I've got blisters on my hands from taping 20 holes manually and I have
hundreds left to go!
What machine or tools do I need to tap 5/16th-18 holes in aluminum? I
am using T slotted 1.5" square tubular aluminum for a lot of projects,
ranging from a workshed to a photobooth to a workbench and having to
manually tap the ends of this metal is going to kill me! I'm
specifically using http://www.8020.net/T-Slot-1.asp this stuff. I
bought two specialty taps that are a combination drill/tap bit from
www.mcmaster.com part # 2748A43 At $20 each they are pricy and I've
already busted them both after only about 6 holes each with a hand
drill.
Any help please?
You need a drill press and a small Tap-Matic, or drill the holes and use a
hand tap. But why do you need to tap so many holes? Usually the point of
T-slot is that you can use special "nuts" that slide or tilt into the slot.
thanks for the tips on the tapmatic tools. I love this forum already!
While browsing Tapmatics site I noticed tools are often designated
30x, 70x, 90x, etc. What does this number mean? Also I'm wondering if
I can get away with a tapmatic that has a max range of 0-1/4", when
the tap I'm using is 5/16th? Probably not, but since the drill part is
17/64th that is really really close to 1/4".
It's true the Tslot features are nice, but I still have to tap many
ends.
If I bougth this procunier #2 tool off of ebay what is the best place
to buy the 5/16th collette from?
http://cgi.ebay.com/Procunier-No-2-Tapping-Head-for-Drill-Milling-Machine_W0QQitemZ130179513170QQihZ003QQcategoryZ104242QQrdZ1QQssPageNameZWD1VQQcmdZViewItem?_trksid=p1638.m118
Also I remember when I assembled my drill press I fit the chuck on,
but what's the best way to remove it now? Just use a crow bar?
On Tue, 1 Jan 2008 16:45:48 -0800 (PST), snipped-for-privacy@rollandelliott.com
wrote:
=============More than likely you have a Morse taper shank. To remove these
you need a wedge. If you have a large old file and small [#2 MT]
you can some times use the shank. You can also break the file
when you hit it.
for an example of the right tool click on
http://www.use-enco.com/CGI/INPDFF?PMPAGEE7&PARTPG=INLMK32
you are looking for "drill drifts and sets."
Most mill supplies and mail order suppliers will have these in
stock.
http://cgi.ebay.com/Procunier-No-2-Tapping-Head-for-Drill-Milling-Machine_W0QQitemZ130179513170QQihZ003QQcategoryZ104242QQrdZ1QQssPageNameZWD1VQQcmdZViewItem?_trksid=p1638.m118
That one is a little pricey for one without any collets. $75 is more
reasonable.
Ebay collets go out at 8-15 bucks each. Retail on the collets from the usual
suspects (msc, mcmaster carr, etc) is 25 or 26 bucks.
If you don't have a morse taper on your drill press, the procuniers also
come with a 1/2 in straight shank that you just mount in the chuck. I
changed mine to a morse taper because it was too long with the extra length
of the chuck.
Paul K. Dickman
your drill press probably came with a metal wedge, a stamped piece of steel
that is vaguely triangular in shape (if it is a taiwan/china drill press) -
you lower the spindle and find the slot and tap the wedge into the slot to
dislodge the morse taper
Called a "drill drift". If it is an old one of US origin, it
will be forged steel, not stamped steel, and rounded on the top edge to
match the end of the slot in the spindle.
You may have to rotate the chuck (or the pulley on top) to line
up the slot in the spindle with the slot in the outer quill. On my
drill press, it is typically once every five or six changes that I
actually have to rotate it. The rest of the time, it is close enough to
get started, and the drift will rotate the spindle enough to fully
match.
There is even a semi-fancy tool which has a drift welded to the
end of a shaft with a slide hammer on it -- a little easier to use when
you want to devote one hand to catching the chuck or tapping head. :-)
Given the length of the workpiece (which I think that I read in
another branch of this thread late last nigh) -- it sounds as though you
might (if a not too heavy import drill press like mine from Taiwan) want
to lay it down on the floor, with the base rotated to one side (and
probably some 4x4 stacks supporting the column near the head) so you can
drill something longer than the column. The trick of the vise on the
tilted drilling table still should work.
Good Luck,
DoN.
