Geeetech

Hi all just finished building the printer but seem to have a few issues, the auto home on the Y axis runs to the opposite end of the end stop and I cannot get the Z axis to move more than a couple of mm before it jams, the motors seem to go out of sync, any help on this would be great.

Loosen the screws in the z axis nuts in the carriages, this will help a bit. Also, make sure the axis coupler is not ex-center, so the rod should be in the middle
On the long term you will probably need a "z wobble fix" part from thingiverse.