Drawbar for PM knee mill

Firstgear

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** I FOUND THE PROBLEM, OPERATOR ERROR, THE QUILL WASNT ALL THE WAY UP........duh!

I have a new PM950 mill and I am finally getting around to get it ready to use. I tried to put a R8 drill chuck in the spindle but by the time I had it threaded in, I wasn’t able to put a wrench on the drawbar. I had to use a socket and a ratchet as the end of the drawbar disappeared below the surface.

Is this correct?

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Here is how far the chuck is drawn up...
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When I use the socket, here is how far it is drawn up into the spindle.
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Comments?


** I FOUND THE PROBLEM, OPERATOR ERROR, THE QUILL WASNT ALL THE WAY UP........duh!
 
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Hmm. Do you have any other R8 stuff to try? I have the 935, and while I wish the drawbar stuck up another inch or so, it never drops that low.
 
Pretty sure the spindle isn't fully retracted; do you have the quill stop set? Another issue that I (and others) have is that the spindle handle doesn't fully retract to the full-up position without help.
 
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Your quill needs to be all the way up to access the drawbar, it moves up and down with the quill. Also holds true for a power drawbar, I bring the quill all the way up and lock it when using the power drawbar, otherwise the quill will move down and be disengage.

Some drawbars may be threaded too long and the R8 chuck/arbor not threaded deep enough, had that happen and destroyed the guide pin and an arbor. Got rid of the guide pin, ASAP. Checked all my arbors to see that they had a long enough threaded section.
 
Your quill needs to be all the way up to access the drawbar, it moves up and down with the quill. Also holds true for a power drawbar, I bring the quill all the way up and lock it when using the power drawbar, otherwise the quill will move down and be disengage.

Some drawbars may be threaded too long and the R8 chuck/arbor not threaded deep enough, had that happen and destroyed the guide pin and an arbor. Got rid of the guide pin, ASAP. Checked all my arbors to see that they had a long enough threaded section.
another dumb question, but why is there a guide pin (set screw in case of PM knee mills)? seems to me that you should just shove the R8 whatever into the spindle, tighten it up and go......what am I Missing? why have the guidepin orient the R8 whatever?
 
That's been debated a lot, and some people remove it. The idea is that it provides a positive stop so that the holder doesn't spin. I had to adjust mine like everyone else, but chose to leave it in place. Having the holder spin will trash the inside of the spindle bore.
 
The OP edited his response, having found the problem.
 
That's been debated a lot, and some people remove it. The idea is that it provides a positive stop so that the holder doesn't spin. I had to adjust mine like everyone else, but chose to leave it in place. Having the holder spin will trash the inside of the spindle bore.
What holder are you talking about spinning? In order to tighten or loosen the drawbar I have to engage the spindle brake.
 
Perhaps the only need for the pin, on any mill with R-8 is when using collets, where there is nothing to hold onto to prevent it rotating along with the drawbar when tightening the collet. I never replaced the pin after it sheared on the Induma mill that I had in my shop; I did not use collets, and besides the spindle had to be removed from the quill to replace it.
 
Ok....that makes sense....
 
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