[Steelmesh]

Installing my new 12Z. I noticed the Y gib was loose (the adjusters weren't even touching the gib) so I setup the X and Y axes just fine. I ran into an issue with the Z-axis gib, it is bottomed out and still not tight (see image below).

I used an indicator on the X and Y axes with them locked down had <0.001" play. With the Z-axis gib fully adjusted and locked down, I get 0.002" play at the spindle; pushing/pulling on the motor. I also didn't notice any change in the amount of force required to raise and lower the Z-axis with the gib at this adjustment.

Am I doing something incorrectly here?


Attachment 271406

[arizonavideo]

I was just playing with mine last night

. If the small end is all the way out on the adjuster then a piece of regular foil as a shim brings it back to the middle.

Cut it to fit the back side of the gib.

[Steelmesh]

I was just playing with mine last night

. If the small end is all the way out on the adjuster then a piece of regular foil as a shim brings it back to the middle.

Cut it to fit the back side of the gib.

Wiki tells me AL foil is about ~.008" thick; thank you for the suggestion I will try it out

[williamsmotower]

Did you get it fixed?

[turbostang]

I am having a similar problem with mine (MD001) that I bought from another member on here. The Z axis was so loose, could see a twist drill deflect the head a LOT when it touched. The gibs were max adjusted already. I took it apart, shimmed it with some .009 shim stock and it was too tight. It would stall/error the servos going up. I ended up cutting up a Dr. Pepper can for shim stock (.004") and it seems a LOT better, but possibly could still use some more. Seems like there's still some fair amount of slack. Y was the same way but seems to have shimmed up nicely...

[Cruiser]

Shimming is the only way to go. Just don't use the side grubs on the shim as they will distort the gib by dimpling and curving them making for a false feel and grabbing.
I fought the Z gibs too and ended up making a major upgrade with rails and such s9ome yrs ago. might find it in the archives and see.

[turbostang]

Cruiser speaks the truth for sure. I have been (still) fighting this for a while now. I still get Z stalls from time to time, but that's a different problem. When I lapped my dovetails/ways on Z - I would check one time and get a half inch or more of variance in the depth of the gib. Finally I took it all back apart and noticed the dimples cruiser spoke of. When the gib went in to a point where the dimples passed their original location, the burr on the gib contacted the back of the slide and took up quite a bit of clearance causing the huge variance in the depth of the gib from one time to the next time.

[Cruiser]

Reading Turbo's reply reminded me of another trick to help with a sticky slide. What I did is so !
first I cleaned the slides and doves with carb and choke spray several times. Lacquer thinner works good too. What you want to achieve is to clean the pores of residual oils. Then I took a piece of leather from an old belt and used it to rub Moly anti seize liberally into the surface of slide ways and gibs and doves. In other words all the friction areas. After I could see a definite colour change. I oiled and readjusted and went to work. The idea is to force the Moly into the pores and reduce the friction . It works.