--
Email: < snipped-for-privacy@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
http://cgi.ebay.com/Procunier-No-2-Tapping-Head-for-Drill-Milling-Machine_W0QQitemZ130179513170QQihZ003QQcategoryZ104242QQrdZ1QQssPageNameZWD1VQQcmdZViewItem?_trksid=p1638.m118
JUst crank the quill(shaft the chuck is on) down---there should be a
slot in the side of it, into which you insert a tapered wedge& tap
gently with a hammer.forcing the chuck out. if you don't have the
tapered wedge, better buy one, you'll use it a lot. Jerry
Take a look at
http://www.hitachikoki.com.sg/product_details.jsp?pid 5
I think there are similar products from other vendors.
"Special features: Automatic reversing mechanism backs tap out of
threaded hole at high speed"
As in "pull the trigger to tap the hole and don't let go until the
tap has backed out completely."
I'm retired now, but when I was working, I saw one of our people
using something like this at a job site. DANG if we didn't buy some
nice toys!
Several years back I scrounged a Procunier #2 tapping head off of ebay.
It fits into the Morse 2 socket on my drill press and will do what you want
all day long.
When you pull down the lever on the drillpress, it drives the tap forward at
a one speed. When you lift up on the lever, it reverses and unscrews the tap
at a faster speed.
It is a joy to use and I set it up any time I need to tap more than three
holes.
If you scrounge one used, make sure you get as many collets as you can.
Definitely make sure it comes with the 5/16.
Use spiral point taps and kerosene or wd40 for a lube.
Paul K. Dickman
Dewalt cordless drill. With reverse.
There are tapping machines out there, that look like an air drill on a
swingarm, for production use.
A tapping head on a drill press, can be got cheap if you have time to
shop ebay, or less cheap if needed immediately.
Cheers
Trevor Jones
On Tue, 1 Jan 2008 15:18:47 -0800 (PST), snipped-for-privacy@rollandelliott.com wrote:
First off, I don't understand why you need the combo drill-taps.
Aren't the holes already in the extrusion, ready to be tapped as
required?
I've done a lots of tapping on Item extrusion (though fortunately
never as many as 500 holes at one time) and have found spiral flute
taps to work best by far. See McM p/n 2529A19. Use an aluminum
tapping fluid (e.g., Alumtap), or wax stick lube (McM 1311K1) applied
to the tap.
I do the short lengths held in a fixture with a quick acting clamp
that mounts vertically to the front of a Bridgeport table. Anything
longer than about 3-1/2 feet long would require a hole in the
floor.<g> As has been mentioned, a drill press and tapping head would
also work, but you'd still run into the length limitation.
A *good* 1/2" reversing drill handles the long lengths. It's touchier
and less convenient than tapping on a mill or drill press, but not bad
once you get the hang of it, especially with the proper taps and lube.
Let me know if you'd like a photo of the locating fixture.
Hi Ned I'd love some pics. re AT rollandelliott.com is my email.
You're right the aluminum extrusions are pre drilled so I just need to
tap them and you are also right in recommending the flutted taps. I
just never knew they exsisted!
I guess my dilemna now is whether I should some how rig up my drill
press horizontally with a tapping unit or if I should get one of these
fancy handheld drilling units. I've already busted $50 worth of taps
so I'm a bit aprehensive about using a handheld tool that introduces
wobble and busting more. should that be a concern?
The extrusions I have are 12feet, 8 feet and 4 feet long so if I go
the drill press route I'll deffintely need to put the drill press on
its side. I hope that won't mess up the tapping unit somehow?
Trevor, thanks for the cordless drill advice but Been there and done
that and $50 bucks down the drain :(
Cecil, thanks for the link, at $360 or more I think I'll pass though.
I did find a couple used for half that price though.
George, thanks for the link. I'd never be able to remove that chuck
with out your knowledge. I guess you just take a hammer and bang on
the end of it?
thanks everyone and happy new year!
Well. Dunno what to suggest then.
Work up a set of callusses, maybe. :-)
At least, drill bigger pilot holes. Try to run about 60 percent of the
diameter of the tap for the pilot. Most tap drill charts are at about 75
percent, and if you are drilling any smaller hole than 75 percent thread
engagement, then slap yourself for making life harder than it has to be.
The loss in strength is disproprtionately small, compared to the ease in
tapping that you gain.
I've done a pile of holes, mostly 1/4 inch coarse and fine, and a
right pile of 10-32 ones with a cordless drill.
Done a pile with a reversing Sioux Air drill too, that was even faster.
You twitchy when holding stuff that's supposed to be steady? If so,
work out a way to support yourself for steadiness.
