Power Drawbar Accessory

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Geswearf

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Power drawbar add-ons for benchtop mills seem to be quite pricey and add significant height to the mill (c. 12" - I'm looking at Priesttools PD kit for a PM mill). I'm comparing the price and size to the x or y axis power feeds. I've used a power drawbar on a large Jet knee mill and remember it made a loud hammering noise as it tightened. Priest's are pneumatic, and I'd guess most are.

How do these work? I know it is simply turning the drawbar to pull the collet up into the machined quill. Why are they not a geared motor like the table power feeds?
 
They are all effectively an impact gun. They tighten the drawbar and because it is hitting/ turning fast, there is no need for a spanner on the quill shaft (though it is recommended to put in low gear or apply the spindle brake) no need on mine.

I put a maxitorque on my PM940M. Bought direct from them. Maxitorqe

Worth it. Push button control low where all the other controls are at.

Had to make my own mounting plate/adapter plate.

Pics and thread link

IIRC priest tools turn it into a press release of the collet clamping force, requiring a TTS collet system. READ - the pneumatic cylinder pushes the drawbar down and that opens the collet up to remove/exchange the tooling, then when the pressure is released from the cylinder, spring pressure closes the collet. Hard pass on that for me. Would require a substantial expense in re tooling a lot of my R8 stuff, and a PITA to change out collets.
 
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Sticks said:
Bought direct from them. Maxitorqe

Had to make my own mounting plate/adapter plate.

Pics and thread link

IIRC priest tools turn it into a press release of the collet clamping force, requiring a TTS collet system. READ - the pneumatic cylinder pushes the drawbar down and that opens the collet up to remove/exchange the tooling, then when the pressure is released from the cylinder, spring pressure closes the collet. Hard pass on that for me. Would require a substantial expense in re tooling a lot of my R8 stuff, and a PITA to change out collets.
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I did not see any prices on the Maxitorqe website. I tried selecting one of their units...no luck. Do I have to contact them? How does one measure to hundredths of an inch, the overall length of the drawbar for selecting the appropriate unit. Do I have to find and use calipers large enough for the job or is a steel rule good enough?

Your 'Pics and thread link' did not work. I thought the Priest power drawbar works with the R8 system. Has everyone using this power drawbar changed over?
 
@Geswearf - I fixed the link. Yes, I called them and ordered from them. Price was a schosh under $570 I think. Next cheapest I found was 590.

Steel rule will be close enough to get the drawbar. You are best to call maxitorque and talk to them.

What mill do you have? The top bearing plate and case will be a deciding factor. Needs to be preferably cast, not sheet metal.
 
Sticks said:
@Geswearf - I fixed the link. Yes, I called them and ordered from them. Price was a schosh under $570 I think. Next cheapest I found was 590.

Steel rule will be close enough to get the drawbar. You are best to call maxitorque and talk to them.

What mill do you have? The top bearing plate and case will be a deciding factor. Needs to be preferably cast, not sheet metal.
Click to expand...
Thanks for fixing the link. I'll read your other thread later. I don't have a mill yet, thinking of buying one of the PM machines, but not settled on one yet. I'm trying to get a handle on all of the costs associated with what I'm going to buy.

I'd probably have to make my own top plate - I'd probably mill it out of aluminum or steel, depending on what the folks at maxitorque say.
 
A power drawbar is not a necessity, more of a luxury. If you are doing a thing that requires a lot of tool changes, or repetitive then it's nice to have, but you can still get the work done without.
 
Sticks said:
A power drawbar is not a necessity, more of a luxury. If you are doing a thing that requires a lot of tool changes, or repetitive then it's nice to have, but you can still get the work done without.
Click to expand...
Yes, and @DavidR8's idea of using an air ratchet - or even a battery op drill w/ right angle drive to take up slack then hand wrench - is a good one. And a whole lot cheaper.
 
Geswearf said:
Yes, and @DavidR8's idea of using an air ratchet - or even a battery op drill w/ right angle drive to take up slack then hand wrench - is a good one. And a whole lot cheaper.
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I already had air at my mill for my fog buster so just ran a splitter to add the air ratchet. Easy peasy. Save your money for tooling that really matters like a decent vise and collets.
 
My edit did not stay, and expanding on DavidR8 -

You money is better spent on tooling (endmills, cutters, drill chuck, drill bits,) work set up and hold down (Vise, parallels, T-slot clamp kit), and measuring (calipers, micrometers).

I know there is a saying about buy once, cry once...and it goes both ways. You can blow your wad on a high end quality 6" caliper and micrometers, or get some inexpensive import ones and have money left over for tooling and the like. Upgrade later and at holidays when people ask what you want for birthdays and Christmas.

Harbor freight, amazon and ebay. Shop around for best pricing.

Unless you are getting a Knee Mill, then you really don't need any endmills larger than 1/2".

Is your primary media going to be Steel, Exotics, Aluminum or plastics? Decide that first then Start with HSS (2 and 4 flute) because you will trash them being new.

Decent drill chuck and drill bits (118 pcs)
6" bench grinder to sharpen HSS cutters and drill bits
Fly cutter
Vise appropriate for your mill
123 blocks
small V blocks
T-slot hold down kit
Parallels - fixed and adjustable
6" caliper
Dial indicator, mag base with universal arm, indicol style mount for your quill
carbide scribe
Sharpies
simple adjustable sliding combination square, ruler & protractor Level
machinist measuring set.

Attend YouTube University
And about 15 more excellent online professors.
 
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