Pm 727m issues, help please!

Well i didnt get a chance to call PM today, but i was watching alot of videos last night and i think the problem might lie with the mill head not being "square" to the column. This would explain why tram moved when i lower and raise the head. Of course if i square the mill head to the column then instead of tiling the head to tram, i would have to shim the column base.
 
I bought a good tramming tool for my pm727m, made it much easier and faster. It WAS slightly off but that could be existent you're dealing with. That Z axis gib is a but complicated. If you tighten the top you need to loosen the bottom so there is pressure on both sides. The complicated part is getting to the lower gib adjust. You have to slightly pull the bellow away from the column top left (opposite side of quill controls. A tight gun just means your tightening against the opposite side adjuster, not moving it at all. I apply it you've already done this.
I'd recommend the team took tough....
 
Yes i alread adjusted the top gib for z axis, i actually lowered the spindle on about 4 or 5 hockey pucks to take the pressure off then completely loosened the bottom screw, then i tightened the top one till it started to get tigh then just back off alittle and tightened the bottom screw.
 
Well i went and bought a long 3/8 drill bit and cut the shaft off to give me about 6 inches sticking out of the collet rigged my indicator up in my vise and squared the head to the column to within +_.0005 by moving the head up and down while utilizing a torque wrench set at 50 inch pounds to get a consistent clamping pressure. Here come the baffling part, when i put the indicator back into the spindle after indicating the head to the column, i lowered the table to sweep with the indicator. The X axis is off .0038 in 18 inches!!!! Seem like alot doesnt it?
 
It still sounds to me like the column is not square to the base.

If there is no adjustment mechanism on the column, you'll need to shim. (Or scrape, I suppose. But probably best not to get into that sort of thing.)

You can use the 0.0038"/18" to get a first guess as to the thickness of shim required. I don't know what the bolt spacing is on your column, but if it's say 6", you'll need to shim about 1 thou.
 
Sounds like the nod is off to me too. The trouble with the gib is that we can replace it for free, but it will be over-sized and you'll have to fit it to the head's saddle. If it's working as is, I'd just cut off the extra bit. Eventually the gib will wear to the point that the top screw won't be able to prevent it from moving and you'll have to replace it.
 
Well, if its side to side and your head is locked @ 0* (assuming the scale is correct) then shim it. I'd be curious if you just tap the head a little to one side (on the tilt scale) and recheck everything (front to back, side to side) if that's the culprit. Zero is always "0".
 
My machine does have a .004 nod in it, which i intend on shimming but i need to address the x asis first, then ill add shims to bring in the Y axis. My concern with shimming is losing rigidity of the machine base? I loosesned the Zaxis gib, i never move the Z axis while machining so it is always locked in. So, ill have to add .019 worth of shims to the column base then? Anyone else have to add this much? Just seem like alot....
 
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