’m quick about it. Opinions/experience about reflowing so close to the cell? Tia
Edit: not sure if this post should go here or the noob thread… 
Should be fine, just be quick and use a lot of flux. Heat sink on the cell is a good idea, but dont get so caught up with that that you linger too long with the heat on. Also, mask off the other cell contacts next to to your work area to avoid a 
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Thx m8. Cheers
Yeah as long as your in and out it will be fine. Also try and use a 80w or more iron so you can do it quicker. But if not it’s still fine.
I’ve got a 72 watt that can go up to 490C and has been pretty solid so far so I’ll just crank that fucker up. Should be ok. Thx for the suggestion tho 
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That’s a sketchy place to solder. Right over the hot edge of that can.
If I have to do something like this, I like to try and sneak a bit of fishpaper under the hot spot. Good luck
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That’s not a bad idea… I honestly think I can get in quick enough to do it. The copper wire will also draw heat away from the cells.
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So I’m trying to get a feel for this kweld on my practice cells. with 0.2mm nickel.
Given my first feedback above that things looked hot. ( 60J) I started at 50J and went downward till I felt things weren’t holding very well or tearing nicely (40J) then tried to come back up. on the way up 45J things seemed decent but then 47J and 50J started to actually seem worse. till I got this last one that pulled off leaving indentations in the cell and barely pulling nickel.
I’m concerned about the apparent lack of consistency. so any advice or pointers to reading would be appreciated.
- battery voltage
- system temperature
- electrode cleanliness
- electrode pressure
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^^those, and also
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clean all your parts. Clean electrodes, clean nickel, clean cell. Light scotchbrite may be necessary to remove any stubborn surface crap.
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Also the electrode shape. If they get too dull, they don’t weld as well.
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I only got through a bit more than 50 test welds. I was going slow system wasn’t too hot. voltage hasn’t dropped much.
I noticed amps going up as I went. 1180 -> 1215A I think because I got more consistent and firmer with pressure.
I think everyhthign was clean except maybe the electrodes.
is 50 welds enough to corrode or misshape the electrodes. What are good electrode cleaning techniques?