Drilling/Tapping 901 Flanges
 

I have a 930 CV joint setup and need to drill/tap (Timesert) the two holes on each 901 flange where the original roll pins were located. I'm using a drill press @ 300 rpm (lowest) with Cobalt drill bits, but it's barely able to cut the flanges. I found some related posts talking about carbide drill bits, but wanted to check here first.

Has anyone successfully drilled/tapped the 901 flanges?

Thanks!

Rioprelude

I have not done this to a 901 flange, but deal with machining hardened parts often at work. Carbide bits would be a better option. You are correct in using slow RPM's to drill. One problem you are facing is that the bit is only using the outer most part to drill since the hole is close to the size it neeeds to be to install the insert, which wears the flutes out in short order. It may take several bits to do it. Then the fun part will be getting the tap to work without sticking and snapping off even with all the cutting fluid you can pour on it. All you can do is go "slow and steady". :)

I ended up using a carbide tipped masonry bit (~$10) and was able to cut through with no issues (very quickly). The issue I'm having now is trying to tap it, as you mentioned. I'm thinking about finding a machine shop that is setup to thread hardened parts.