pic: Team 3647: Gearbox

[artdutra04]

Originally Posted by Mk.32

Wow I never thought you could do that. Might give it a try
Instead of using a 5/8 endmill would just a stock of Tool Steel work?
Is just getting a good hex on the tool just a lot of time and patience on the grinder with careful measuring?

Tool still would work just fine. When I did this a few years ago, I used an old end mill because it already had a flat spot to set screw against and because there was a box of end mills with chipped/broken flutes available.

Grinding out a good hex profile was fairly fast to get it close, then slow and careful to get it right. If you have an indexing head, then that would be even more accurate than using a piece of hex stock as a tool holder for grinding the hex profile into the end mill/tool steel. The surface grinder I had access to did not have the standard machine slots to mount an indexing head to, but rather had a smooth surface magnetic chuck, which is why I just used a piece of 1" or 1.5" steel hex stock as the tool holder.