|Forum topic by coloradoclimber||posted 12-28-2009 06:53 AM||6894 views||0 times favorited||7 replies|
12-28-2009 06:53 AM
I saw Jim’s post questioning how to sharpen a Forstner bit and not wanting to hijack his thread I’ll start a new topic.
I’m wiring up a new basement and needed to drill lots of 1/2, 9/16, and 5/8 holes in the studs and headers to pull romex through. So I pull out my big box set of spade bits, you know the ones, cheap for a full set, soft steel, start dull and stay dull til you throw them away. I’m happily, or rather unhappily, drilling away and thinking man, could these bits be any duller.
So I decided enough is enough, I pulled out an 8 inch mill file and took to it. I wont go into how to sharpen a spade bit, it’s pretty obvious. I held the bit against a stud to steady it and gave it a few strokes into the bevel, then ran the bit face flat on the file a few strokes, and wow what a difference. I mean duh, but I’ve never really thought of sharpening a spade bit before, use ‘em, abuse ‘em, throw ‘em away.
Anyhow once I got a sharp bit I was addicted. The cut was so much faster and cleaner, and easier on the drill. Problem was the soft steel of the bits dulled out again in half a dozen cuts or so. And once I’d starting drilling with a sharp bit I couldn’t stand using it dull. I was popping it out every 8-10 holes and giving the edge another lick. Fortunately it is fast and easy to re-touch the edge and I didn’t worry much about the cutting angle or maintaining the same angle, cheap bits and all.
Anyhow, if you use spade bits and you’ve never thought to touch up the edge it is fast and simple and really makes a difference.