PM-728V-T table stiction

If any of you are considering making a new gib, and you can't trust the old one as accurate enough to use as a model to get dimensions and angles, watch this before you begin. LOL I've been down this path myself, and at times, been just as befuddled as Max.

 
When the OP tells us what the PM factory said or they answer here themselves, I will comment.
 
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This being Precision Mathews sponsored forum, I don't want to discuss anything negative in here. One needs to be polite. If the OP wants my opinion he can ask in the Reconditioning Forum. Rich
 
Being sponsored does not mean not discussing anything negative, negative, positive, etc it doesnt matter, whatever fixes it.

For the original posted, please wait until our tech resolves it first before making or scraping gibs though, I seriously doubt it is anything like that, not on this high end 728 from Taiwan. Email them at tech@precisionmatthews.com They are off for Thanksgiving in a few hours though so might be next week until you hear back. I will also try to follow up but will not be in the office much this weekend Possibly I would suspect the thrust bearing from what it sounds like, but just a guess. Be sure not to remove any gibs or alter them at all though. I have a customer who pretty much wrecked his machine starting to dig in to things from forum advice about gibs (Not here), it is a mess.
 
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Thank You quality. I completely agree with you. I doubted it was the gibs too. I await what the factory says.
 
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The OP said he removed the gibs and it still has stiction. That should give people the gibs are not the problem.
 
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Hi Folks,

Whether the problem here is the gib or otherwise the two youtube videos posted by @ptrotter and @davidpbest are interesting to watch, but a time investiment! However on one of them the link did not seem to work correctly for me. Here are URLs versions which seemed to take me to the full videos.

www.youtube.com/watch?v=nEDhLlhW2p0 Start watching at 21:50 minutes, this is where he does measurements to see how bad it.
www.youtube.com/watch?v=jYiRM-hJgpU Machining the dovetail after the measurements to reduce some of the wear.
www.youtube.com/watch?v=CGHk0wzIaX4 This is where he tell us that it is a straight forward job to fix a gib!
www.youtube.com/watch?v=lmO3i-KO4Ho This is where they tell us that it was not so straight forward and here is a second try!

Dave L.
 
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Someone asked, so I will comment with the solution.
The customer loosened the mounting bolts for the Y Axis bearing housing / leadscrew mount flange, re-centered it, and tighetened the bolts back up. Problem solved. It was sitting a bit low so not perfectly in line with the travel. Nothing with gibs. Works perfectly now.
 
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