In a machine shop I used to drill 4140 Chrome-Moly with regular
High Speed Steel drill bits. This was in a drill press, I know that it's
a lot tougher with a hand drill on a tower. I still think a regular HSS
drill should work for you. Be careful not to run it too fast and work
harden the surface and also use a cutting oil.
73,
John
-----Original Message-----
From: Charlie Summers
To: towertalk@contesting.com
Sent: 6/18/2001 4:28 PM
Subject: [TowerTalk] Drilling Chrome-Moly Steel
Can someone please tell me what type of drill bit I need to drill out a
5/16" diameter hole in my existing 2" mast with 3/8" wall. I want to go
to
5/8 if possible but the mast may just be too hard.
I would rather stay away from the real expensive, like $150.00, drill
bits,
instead preferring to use several say cobalt tipped or titanium tipped
or
some kind of hardened steel bit.
I have looked at McMaster-Carr's catalog and see what they recommend in
print but was hoping someone would be able to give me guidance based on
experience.
The other hooker is I have to drill this on the top of a tower so
staying
there for hours will not be pleasant, especially with a heavy half inch
drill.
This is a rather personal request on a Tower-Talk related subject so
personal replies might be in order to: w0yg@prolynx.com
Thanks and 73,
Charlie, W0YG..>>
List Sponsor: Are you thinking about installing a tower this summer?
Call us
for information on our fabulous Trylon Titan self-supporting towers - up
to
96-feet for less than $2000! at 888-833-3104 <A
HREF="http://www.ChampionRadio.com";>
www.ChampionRadio.com</A>
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
List Sponsor: Are you thinking about installing a tower this summer? Call us
for information on our fabulous Trylon Titan self-supporting towers - up to
96-feet for less than $2000! at 888-833-3104 <A
HREF="http://www.ChampionRadio.com";>
www.ChampionRadio.com</A>
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
|