Z-Height Adjustment for Monoprice Maker Select Printers

Lets you adjust the height of your nozzle with one screw. Eliminates the need to adjust the height of your bed with four screws/knobs. Allows bed adjustment screws to be screwed all the way tight*, greatly increasing the stability of the printing surface.

Supplies needed: 

1 ea.: Frame Top, Frame Bottom, Adjuster Foot, Sensor L Bracket printed in PLA** 

1: 4mm x 30mm screw (https://www.mcmaster.com/94387a262) 

1: 4mm tap (https://www.mcmaster.com/8305a14) 

2: 4mm nuts (https://www.mcmaster.com/90591a255) 

5: 1.91 x 10mm plastite screws*** (https://www.mcmaster.com/99397a267)

Cut threads in the large hole at the bottom right of the Frame Bottom with a 4mm tap or by forcing the 4 x 30mm screw to cut its own threads. 

With your screw in place and its head traveling along the side wall of the Frame Bottom, lock two 4mm nuts together at the end of the 4 x 30mm screw. Add a touch of cyanoacrylate glue if they don't line up well when locked together without adhesive. Put the Adjuster Foot, with the hex hole pointed up, into a shallow bowl and pour boiling water over it. Fit the locked and aligned nuts at the end of your 4 x 30mm screw into the Adjuster Foot after it has been very briefly heated in boiling water. As it cools the Adjuster Foot will shrink to fit over the nuts and no adhesive should be required to keep the Adjuster Foot in place. While still soft, ensure that the Adjuster Foot is straight. If it is crooked when it cools, dunk the Adjuster Foot in boiling water, rip it off the nuts and start over with a new Adjuster Foot (must be printed with PLA to do the above mounting method, otherwise size it up in the x/y directions if needed and glue it onto the nuts).

Clamp the Z-Axis Frame Top and Bottom to the X-axis stepper motor using two 1.91 x 10mm plastite screws. Leave 2+mm gap when starting the first screw into the Frame Top. The other side will have about the same gap, tighten them gradually and evenly until a good grip is made on the stepper motor and your frame is secure.

Move the Monoprice Z-Axis limit switch mount to the outside of the frame, using the original screws coming from the inside of the printer frame. Mount the limit switch to the Sensor L-Bracket using two 1.91 x 10mm plastite screws which in turn mounts to the repositioned (from the inside to the outside of the printer's frame) Monoprice mount by sliding the slot of the L Bracket over the protruding sheet metal feature and threading the original screws used to hold the limit switch in place through the holes in the back of the L Bracket and into the threaded holes in the sheet metal. There is enough slop that finding the threaded holes should be relatively easy.

A third 1.91 x 10mm plastite screw is used to create tension on the 4 x 30mm screw that the Adjuster Foot is mounted to, keeping your adjustment from being changed accidentally.

* don't leave the print surface tightened all the way down (unless it's level ad you don't car to have adjustments available in both directions) ** Duramic PLA is stronger than any other PLA I've used in my 9+ years of 3D printing, letting me screw the frame pieces together very tightly with good grip on the stepper motor *** any ~2mm screw will do but you'll get the best grip using plastite screws which have coarse threads