What are some of the torque specs for the things we commonly do in first? I know how tight things should feel generally, but I would like to know the numbers for some of it to help with explaining to the kids.
For example, the bolts that mount a motor to a MK4i swerve module. Or the bolts that mount them to the frame.
Mostly 8-32. 10-32, or 1/4 into aluminum
Also, what are some of the good torque wrenches people use for such things?
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Main breaker studs - 1/4-28 - 50 in*lbf max per the cutsheet
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As my uncle would say, keep tightening until it gives, then back off a quarter turn 
I think a lot of things in FRC that may be torque dependent are handwaved away with the excuse of “Loctite”.
Battery lugs are a good one, maybe motor mount screws?
If I think I need a torque spec, it’s either going to be on the part’s documentation, or I do a Google for the materials and size.
And then I use the torque wrench to make sure I don’t go too far over and break off the bolt/stud.
I suggest having your kids twist off some bolt heads so they get a feel for the torque needed and can identify the “sinking feeling”
1/4-20 is the largest bolt where you can easily twist off the head with the standard length wrench.
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Going to help fix this soon… very soon.
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Torque values for different sizes and grades of fasteners are easily found on them internets.
NASA has a great paper on it. Here is the chart for steel English fasteners threaded into 1/4in thick 6061-T6 (very common in FRC):
Also common in FRC, here’s a chart for toque vs thread engagement for 10-32s:
If you’re using properly sized nuts or another situation where the bolt is the weak link, this chart is great. Here’s a snippet:
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I have seen some really bad connections on the battery post side of this equation too. There has been a bit of testing on this front, there are some papers floating around CD on it. But this is an excellent student teaching opportunity for several reasons ( loss of robot performance, mechanical and electrical problem, safety (could get hot), hidden connection)
One thing that I am interested in but do not have the resources to pull off rn is a white paper on cold flow of threads in Onyx under various torque/time/# of threads engaged parameters.
How do you manage to twist the head off before stripping the drive shape of the bolt? Unless you’re using hex heads and not allen/torx/etc?
Yes, when you are doing the “learn what it feels like” you want to use hex heads. Either put the bolt head in the vise and turn the nut, or use a hex head bolt. Its easier to feel things if you add in a spacer rather than just having a super-short bolt.
Button heads SHOULD booger up the socket before you twist off, but you are likely to damage the allen key doing it 
Hex head capscrews MAY twist off before stripping.
Torx is going to go farther…
A hex bolt WILL break the bolt first, as long as you either use a real wrench (box end for the win!) or set your “adjustable nut rounder” correctly
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