Official Erevo 1/8 scale center diff thread

[shaunjohnson]

Originally Posted by simplechamp

As previously posted I actually had my local machine shop tell me they couldn't even do it. Ended up spot annealing and using a pure carbide bit as suggested by mistercrash and it was a piece of cake. I'm kind of interested to see how it would be drilling an un-annealed cap, just to compare it and see how much the annealing helped. Also used a cobalt tap for the threads, but depending on what design you follow you might not need to tap at all.

if un-annealing means un-hardening then it was fine to drill with.
just heat up till red hot, then cool as slowly as possible for 24 hours (cement dust works a treat) and then drill with a standard drill bit.

edit: first LST diff in final stages now, i ended up using the traxxas center diff gear on the LST diff instead as that is what i had on hand. will fill with 100k oil then go try and kill it on 6s

shaun

[simplechamp]

Originally Posted by shaunjohnson

if un-annealing means un-hardening then it was fine to drill with.
just heat up till red hot, then cool as slowly as possible for 24 hours (cement dust works a treat) and then drill with a standard drill bit.

edit: first LST diff in final stages now, i ended up using the traxxas center diff gear on the LST diff instead as that is what i had on hand. will fill with 100k oil then go try and kill it on 6s

shaun

Annealing is softening the metal. I did spot annealing at the suggestion of some guys on a CNC forum. Yes, the metal drills very easily after annealing.

What I was saying is I would like to compare drilling the annealed metal to drilling the stock un-altered hardened metal, and see just how much the annealing actually helps.

I don't think you need to wait 24 hours and use the cement dust. Cement dust or not the metal will be cooled to ambient temp within 15-30 min. at most

[shaunjohnson]

i chose cement dust from personal experience, i have had a larger item kept red hot for hours on end by putting it in cement dust as it has good insulation capabilities.
shaun