Tuesday, July 28, 2009

Poor Man's Boring Bar

For an airgun project I'm working on I had to cut a 5/16" radius in a piece of steel.

I made a simple boring bar. There's a cross hole reamed to 3/16", a #10-32 setscrew in the center and a short bit made fron a broken end mill. I set the tool to cut the 5/16" radius. (3/8" bar diameter+1/8" tool sticking out of bar, for a circular sweep of 5/8")

I did a test piece in aluminum, feeding in then down, progressively.

Final cut.

Radius gage fits perfectly.

1 comment:

  1. Nick,

    I am getting ready to try something like this. Is the cutter a piece of steel that you ground and then heat treated?

    Rick Kernell