Reducing stage sliding friction


First determine if z stage needs to be a little wider or narrower by pushing firmly on the plastic outward and inward (moving the rods about .05mm by squeezing/stretching the entire stage).  Use half or even all of your finger strength.  At the same time with the other hand slide the zslider back and forth to see if friction is lower or higher.
 
To disassemble pop it apart as shown below - insert file and twist.


 
If you had to push outwards (move rods farther apart) then after disassembling file the outside part of the z stage.  If you had to squeeze the stage inwards then file the inner surfaces that hold the rods as shown in this picture .  It's super easy to get this backwards.  The way I think of it is that when you push hard on the lower part with your fingers you are moving the rods and not the sliding stage.  When you file you need to again think of which way you want to move the rods and file on the side that you want the rods to move towards.  You really shouldn't have to do any of this as we do this for you before shipping the kits.
 



You really need a curved file as shown.

Reassemble and repeat as necessary.  Sometimes one side needs more filing than the other.