If the volume makes it worthwhile to spend the money, take a look
online for tapping arms. Just ar eversing air motor, with an arm that
keeps it pointed in the right direction. Pretty expensive, but usefull.
Gunpoint taps shoot the chip ahead of the tip, and are used for
tapping through a hole. If you have the clearance behind the hole, use a
starting tap and run it down in one shot, fairly fast. Use a lube. The
Tapmatic Al. stuff works well, as does beeswax, or the cutting lube sticks.
Have fun!
Cheers
Trevor Jones
On Tue, 1 Jan 2008 18:13:25 -0800 (PST), snipped-for-privacy@rollandelliott.com wrote:
The fixture in position for tapping. It mounts in the mill's t-slot
with flat head socket caps:
http://www.suscom-maine.net/~nsimmons/news/ItemFixture01.JPG
The 5/16 dowels fit in the extrusions t-slot and keep it aligned. The
screw with collar on the right clamps in the extrusion's t-slot.
http://www.suscom-maine.net/~nsimmons/news/ItemFixture02.JPG
The fixture in position on the mill table to cross drill for the
fastening sets.
http://www.suscom-maine.net/~nsimmons/news/ItemFixture03.JPG
The dowel pin locates the end of the extrusion to locate the cross
drilled hole.
http://www.suscom-maine.net/~nsimmons/news/ItemFixture04.JPG
A detail of the clamping screw. It's a socket set screw with a collar
loctited in place. The allen wrench for tightening is visible in the
first pic.
On Jan 1, 6:18 pm, snipped-for-privacy@rollandelliott.com wrote:
The only reason sharp taps break in correctly drilled holes is because
the tap is not square to the hole (or you bottom out the tap - silly
mistake).
I've got a large 1/2" drill (corded - tons of torque) with two gear
speeds, variable speed, etc (mine's a Metabo, but everyone makes
them). I've tapped down to M4 reliably (in high gear) under power
without the use of a square, and without breaking the tap with this
thing (soft cast iron, mild steel, 4140).
You have to gain a feel for getting the tap in square. It could take
several holes for you to get the feel, but.... You basically just
gently rock the drill as you start to drive the tap in, and you'll
feel it when the tap kinda *slides* in easily instead of getting a lot
of reverse torque from the drill - this means you're square. If you
don't get this feeling, you're not square and you need to reverse out
and try again - do NOT just ram it in! If you're not confident,
reverse and do it again. You have about four thread pitches from the
tip of the tap to *get it* or else you have gone too far to make any
further angular adjustment.
If the holes are quite deep and you're not too concerned about leaving
chips inside the hole, use a spiral-point tap (most ideal). Spiral-
flute, on the other hand, are good when you want the chips to come out
of the hole (blind hole, or you don't want to dig them out) BUT they
are weaker and typically more expensive than spiral-pointed taps (not
a good situation when you don't have a lot of experience).
Buy a new tap for this job, and don't use it on steel until you're
done (steel work will dull the tap much faster than aluminum). Always!
use lube when tapping aluminum (and pretty much any other metal).
Remember, you can chuck these taps in a reversing drill press, or
milling machine and do the work that way too. It inevitably takes long
to do this type of work on a machine as opposed to by hand, but you
don't have the issues with squareness.
Good luck. 5/16" taps are pretty strong. You shouldn't be breaking
them in aluminum.
Regards,
Robin
Hey Robin,
Thanks for taking the time to write that detailed post. I've got a
new sense of confidence now and I might try the hand drill tapping
machine with your advice.
mcmaster lists the following spiral point taps. I'm guessing 2 flutes
is more ideal than 3 (more room for chips to leave). I'm guessing
cheap $4.68 one will do fine unless someone tells me these coatings
are worth twice the price?
Tap Material Surface Coating/Treatment Thread Length Overall"
#Flutes Each
High-Speed Steel Uncoated (Bright Finish) 1-1/8" 2-23/32" 2
2523A412 $4.68
High-Speed Steel TiN (Titanium Nitride)-Coated 1-1/8" 2-23/32" 2
2762A48 $6.41
High-Speed Steel TiCN (Titanium Carbonitride) 1-1/8" 2-23/32" 3
2568A43 $9.75
High-Speed Steel Oxide-Over-Nitride-Treated 1-1/8" 2-23/32" 3
8300A19 $7.83
Cobalt Steel Uncoated (Bright Finish) 1-1/8" 2-23/32" 2
8779A31 $10.65
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