Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all
the way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2
of them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

RoyJ wrote:
Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all
the way through both walls for convenience. Hand tap with straight
flute tapered tap and 'T' handle. Quick prototype level part, only
making 2 of them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

I dry tap brass 5/16-18 fairly often . Works for me , a sharp tap works best
(duh) .

--

Snag aka OSG #1
'90 Ultra , "Strider"
The road goes on forever ...
none to one to reply

"RoyJ" wrote in message
...
Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all the
way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2 of
them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

No lubricant, no backup (provided your alloy doesn't produce curly
shavings - most don't).

Piece of cake.

--
Jeff R.

That's what I said when a student was taking an hour to get 2 bushings
tapped for the set screws. I got severely yelled at, subject of nasty
e-mails.

Jeff R. wrote:
"RoyJ" wrote in message
...
Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all the
way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2 of
them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

No lubricant, no backup (provided your alloy doesn't produce curly
shavings - most don't).

Piece of cake.

--
Jeff R.

RoyJ wrote:
Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all
the way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2
of them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

There must have been a hundred students at school that have taped
3/4 brass "hammer heads" with 3/8-16 threads over the last many
years without a drop of fluid and without a single "backup" of
the tap. :-)
Also a large number that have done a blind hole in 1/2-20 about
3/4" deep.
If a material dosent make stringy cuttings, no need to back up
a tap. Even if it does that is what a spiral point tap is for. :-)
...lew...

RoyJ wrote in
:

Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all
the way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2
of them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

Do yourself a favor and go buy 2-flute gun taps in all the smaller sizes you
use, and 3-flute gun taps for the larger sizes. They throw the chips in front
of the tap, which means you'll never have to back up in any material unless
it's a blind hole, and then only to empty the chips when you're done. Tap
brass dry, aluminum with kerosene or d-limonene (orange oil), and steel with
Rapid Tap. Once you try gun taps, you'll wonder how they still sell the
standard 4-flute taps.

Ah ha. An improvement! Can you run those in 6-32 or 8-32 in aluminum
with a low speed cordless drill?

If I can get it by the crusty old codger I'll do it.

Bruce Spainhower wrote:
RoyJ wrote in
:

Hope someone can settle an argument: The part is a 1" long x 3/8" OD x
3/16" ID brass bushing that needs a 6-32 set screw. Tap drill goes all
the way through both walls for convenience. Hand tap with straight flute
tapered tap and 'T' handle. Quick prototype level part, only making 2
of them, precision not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3 turn to
break the chip necessary on this part?

Do yourself a favor and go buy 2-flute gun taps in all the smaller sizes you
use, and 3-flute gun taps for the larger sizes. They throw the chips in front
of the tap, which means you'll never have to back up in any material unless
it's a blind hole, and then only to empty the chips when you're done. Tap
brass dry, aluminum with kerosene or d-limonene (orange oil), and steel with
Rapid Tap. Once you try gun taps, you'll wonder how they still sell the
standard 4-flute taps.

"RoyJ" wrote in message
...
Ah ha. An improvement! Can you run those in 6-32 or 8-32
in aluminum with a low speed cordless drill?

If I can get it by the crusty old codger I'll do it.

Bruce Spainhower wrote:
RoyJ wrote in
:
Do yourself a favor and go buy 2-flute gun taps in all
the smaller sizes you use, and 3-flute gun taps for the
larger sizes. They throw the chips in front of the tap,
which means you'll never have to back up in any material
unless it's a blind hole, and then only to empty the
chips when you're done. Tap brass dry, aluminum with
kerosene or d-limonene (orange oil), and steel with Rapid
Tap. Once you try gun taps, you'll wonder how they still
sell the standard 4-flute taps.


Just 10 minutes ago I tapped 16 10-32 through holes in 3/4"
6061 using a 2 flute
tap and a cordless drill. Lube was a couple of drops of
Alumi-cut. No backing up,
just stick it in the #21 hole and tap 3/4" through.

I like it!

BillM wrote:
"RoyJ" wrote in message
...
Ah ha. An improvement! Can you run those in 6-32 or 8-32
in aluminum with a low speed cordless drill?

