Bruce,
There is a very good chance you measured incorrectly or the drill was undersize.
Errr Harold, will you explain that a tiny bit.
I measure the shank of a, say .500", drill. Stick in the machine and drill a .450" diameter hole? In mild steel? 1 inch thick?
Cheers,
Bruce (bruceinbangkokatgmaildotcom)
Harold is quite right. Ive been sorting out boxes of drill bits..and the shank diameter is NOT always the same as the bit diameter.
Ive measured Good .500 bits and they tend to actually mic out at .495-.502
Quite a range..and a head scratcher when the hole is too small.
Gunner
"Lenin called them "useful idiots," those people living in liberal democracies who by giving moral and material support to a totalitarian ideology in effect were braiding the rope that would hang them. Why people who enjoyed freedom and prosperity worked passionately to destroy both is a fascinating question, one still with us today. Now the useful idiots can be found in the chorus of appeasement, reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary responses to another freedom-hating ideology, radical Islam"
Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno
Let the Record show that Gunner Asch on or about Sun, 05 Jul 2009 14:00:34 -0700 did write/type or cause to appear in rec.crafts.metalworking the following:
I learned about the difference between "normal' drill bits and TiN coated ones. Didn't make much of a difference, just that the TiN drills made a hole some .005 over tolerance. Fark!
pyotr
- pyotr filipivich We will drink no whiskey before its nine. It's eight fifty eight. Close enough!
Damn, my posts aren't showing up on my monitor, but the responses to them are. Bear with me.
As has been alluded, drills can drill a hole that is undersized from the designated (and measured) diameter of the drill. It happens by the drill creating a less than round hole, so the minor diameter is smaller in size than the drill measures at the tip. A like sized pin won't fit the hole.
For those that don't know, drills are not straight. They are ground with a minor taper towards the shank, which is almost always a few thou smaller in diameter than the drill tip. That's to insure that the drill doesn't bind in deep holes, assuming they cut size. They have been known to!
Twist drills are a miserable cutting tool at best-----although they do create holes! The web of a drill does not cut-----it displaces metal so the cutting lips can remove it. That's why split point drills do so well. They actually cut at the web.
Harold
replying to , Salinadow wrote: My work smith drill has a sticky feel
replying to , Salinadow wrote: My work smith drill has a sticky feel
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