[AT] Drill Problem

[CBear81438 at aol.com]

In a message dated 12/17/2004 8:35:07 PM Central Standard Time,  
rasmith4 at juno.com writes:

I need  to drill a few more 3/8 holes in my cow stanchions.  I tried using my 
 normal drills but they quickly became very dull.  I suspect that the  
stachions are "hardened" steel.

Does any one know how do do this or  what kind of drill bit to use?



Low carbon steel subjected to a nitrate environment for a  long period  of 
time will become "nitrided", a form of hardening.  I run into this  problem 
repairing stock trailers that we get at farm auctions...   A  good high speed 
steel (read american made) bit willususally drill thru it.   However, the titanium 
nitride bits, the TBN or Gold ones will help.   however if you have to 
sharpen them, the TBN coating is worn off.  I would  recommend a cobalt bit, and use 
los speed and high pressure. A few drops of  dark cutting oil will also help..
 
Cecil in OKla