PM-1054TV max knee travel?

[jeremysf]

Hello!

I have power feed on the z axis of my new PM-1054-TV, which comes with an adjustable limit switch.

I don’t see anywhere in the manual where they talk about any inherent limits on the knee travel (unlike the head travel where they mention a “point of no return” area beyond which the head will require using straps to lift it while adjusting it back into range).

My question is, is the top stop on the knee travel set artificially low? It seems like I should be able to raise the knee so I don’t have the extend the quill to reach small work when mounted in a vise?

Thoughts? Can I safely adjust the top stop and use the upper range of the knee dovetail travel on my PM-1054TV?

Thanks!

This picture is the knee raised to where it hits the adjustable limit switch stop when set as shipped. Seems like there is more vertical travel to go? Is that the limit of the knee lead screw?

I would love to not have to extend the quill (much) to reach smaller work mounted in the vise:

 

[davidpbest]

That power feeder limit stop seems artificially low - by maybe as much as 6”. Take off the limit stop on the power feeder rail and elevate the knee manually. That will tell you the true travel limit.

My guess is that the knee lead screw limit stop is the nut on top of the lead screw. Have a look at this photo - this shows the knee lead screw with a nut on the top end, and the knee elevation shaft coming up from the bottom of the photo terminating in a pinion gear mechanism:

https://flic.kr/p/27Zgqdk

My PM mill (935) will elevate to within 1/2” of the spindle nose with the quill elevated fully. I ditched the Align limit stop rail and used an extrusion for the limit stops that provided full Z-height travel.

 

[MtnBiker]

Look at how the bracket is mounted on my 1054. Compare to yours. Definitely looks too low. You have way more dovetail travel.

 

[pacifica]

Look at how the bracket is mounted on my 1054. Compare to yours. Definitely looks too low. You have way more dovetail travel.View attachment 376677View attachment 376678

How many total inches of travel are you getting from knee? - should be in 17" range.

 

[MtnBiker]

I'd add that they mounted the limit rail (if that's what you call it) on the opposite side as mine. They put it in-between the lock handles. Limits where they could mount it. That limit rail thingy looks like it should be higher or just mount everything on the other side like mine. Kinda weird.

 

[jeremysf]

Look at how the bracket is mounted on my 1054. Compare to yours. Definitely looks too low. You have way more dovetail travel.View attachment 376677View attachment 376678

Super helpful! I moved the stop to the top of its range, and while I do think there is another inch or three of travel more if I got
a longer rail, I think it is plenty fine for me post adjustment.

Now I can raise the knee to the point that a small tool can reach a small work piece with the quill fully retracted and locked:

Thank you to everyone that replied with thoughts and advice!

 

[MtnBiker]

Oddly enough...this solitary activity is really a team sport. You'll find all these extroverted nerds super helpful. Glad you got it solved.

 

[johnnyc14]

Your power feed upper limit switch was definitely set way too low. My old mill has a stop bolt threaded into the column that physically stops the knee from going high enough to allow the knee nut to thread off the top of the screw. It stops pretty much when to top of the dovetail on the knee is even with the top of the dovetail on the column. The bottom of the quill is only about 2 inches from the table with the knee fully raised.

 

[Cletus]

Hey, how do you like that PM vise? Performance decent?

 

[jeremysf]

Hey, how do you like that PM vise? Performance decent?

Well, sadly no, but in talking with PM, we decided it was actually defective / out of spec, so I'm not the one to ask.

The issue for me is the removable part of the fixed jaw had few thou taper to the outside of the bolts, and also the flat surface on the throat of the vise is not parallel to the bed (i.e. it's not parallel to the bottom of the vise) by a few thou.

Precision Matthews was responsive on tech support and we talked through a number of options. Based on what was in stock at PM and with a machine this nice, I decided to upgrade to a Kurt instead.