Pm 727m issues, help please!

It's probably worth sketching things out and posting on here.

I, for one, am getting confused about what you've aligned/squared, what you've not aligned/squared, which components cannot be adjusted without shimming, and which way out of alignment things currently sit. And why is everyone talking about gibs? Unless they're super loose, not sure why adjusting the gibs would have a sizable effect on alignment.

A sketch would probably benefit you as well to figure out where the misalignment is coming from.

38 thousands might as well be a mile.
 
You may never loosen/ change head tilt, but if the machine takes a big enough bite it can tip it a bit, not to mention, setting it up (I assume you used a cherry picker?) can twist it a bit. I agree jraut, as long as gibs are snug, it's not that, but I think the thread moved away from that culprit. You DO NOT want to shim the column it if the tilt is coming from head.
 
Well i squares the head to the column by using drill rod about 6 inches long indicated the top and bottom of the rod while the Z axis was tightened down at both positiobs. This is they only way i know how to tram the head.
 
Well i got the machine leveled, tried using a piece of drill rod in the collet and that didnt work. Took the gib out and cut half inch off, so i could tighten the gib more, still didnt work. Every time i tighten the clamps in the Z axis it throws the head way off, even when it is clamped in different positions. I called PM and the fella i talked to seems to think i may have a bad gib but is going to talk to matt to see what could be causing the issue. So, hopefully i will hear back from them soon.
 
I had similar with my PM-727..PM said it was normal. Something weird is up there...
 
I hope its not normal, i could live with .002 but not being out .008 everytime i use the clamps. I can see the head nod get lifted up also when i tighten the Z axis clamp. Another odd thing happenes, when i tighten one clamp it will loosen another. I just have to keep going back and forth until both are tight. I just want to figure out a solution. I have work that needs done and i cant do it with the mill being out so far out of square.
 
Yup. That's my method as well, one then the other,back to the first then the other. This is all I could come up with to fell better about the situation...I trammed it after locking it down with this method, as long as I use this method when machining with it, I should be good. I can probably dig out my emails from PM and post it if you like.
 
Here you go...this was about 2 years ago. I did find a way to tighten gibs a gnats hair but....

> I wrote previously and never received an answer.I have a Pm727m and when indicating off the quill, when I tighten the gib locks on the Z, I get somewhere around 30 thou in movement. I tighten the gib as much as possible and it made zero difference. I could really use some ideas as to where to look issues. I cannot detect and movement by hand between quill and Z column but tightening the gibs sure shows it.
> Thank you,
> Sean

Hi Sean,

It sounds like you're saying that when you lock the head down, it's
moving. This would be normal as you're pushing on the head when you lock
it down. You wouldn't be setting up work until the head is locked in the
first place, so this movement should have no effect on your accuracy.
 
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