The nylon Acme Nut is so tight it took me for 1/2 hr to get it to screw up and down screw(still tight), then after setting there a hour or so it is really hard to move again. no lube to see if that helps. Also no set screw on coupling just compression clamp, had trouble with slipping because Acme Nut so tight. Also there are insets in back of the Acme Nut, are there shims or spacers required to mount to gantry?
As a note to builder after assembling the z axis you will need to remove the bottom bracket to mount on gantry.
The self tapping screws only use 1 taping thread and maybe 2 other treads through the gantry I hope this will hold. I assume from the note in assembly notes that you want the 2 tee nuts are in the top of each 20x60's and the 90's are facing each other to help give the double beam support but I have not seen this in any pictures.
There are 12 1/8" spacers my guess is for the stepper motors but no pictures to verify.
Not sure what Router Spacers are used for, unless for hold work piece in place.
Lack of assembly instructions is very frustrating.
I am very happy with the quality of the kit (except the Acme Nut)
I am very happy with the quality of the kit (except the Acme Nut)