[ATM] drilling calipe

[Vicki Smith]

Umm, why not use a starter drill, to get a pilot hole started?? They are very thick, and do not bend. 
And, yes, a carbide drill, would be absolutely best!! Expensive, but best. I use only carbide mill bits, in my shop. 
Val

 
> From: rmay at nethere.com
> To: atm at atmlist.net
> Date: Sat, 4 Sep 2010 12:53:04 -0700
> Subject: Re: [ATM] drilling calipers
> 
> Drilli ng hardened steel is always a bit of fun. It can be done
> with a drill but is much easier done with EDM work. For
> drilling with a bit, try a diamond bit as the best choice.
> Carbide tooling will sometimes do a fair job but you have to run
> that stuff at a very paricular speed (no hand drill motor stuff
> hgere!) with great pressure. Not an easyt job to do so do you
> really need to have the hole?
> Bob May
> 
> rmay at nethere.com
> http: slash /nav.to slash bobmay
> http: slash /bobmay dot astronomy.net
> 
> 
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