Assemble Z-Motor and Z-Tensioner
Start by pre assembling the 2 z-leadscrews. Each one uses (1) stud-z-leadscrew; (2) m8-nut; (2) m8-washer; (1) Ball Bearing 608, (1) LeadScrew-Timing-Pulley. Build quantity 2 as show below but leaving off the pulley until later. The distance from the bottom of the threaded rod and the bottom of the lower nut should be 25 to 26mm.
Figure 1 - Exploded Leadscrew; Pulley shown for reference, leave off for now.
Figure 2 - Finished Leadscrew
Now attach the leadscrews to the z-motor-bracket making sure to get the orientation correct. The leadscrew is clamped on the bearing using 3 sets of screws/washers/nuts.
Repeat this procedure for the z-tensioner-bracket with the remaining leadscrew.
Figure 3 - Leadscrew mounting on z-tensioner-bracket
Figure 4 - Leadscrew mounted top-view
Figure 5 - Leadscrew mounted bottom-view
Now assemble 2 belt routing bearings on the z-motor-bracket. Each one uses (1) m4x40-cap, (4) m4-washer, (1) m6-nut or spacer, (2) fender-washers, (1) m4-nut. Put a washer on the bolt and run it down into the z-motor-bracket. On the bottom side add the following in order. The m6-nut or spacer, fender-washer, 2 m4-washers, bearing, m4-washer, and finally the m4-nut and tighten. Don’t forget that there are 3 small washers sandwiched between the fender washers, not 2. If you leave one out the belt will rub.
Repeat this procedure for the z-tensioner-bracket except that one of the belt routing bearings will actually go into a slot in the same position as the hole in the z-motor-bracket.
Figure 6- Belt routing bearings exploded
Figure 7 - Belt routing bearings installed on z-motor-bracket
Figure 8 - Belt routing bearings installed on z-tensioner-bracket
Add a drive pulley to a stepper motor. If you don't have your motors yet, this step can be done later. Because of constantly varying suppliers the pulley may vary slightly from the images below. To adjust the depth properly hold the motor in position on the z-motor-bracket and align the pulley so that it is even with the belt routing bearings. Lock the pulley in place via the set screw then mount to the z-motor-bracket as shown using either M3x20 for MakerBot motors, or equivalent for your motors.
Figure 9 - Mounting stepper motor to z-motor-bracket
Figure 9 - Stepper motor on z-motor-bracket
On to Phase 4