Anthony Whitesell
09-14-2013, 10:24 PM
I'm in the process of finalizing the rebuild of my old delta drill press. I think it is coming out SWEET! I had a few industrial controls and electrical fittings that required holes. I have the 3 piece unibit set from Harbor Freight but it only went to 3/4". I needed 13/16, 7/8, and 1 1/16. I found an Irwin unibit that stepped from 1/2" to 1" in 1/16" steps. For the 1 1/16" hole, I used a carbide bit to grind it out the last 1/16". The Harbor Freight trio cut like a hot knife through butter. The single Irwin Unibit cost me 3x the Harbor Freight trio. I had to work at getting the Irwin bit to cut at all. I was cutting aluminum ~1/16" thick, and electrical PVC box ~1/8" thick. When I finished for the night, I tried cutting a piece of tin flashing and got pretty much the same result. Harbor Freight was a gem, the Irwin cut like junk. I'm assuming that Iriwin bit needs a bit of honing or flat out sharpening. Has anyone ever tried to touch up the edge on a unibit?