If I can get it by the crusty old codger I'll do it.

Bruce Spainhower wrote:
RoyJ wrote in
:
Do yourself a favor and go buy 2-flute gun taps in all
the smaller sizes you use, and 3-flute gun taps for the
larger sizes. They throw the chips in front of the tap,
which means you'll never have to back up in any material
unless it's a blind hole, and then only to empty the
chips when you're done. Tap brass dry, aluminum with
kerosene or d-limonene (orange oil), and steel with Rapid
Tap. Once you try gun taps, you'll wonder how they still
sell the standard 4-flute taps.


Just 10 minutes ago I tapped 16 10-32 through holes in 3/4"
6061 using a 2 flute
tap and a cordless drill. Lube was a couple of drops of
Alumi-cut. No backing up,
just stick it in the #21 hole and tap 3/4" through.

I do it every chance I get. My big problem is that the chuck
can't grab the hardened tap well enough. Any thoughts or ideas?
I'm not quite ready to grind 3 flats on the tap.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"RoyJ" wrote in message
...
Ah ha. An improvement! Can you run those in 6-32 or 8-32 in
aluminum with a low speed cordless drill?

If I can get it by the crusty old codger I'll do it.

Bruce Spainhower wrote:
RoyJ wrote in
:

Hope someone can settle an argument: The part is a 1" long x
3/8" OD x 3/16" ID brass bushing that needs a 6-32 set screw.
Tap drill goes all the way through both walls for convenience.
Hand tap with straight flute tapered tap and 'T' handle.
Quick prototype level part, only making 2 of them, precision
not required.

Questions: tap dry or use what lubricant? Backup the usual 1/3
turn to break the chip necessary on this part?

Do yourself a favor and go buy 2-flute gun taps in all the
smaller sizes you use, and 3-flute gun taps for the larger
sizes. They throw the chips in front of the tap, which means
you'll never have to back up in any material unless it's a
blind hole, and then only to empty the chips when you're done.
Tap brass dry, aluminum with kerosene or d-limonene (orange
oil), and steel with Rapid Tap. Once you try gun taps, you'll
wonder how they still sell the standard 4-flute taps.

DanG wrote:
I do it every chance I get. My big problem is that the chuck
can't grab the hardened tap well enough. Any thoughts or ideas?
I'm not quite ready to grind 3 flats on the tap.

That occasional slip has saved my ass a lot, I'm sure!

"DanG" wrote in message
...
I do it every chance I get. My big problem is that the
chuck can't grab the hardened tap well enough. Any
thoughts or ideas? I'm not quite ready to grind 3 flats on
the tap.

Maybe a "tap socket"?? Chuck up a 1/4 hex by 1/4 square
adapter, snap on the
tap socket, insert tap. Find out just how good all those
slip clutch settings really are on
your cordless drill.

http://buy1.snapon.com/catalog/item....&group_ID=1158

I've actually used these before to hold 3/8-16 taps and
drive them with a 3/8 air
butterfly. Worked well in 1/4 steel flatbar.

On 2007-12-03, RoyJ wrote:
Bruce Spainhower wrote:

[ ... ]

Do yourself a favor and go buy 2-flute gun taps in all the smaller sizes you
use, and 3-flute gun taps for the larger sizes. They throw the chips in front
of the tap, which means you'll never have to back up in any material unless
it's a blind hole, and then only to empty the chips when you're done. Tap
brass dry, aluminum with kerosene or d-limonene (orange oil), and steel with
Rapid Tap. Once you try gun taps, you'll wonder how they still sell the
standard 4-flute taps.

Ah ha. An improvement! Can you run those in 6-32 or 8-32 in aluminum
with a low speed cordless drill?

The 8-32 should be no problem. 6-32, however, is the thread
from hell. Someone made a poor choice many years ago when they decided
to stretch the 32 TPI standard all the way down from 10-32 to 6-32. By
the time you get to a #6 screw, the threads remove such a large
percentage of the overall diameter that the resulting thread (and tap)
is quite weak for either side loads or over-torquing. With the tap in a
hand drill (battery powered or with a power cord) it becomes hard to
hold the drill motor in line with the hole for the whole time of tapping
-- especially when you are trying to switch the drill from forward to
reverse.

