http://www.truetex.com/drawbar_speed_handle.pdf

Richard J Kinch wrote:
http://www.truetex.com/drawbar_speed_handle.pdf

Ta Muchly. Good idea.

Andrew VK3BFA

Why don't you just use a stubby rachet and 3/4" socket. That's what we
use normally. It has a big advantage when you turn the mill on and
accidently leave the wrench on. The chatering of the ratchet is a great
indicator of you problem and it has little eccentricity so doesn't make
the mill shake violently. Leigh at MarMachine

Why don't you just use a stubby rachet and 3/4" socket.

The round, balanced handle spins on and off quickly. Saves time on every
tool change, like those expensive power drawbars.

Richard J Kinch wrote:

Why don't you just use a stubby ratchet and 3/4" socket.


The round, balanced handle spins on and off quickly. Saves time on every
tool change, like those expensive power drawbars.

So you use a different wrench to crack the drawbar loose, then drop on your
handle, grab it with your right hand, and spin up the mill head with your left
hand? I can see how that would go fast. I did use to do as Leigh did, use a
stubby ratchet with 3/4" socket. If you know what you're doing you can also use
the motor to spin the drawbar off with that, but spinning it on would be a
little risky. :-)

Clever idea.

GWE

Grant Erwin writes:

So you use a different wrench to crack the drawbar loose, then drop on
your handle, grab it with your right hand, and spin up the mill head
with your left hand?

Yep. Usually the 2.5 inch knurled handle is enough for me to get it on and
off; no need for another wrench.

Is there an officially proper torque to tightening the drawbar? Seems to
me it doesn't need much, and if you need a wrench to crack it loose, it
might be too tight. For a collet, it must depend on the area and radius of
contact with the tool. For things like a drill chuck, you're not trying to
grip a tool at all, just seat the taper. And things like a center finder
shouldn't have much drawbar torque in any case.

On Thu, 02 Feb 2006 22:40:21 -0600, Richard J Kinch
wrote:

Grant Erwin writes:

So you use a different wrench to crack the drawbar loose, then drop on
your handle, grab it with your right hand, and spin up the mill head
with your left hand?

Yep. Usually the 2.5 inch knurled handle is enough for me to get it on and
off; no need for another wrench.

Is there an officially proper torque to tightening the drawbar? Seems to
me it doesn't need much, and if you need a wrench to crack it loose, it
might be too tight. For a collet, it must depend on the area and radius of
contact with the tool. For things like a drill chuck, you're not trying to
grip a tool at all, just seat the taper. And things like a center finder
shouldn't have much drawbar torque in any case.
Richard,
I have one Bridgeport I bought new in 1981. I have always used the
wrench to tighten the drawbar. There are many times when it needs to
be way tighter than I could possibly get it with a 2.5 inch knurled
grip. The drawbar is the original one and is still in fine shape. This
is one of the machines I make my living on.
ERS

wrote:
accidently leave the wrench on. The chatering of the ratchet is a great
indicator of you problem and it has little eccentricity so doesn't make
the mill shake violently. Leigh at MarMachine
--That's a great hack; thanks for sharing! :-)

--
"Steamboat Ed" Haas : I can make damn near anything
Hacking the Trailing Edge! : ...except money, sigh.
http://www.nmpproducts.com/intro.htm
---Decks a-wash in a sea of words---

Eric R Snow writes:

There are many times when it needs to
be way tighter than I could possibly get it with a 2.5 inch knurled
grip.

Needed to grip a tool, or seat the taper, or what?

Anyone know what torque the power drawbar add-ons apply?

On Fri, 03 Feb 2006 15:59:26 -0600, Richard J Kinch
wrote:

Eric R Snow writes:

There are many times when it needs to
be way tighter than I could possibly get it with a 2.5 inch knurled
grip.

Needed to grip a tool, or seat the taper, or what?

Anyone know what torque the power drawbar add-ons apply?
Like when taking a heavy cut with a long endmill. E.G. a 3/4 inch dia.
endmill, 3 inch flute length, high spiral, with 2.5 inches of flute
facing a titanium part. Or, 1/2 inch high spiral endmill hogging
aluminum. Both situations will tend to pull the cutter out. I don't
always reef on the drawbar, but it's been tightened pretty tight a lot
in the last 25 years.
ERS

Eric R Snow writes:

Like when taking a heavy cut with a long endmill. E.G. a 3/4 inch dia.
endmill, 3 inch flute length, high spiral, with 2.5 inches of flute
facing a titanium part. Or, 1/2 inch high spiral endmill hogging
aluminum. Both situations will tend to pull the cutter out. I don't
always reef on the drawbar, but it's been tightened pretty tight a lot
in the last 25 years.

I would consider a setscrew holder instead of a collet to hog.

It is pretty easy to overtorque a 7/16 bolt with a hand wrench, so my
intuition is that the drawbar shouldn't be gorilla'd.

On Fri, 03 Feb 2006 23:56:06 -0600, Richard J Kinch
wrote:

Eric R Snow writes:

Like when taking a heavy cut with a long endmill. E.G. a 3/4 inch dia.
endmill, 3 inch flute length, high spiral, with 2.5 inches of flute
facing a titanium part. Or, 1/2 inch high spiral endmill hogging
aluminum. Both situations will tend to pull the cutter out. I don't
always reef on the drawbar, but it's been tightened pretty tight a lot
in the last 25 years.

I would consider a setscrew holder instead of a collet to hog.

It is pretty easy to overtorque a 7/16 bolt with a hand wrench, so my
intuition is that the drawbar shouldn't be gorilla'd.
Well, like I said, I bought this machine new in 1981, it's one of the
machines I use to make a living, and it's still on the original
drawbar. And it's in good shape.
ERS