So I have a pack made from SKP and after my last ride I noticed that p-group 12 will fluctuate resting voltage quiet heavily. Most the time the p group is right in line with the other groups voltage wise but it will sometimes drop by almost .2 for a few seconds before going back up to normal. Idk what the problem could be or how damaging it could be to a pack that’s only a year old.
Have you checked the connections for the balance lead? My guess is a loose connection at either the solder joint or the harness. Check both, unplug the wiring harness and make sure all of the dupont m/f look ok and then make sure the harness is firmly seated when plugging back in. If everything else is gravy and the reading keeps fluctuating you may have a bunk bms.
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What do u do with the balance wires that are underneath the pack though?
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That looks like possibly some welds have come loose mate 
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You can route them so that doesn’t happen. Have a look at some examples of other brick packs. @JoeyZ5 is amazing at this. He has a thread you can check out:
There are lots of other good examples on the forum and in this thread as well. Do your homework.
If this is your first buld, I’d also suggest you run each stage of your build by this thread. There’s no such thing as too much consideration for safety when using Liion.
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Ive been doing this. Can confirm.
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A 3D print to pre-dent the positive side would also be a plus. Nice approach.
@ISOgone4good ya this is also possible. If this is the case you’ll notice that group charging and discharging at a faster rate than the rest of the pack. Cycle the pack a couple of times and observe the uniformity of (dis)charge.
I’ve made a few packs before but all flat or flexi ones with copper bus bars. This is the first brick pack.
I had a look at his packs and still can’t see what he does with the P groups in the middle of the brick? I’m guessing a tab is attached to the negative at the bottom and a balance wire fed up through the middle to the top then the whole thing siliconed. ?
Yes, folded nickel tabs are used for the bottom connections and all the balance leads are routed either along the top or sides of the pack.
Not sure what you mean here but assuming you’re talking about securing and insulating the leads…
This is a good reference thread too. Lots of solid balance lead routing here.
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I’ll take a pic of mine later in the week. As it’s a 14s3p sole of the groups are in the centre of the pack so it’s not an option for have the balance wires out the side. They’ll have to come up through the middle of the pack.
lol 
nice build
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Why no bms? Or at least harness for balance charging?
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Daly dumb or flexiBMS lite would easily fit with moving.
Pretty scary not having charge protection. Get an unlucky bad cell, or some loose nickel and shit can get hairy.
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So it doesn’t seem like one group is charging faster than the others. It just drops about .173V for a second or two then returns to normal. It will do this while riding and charging.
I assume it’s a loose weld or something. I just don’t know how to go about breaking the pack down and trouble shooting p group 12
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It won’t if everything is hunky dory. Say you have loose nickel or a bad cell, that group will charge faster. The charger won’t stop till 50.4v, but one will be over charged and the rest under.
BMS will stop the charging b4 the bad group over charges.
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I think you are wildly mistaken.
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Yeah. It seems like one of the primary reasons they exist…?