From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Question on locating and drilling holes for an amateur
Date: Wed, 26 Jan 2000 07:04:40 GMT

If you MUST use a pilot hole..

(Good reasons why....Drill will cut accurately to size even if not perfectly
ground.  Even with web thinning your drill press simply doesn't have the "Push")

Drill a pilot hole only as big as the web..then follow with the full size drill.

Less chance of grabbing, chipping the lip or burning out the drill corners.

Also faster!!

(your Machinist friend is correct)

teenut

Dan Caster wrote:
>
> I was told by a machinist to drill the pilot hole about the diameter
> of the final size drill web, and then to drill the hole with the
> drill that will give you the final size.  I can see the logic to this.
> The drill web doesn't make a chip with some place for the chip to go.
> And if you are doing production work, it is a lot faster to use the
> full width of the cutting edge and get it done.  The big drill will
> also follow the pilot hole, so why go thru a bunch of different
> drills.
>
> So my question is   Are there any books that say that you should
> do it any other way?  And my other question is   What do you say,
> teenut, Scott?
>                                     Dan
>
> --
> When I was a young man,
> I wished I was the son of a rich man.
> But now that I am older,
> I just wish my son were the son of a rich man

From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Question on locating and drilling holes for an amateur
Date: Wed, 26 Jan 2000 18:04:56 GMT

The solid bit down the middle that stops the two flutes from meeting and
producing two interesting spiral fingers.  The end of it is called the "chisel
edge"

teenut

Kevin Szabo wrote:

> In article <c0xj4.304$ps1.61671@news1.rdc1.ga.home.com>,
> Robert Bastow  <"teenut"@ hotmail.com> wrote:
> >
> >Drill a pilot hole only as big as the web..
> > then follow with the full size drill.
> >
> >Less chance of grabbing, chipping the lip or burning out the drill corners.
>
> First dumb question for this wednesday ...
>
> What part of the drill is the `web'?
>
> Thanks,
> Kevin
>
> P.S.  Did you get your son his 'Scope?