I was waiting to see who mentioned this detail first.
Go Harold

Blue chips are bad

that is, drilling low carbon steel with tool steel making blue chips is bad.

The original poster's description of the drill bit as "Titanium Nitride" is
a little inaccurate.
The Bit has a coating of TiN, but the bit itself is still high speed steel.
The TiN helps with wear, but the tool is still limited by its base material.
Besides, I seriously doubt consumer grade TiN coated bits are much better
than commercial grade non-coated...

"Harold & Susan Vordos" wrote in message
...

"Jamie Jackson" wrote in message
...
I've got a lot of drilling to do in iron (?). This is the kind of
metal sold in the hardware store along with angle iron, etc. It rusts
fairly easily, is magnetic, etc. It's 1/2" wide and 1/8" thick or so.
I'm describing it because I don't know exactly what it is (iron or
steel).

Anyway, I've got to drill lots of ~3/16" holes through the stuff, as
well as countersinks for wood screws. Last time, this was really
slow-going and hard on the wrist (I've only got a power hand drill),
especially the countersinking (boring bit is Titanium Nitride,
countersink bit is high speed steel), and the countersink bit dulled
quickly. Should I be using a lubricant, and how do I approximate the
right speed with a hand drill?

My book here says to use lard oil for mild steel (though I don't know
if this is steel or iron), and to use a "medium" speed, whatever that
is. If I've got to use lard oil, where do I find it (will shortening
work)? Hopefully, there's an alternative, considering this is a pretty
low-fat house.

Tips on lubricating while drilling would also be appreciated.

Thanks,
Jamie


Hi Jamie,

You're drill in in steel, mild steel most likely. Typical angle iron is
generally 1020 hot rolled. That is considered low carbon steel (this the
term "mild") and is not heat treatable.

Regards lubrication, I'm not a fan of lard oil, never have been in all my
46 years in the shop. Don't like the smell or the feel. Don't like
the
smell of sulfur based cutting oil either, but I do use it. You can buy
that
at Home Depot I've been told, but I buy it in 5 gallon containers from oil
distributors. Need I say they last a long time?

Drilling by hand is tiresome and not very accurate, but if that's what
you're stuck with, try drilling your hole with a smaller drill and opening
the hole to size. The chisel point of drills makes for tough drilling, so
the smaller the drill the better. Small drills have a smaller chisel
point,
and you're also removing less material, so it goes a lot better. Don't go
too small, though, because drills have a funny way of breaking off as you
push on them. Small ones break very easily.

If your countersink dulled quickly, it's likely from running way too fast,
with a remote possibility of running backwards. That's death on cutting
tools. It's difficult to say what is fast and slow, all depends on the
type of drill motor you're using. If it's a 1/4" capacity, it's likely to
be very fast. Likewise, a gear reduction heavy 1/2" drill motor runs
quite
slow. It would be difficult to say how far to pull the trigger on your
particular drill motor. You get the idea.

A good indicator is if the drill tip or counter sink gets real hot, hot
enough to change surface color. That's definitely running too fast.
Chips that come off should not be colored either, nothing beyond a light
straw color at the most. If they come off blue, again, you're running
way
too fast.

If you have a lot of this work to do, you might entertain the idea of
getting a small drill press. The difference in drilling steel with a
press as compared to hand drilling is unbelievable.

Good luck with the project~

Harold