Tuesday, May 8, 2007

My Favorite Grind

Here is a close up photo of the grind that I use on my drill bits. I'll be showing how to grind it soon. The picture below it is of the bit while spinning. It brings up an important issue. Every bit and every chuck have some degree of runout, they don't spin perfectly. When chucking up a bit, try spinning it at high speed and look at the point. If it moves erratically, try loosening the chuck and shifting the bit a quarter turn. When you have the bit in the optimum position, the runout in the bit and the runout in the chuck will cancel each other out almost completely. I made a mark on the chuck of my drill and every time that I use a new bit, I make a corresponding mark on the bit once it spins true, then when I go to use the bit, it is as simple as lining up the marks.


Jean-Francois Theoret said...

Impressive grind! I am curious as to how you give it its profile. I'll be waiting for your instructions!

Have a nice day. Thanks again for the wealth of information you convey.

Rooch said...

Peter - For us slat back (post and rung) chair makers - it is important to note the point is way too long, and might go through the leg we are drilling. Is it possible to have the same grind only having the point just barely past the tips of the outside cutters?

Peter Galbert said...

Changing the length of the point is no problem, the process is very flexible and can yield all sorts of accurate grinds.

Anonymous said...

This is awesome - I am going to try it on my Tormek!

Thanks Peter.

-Chris in Colorado