Z Axis

Structure

The idea is to have 3 columns on which the tool holder will glide. I glued all 4 pieces of MDF together and used a drill press to get the holes exactly right.

My first idea was to have Z axis be mounted on top of X-Y axes.

Tool Holder

The tool fits snuggly into the two holes and is tightened with a plastic red nut.

Motor

I used unipolar Vextra motors. The motor is connected with a thin plastic tube to the theaded rod. The clamp is a metal tape used for holding large pipes to the ceiling. I cut a small piece, bent it, and tightened it with a bolt and a nut.

On the other side I put a thrust bearing in place which takes off load due to gravity from the motor. More on this in the bearings section.

Overall

The rails can be adjusted to tighten the holder, which is a fine balance between a smooth glide and a margin of error due to it being loose. I found that the MDF is good at obsorbing WD40 to stay lubricated. A better solution would of been to make these parts out of plastic, which glides much smoother on metal.

The final version of Z axis is actually mounted stationary to the base.

 

 

 

Failures

My first idea to have the Z axis glide on the X-Y axes was scrapped, because of the advantages of having it mounted stationary.