What would be a much better way to go would be with a tapping
head in a drill press -- but this can run into money if you aren't lucky
about picking up an appropriately sized used one on eBay or at a swap
meet.

If I can get it by the crusty old codger I'll do it.

The gun taps -- pretty likely. The tapping head (if you don't
already have one) --probably not. :-)

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Just got back to checking this thread. Yes, I use gun taps in variable
speed drills all the time. Don's right though. 6-32 is right on the ragged
edge of sensible. It all depends on the alloy you're tapping, how far
you're going, and which lube you use. 1/4" 6061 or thiner, through hole,
proper lube, and a sharp tap, and you can pull the trigger all day long.
Give it a try. At least the 6-32's are inexpensive. As with any tapping
job, keeping the tool aligned to the hole is really important. It's just
that much harder to do with the weight of a cordless drill.

- Bruce

"DoN. Nichols" wrote in
:

Ah ha. An improvement! Can you run those in 6-32 or 8-32 in aluminum
with a low speed cordless drill?

The 8-32 should be no problem. 6-32, however, is the thread
from hell. Someone made a poor choice many years ago when they decided
to stretch the 32 TPI standard all the way down from 10-32 to 6-32. By
the time you get to a #6 screw, the threads remove such a large
percentage of the overall diameter that the resulting thread (and tap)
is quite weak for either side loads or over-torquing. With the tap in a
hand drill (battery powered or with a power cord) it becomes hard to
hold the drill motor in line with the hole for the whole time of tapping
-- especially when you are trying to switch the drill from forward to
reverse.

What would be a much better way to go would be with a tapping
head in a drill press -- but this can run into money if you aren't lucky
about picking up an appropriately sized used one on eBay or at a swap
meet.

If I can get it by the crusty old codger I'll do it.

The gun taps -- pretty likely. The tapping head (if you don't
already have one) --probably not. :-)

Good Luck,
DoN.

In article ,
Bruce Spainhower wrote:

Just got back to checking this thread. Yes, I use gun taps in variable
speed drills all the time. Don's right though. 6-32 is right on the ragged
edge of sensible. It all depends on the alloy you're tapping, how far
you're going, and which lube you use. 1/4" 6061 or thiner, through hole,
proper lube, and a sharp tap, and you can pull the trigger all day long.
Give it a try. At least the 6-32's are inexpensive. As with any tapping
job, keeping the tool aligned to the hole is really important. It's just
that much harder to do with the weight of a cordless drill.

My experience has been that for 6-32 into aluminum, especially if
handheld, thread-forming taps are the way to go. Lube the tap with
sticky wax. I use Lenox saw wax. The thread-forming taps are stronger
than cutting taps, and tend to follow the hole automatically rather than
trying to go off at an angle.

Joe Gwinn


"DoN. Nichols" wrote in
:

Ah ha. An improvement! Can you run those in 6-32 or 8-32 in aluminum
with a low speed cordless drill?

The 8-32 should be no problem. 6-32, however, is the thread
from hell. Someone made a poor choice many years ago when they decided
to stretch the 32 TPI standard all the way down from 10-32 to 6-32. By
the time you get to a #6 screw, the threads remove such a large
percentage of the overall diameter that the resulting thread (and tap)
is quite weak for either side loads or over-torquing. With the tap in a
hand drill (battery powered or with a power cord) it becomes hard to
hold the drill motor in line with the hole for the whole time of tapping
-- especially when you are trying to switch the drill from forward to
reverse.

What would be a much better way to go would be with a tapping
head in a drill press -- but this can run into money if you aren't lucky
about picking up an appropriately sized used one on eBay or at a swap
meet.

If I can get it by the crusty old codger I'll do it.

The gun taps -- pretty likely. The tapping head (if you don't
already have one) --probably not. :-)

Good Luck,
DoN.