[AT] drill bits

[charlie hill]

Good advice John.   I haven't had to buy many drills lately.
(I'll start this old fight again.  The thing that cuts the metal
is a drill.  The thing that turns it is a drill motor and there is
no such thing as a drill bit)

Last time I did have to buy any that were good quality I found
that it's hard to buy a set of various size bits (a drill index) in
decent quality at a decent price.  The only way to get good drills
at a good price is to buy quantities of each size you need.

Charlie

-----Original Message----- 
From: jtchall at nc.rr.com
Sent: Friday, May 01, 2015 5:19 PM
To: Antique tractor email discussion group
Subject: Re: [AT] drill bits

I've been buying all the cutting tools for the machine where I work for the
last 20 years.  First off, never seen a drill that wasn't HSS or carbide.
Coatings are just that. They are intended to help disperse heat but to
primarily keep from the cutting edge wearing down and to prevent chip
galling in  the flutes when drilling aluminum. You most likely aren't going
to find any decent drills locally--if you do the price will be pretty high
most likely. Never seen a decent cutting tool from China or India. There is
a good line of endmills from Korea. The drills I use come from USA, Japan,
Canada, Germany and Mexico. We are a job shop so we need good quality
tooling but don't do large production runs to justify using the extreme
stuff. I keep the shop stocked with Nachi drills up to 1/2", Viking up to
1", whatever is cheapest beyond that. Take a look at MSC, Travers or Enco
and you should be able to find some made in USA drills at a reasonable
price. You'll want jobbers length, most likely 118 deg point, 135 split
points are nice as well but generally found on screw machine length drills.
Get either a bright or black oxide finish. The other coatings are eye candy
on cheap tools to drive the cost up by making you think they will last
longer. Coatings on production grade tooling are a different story all
together. We use black oxide coating on our drills and we cut anything from
plastic to 4140 pre-hard. We actually cut way more tool steel than all other
materials combined. PTD, CLeveland, Chicago Latrobe, Dormer, Ghuring,
Titex--all are great tools, but are going to get expensive quick.

Keep this in mind next time you are drilling. I run a general purpose 1/4"
drill at around 1400 RPM in a rigid setup under flood coolant when drilling
cold rolled steel. With no coolant (cutting oil keeps it lubed but not
really cool), and using a hand drill or drill press (neither of which is
very rigid or runs the tool true), 1400 RPM is too fast.  We can and do push
beyond those limits if the quantity of drilling warrants speeding things up.

John Hall

-----Original Message----- 
From: k7jdj at aol.com
Sent: Thursday, April 30, 2015 2:58 PM
To: at at lists.antique-tractor.com
Subject: [AT] drill bits

I wonder what type of drill bits work for antique tractor bolt removal and
repairs?  I have been buying cheap throw away Harbor Freight titanium
nitride coated bits but have gone back to using high speed steel bits.  Even
the higher quality coated bits don't seem to work as good as the high speed
steel bits.

The coated bits don't drill as well and are much easier to catch and break.
It is getting harder to find high speed steel bits. I have a drill doctor
but it doesn't do a good job on the really small sizes.

Would be interested in what others are using or doing that I might be
missing.

Gary

Renton, WA

JD B
2 Cletrac model F's
1 Cletrac model W

and lots of other old iron
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