Tapping Set with chucks for or Mill Drill Press

[jjr2001]

I was about to make a tapping stand and then thought about how it would be used.
Mostly after drilling on the Mill or Drill Press I would tap the holes or use the small
brass threading adapters in the previous thread. Now I already had two Irwin
tap chucks that were designed to be used with 3/8" socket drive handles or ratchets.
These chucks hold very well and I tested the run out in my lathe which was about .004".
So I thought it was worth making another tap adapter for the Mill and Drill Press so that
I would not need to make the tapping stand. Well here it is:

3/8 drill rod for the arbor that will fit in the chuck.
3/8 drill rod for the long and short tommy bars. Why two bars? Well one for smaller taps and
the long one should be good up to about 1/2".
One 3" chunk of Hot rolled for the main housing. Turned it to 7/8" then added the square end
for entry into the Irwin chuck. Drilled and reamed the housing 1.5" deep for the arbor and then
cross drilled and reamed for the tommy bars.

Cheers, JR

[mklotz]

Post withdrawn.

[jjr2001]

Thanks Marv, I like the idea of flutes on the body for use on the smaller taps. I think I will do that mod.
No problem on the other type of tap guides for the smallest taps. I had designed my tapping stand using
your T-handle tap wrench thread. I would have turned down the larger of the two (I have a 3 piece set)
tap wrenches to match the smallest. (not much difference in the ones I have). Then the main shaft for the
tapping stand would have had 3 cross drilled holes in the end that would line up with the T-handle tap wrenches.
I like the Irwin chuck method better since I found it to have less run out than the T-handles. Of course my T-handle
chucks were not Starrett.

Cheers, JR

[mklotz]

I withdrew my post because I felt stupid preaching about small tap wrenches when I hadn't yet read your post about making some.

Nevertheless, it's all good. What's really important is alerting folks to the fact that they can save themselves from a lot of broken taps and drunken threads by the simple expedient of making piloted tap wrenches or adding pilots to existing ones.

[jjr2001]

Your post was fine Marv, no harm no foul. Besides you had a great tip about fluting the tool.

Cheers, JR

[DIYer]

Thanks jjr2001! We've added your Drill Press Tapping Set to our Tapping and Threading category,
as well as to your builder page: jjr2001's Homemade Tools. Your receipt:

Drill Press Tapping Set by jjr2001

tags: drill press, chuck, tapping

[Ralphxyz]

where is the post on making some? ie: making piloted tap wrenches or adding pilots to existing ones.

[mklotz]

where is the post on making some? ie: making piloted tap wrenches or adding pilots to existing ones.

Here's my collection of purpose built piloted holders...

http://www.homemadetools.net/forum/tap-holders-26298

and a description of converting a commercial tap wrench to pin-guided...

http://www.homemadetools.net/forum/t...uide-pin-39232

[CharlesWaugh]

A friend of mine is a 'real machinist' (that is, he actually makes a good living making little pieces of metal out of big pieces of metal).
Years ago, he showed me how to hard tap on a Bridgeport mill. His mill is 3-phase, so all he had to do was tap at a low RPM down into the hole and then reverse the motor at the right instant and the tap backed right out.

Not too easily done when blind-tapping!
:- )


On my drill-press I mounted a 1HP three-phase motor with one of those cheap Ebay VFD's. I can do the same kinda thing, but I have to tap REALLY slow and simply stop the motor, then reverse it. It coats down a turn or so before it stops so I just have to anticipate things a tiny bit.

It'll do full 1" taps happily... in Styrofoam, that is!

Actually, it will 'just' do a 1/2-13 in steel.

Obviously, one has to use a forward-chip-ejecting tap, not your standard auto parts store four-fluted '1-turn in, half-turn out, 1-turn in...'. hand tap.

My only problem is that my Grizzly keyless chuck does tend to let go of the tap when in reverse on the bigger taps, so I have to pop a tap wrench (or vice grips!) on the tap and back it out sometimes. Small price to pay for not having to aove anything or risk a tap getting broken by angling it in the hole.

And I must admit that 8-32 is the smallest I go! No 0-sized taps for me!
: - )

[jjr2001]

Yes indeed. The VFD addition to a drill press,mill, or lathe is a great upgrade.
I added one to my mini lathe when the motor gave it's life. The previous motor was a brushless variable speed DC motor.
The lathe is now much improved due to the increase in torque especially at low speed.

The Drill press was just retrofitted with a 3/4 hp reversible motor. Makes tapping possible on the DP whereas before
I would not tap on the DP.

Cheers, JR