long through hole

[jonathan01]

I forgot that I had these. Are these good to use?

 

[brucer]

I forgot that I had these. Are these good to use? View attachment 54575View attachment 54576

personally I would not use carbide.

 

[Mid Day Machining]

personally I would not use carbide.

I would agree with that. If the carbide gets a little dull, it will work harden your material and you'll play hell getting through it.

 

[jonathan01]

OK, it was just a thought, being that the they seem like they have stiffer shanks.

 

[kd4gij]

What about drilling 1/2" hole and bore each end and put a bushing in.

 

[SE18]

great ideas here.

I'd like to add a pdf link to Harold Hoffman, who is a gunsmith. He drills long holes and stresses the right speed and lubricants. Hopefully this link works!

http://www.google.com/url?sa=t&rct=...=LweDaWiNbxmhpLFcE8Z-Rg&bvm=bv.47244034,d.dmQ