Use Red Loctite for everything* imo
A lot for permanent stuff
A tiny lil drop for things you may need to disassemble in the future
*And ONLY 648 to adhere a motor pinion to the shaft on boardnamics gear drives
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Okay !
Thanks
I use 638 on all my shafts. Fight me
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I hear that’s good too, but I have no personal experience with it
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Pfft, what kind of fight is that 
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Seems its like most things in DIY - a lot down to individual preference / what is at hand
Looked through
but recommends 3 different types, guess the sealey one is not suitable so will have a look at 290 & 263
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I have a 12s4p battery made with 30q and charged with through a daly bms that is approaching 2 calendar years old but has been barely used. I estimate it was fully discharged about 3 times total over that time period because it was a battery for a build I took apart pretty quickly. I stored it at around 60% when I wasn’t using it. I built a new board out of spare parts recently and realized it won’t charge past 48.1 volts.
I am looking for general advice on what to do with this thing, must be a couple bad cells in this thing right? Worth it to seek someone out to try and repair it? I should definitely not use it anymore regardless?
Measure the voltage of all the p groups to get a better idea of what’s going on inside the pack. You can use a voltmeter on the balance leads.
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just make sure not to short any of them because they are very close to each other
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Anybody who’s fucked around with tool batteries got guesses as to what the resistance and c are doing? C maybe continuity? Ohms symbol is resistance so maybe a thermistor?
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Oh dude these things are so annoying
I couldn’t even figure out how to manually charge my ryobi ones, there’s a different voltage across the C, don’t know exactly how it works but there is some kind of check that happens before it’s allowed to charge. The BMS won’t even let the battery charge if you just hook up to pos and neg
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To avoid shorting adjacent pins as @frame mentioned, put your negative probe on a battery negative that’s far away from the balance lead and then only use the positive probe on the balance connector. Having two probes near each other is much easier to short stuff together if your hand slips, shorting neighbouring pins with one probe is definitely still possible but a lot harder because they’re somewhat guarded
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I’d guess NTC (thermistor) and communication with the onboard BMS. Many tool battery chargers won’t charge a battery unless they can talk to the onboard BMS and make sure everything is hunky-dory.
Depending on the tool brand, the onboard BMS may or may not be able to cut power/charging too, so just forcefeeding it often won’t work either - I know the Ryobi HP 2Ah batteries are that way since I’ve tried with them.
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Ok. So. If you were me and you wanted to chop/grind some ~11mm spheres of unknown metallic alloy into half spheres, how would you go about it?
@jack.luis @glyphiks
638 vs 648: in my experience they are equal as retaining compounds once cured, but 638 is significantly thicker in it’s liquid state. I find 638 easier to work with, though 648 probably has the benefit of seeping into cracks better.
Edit: specs say 648 is good for gaps up to .15mm and 638 is good for gaps up to .25mm. For us, this means 638 is objectively better for parts with not so tight tolerances(which should NOT be your motor shaft/pinion), and just a little easier to use imo.
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I’d epoxy or solder them onto a flat metal fixture or plate, and then grind away until they’re flat (watch temps, cool often). Then heat to melt the epoxy/solder to release the leftover halves.
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Does kerf matter? Do you need both halves, or is one half of each sphere sufficient? What tolerance do you need to keep?
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I would throw them away, get some bar stock of approximately the right size, chuck it in a drill and grind/file a hemisphere onto the end, then cut off the hemisphere. Repeat as needed.
Work holding with spheres is just fucking painful, and not worth the effort IMO unless they’re some whipshit unobtainium alloy crafted by nude greybearded virgins.
Or do something like what Frank said if you’re adamant about using the balls.
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I’ll have you know I held hands with several girls, so not quite.