An HSS type should do the job. You have to use some oil to avoid 
burning/overheating the drill though. If you want to be a little fancy you can 
buy a carbon-nitride drill bit. They, usually, are gold colored and come with 
"life-time warranty" how much that now is worth. You should still use oil 
during the drilling as that extend the lifetime of the drill quite a lot.
An other avenue is to resharpen the drill after it gets dull, but that requires 
a grinder and some skill. You get good at it after some time though.
Hans - N2JFS
 
 
-----Original Message-----
From: Guy Molinari <guy_molinari@hotmail.com>
To: towertalk@contesting.com
Sent: Tue, Mar 23, 2010 11:11 pm
Subject: [TowerTalk] Drill bits
Hi all,
    I don't know why this is so hard.   I'm trying to drill out some hole on 
some 3/8" steel plates that I'm going to have galvanized.   I bought a 13/32" 
drill bit and it worked great for about 10 holes or so.   The problem is that I 
have about 140 more to go.   Any recommendations on a good quality drill bit?   
 
73,
Guy, N7ZG
                      
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