I brought my rostock-mini 3D printer home so that I could take it to a class, and while I had it here, I decided to update a few minor things.

First, I swapped out the stepper motor brackets (which also serve as the legs) with three I had designed and printed that were 20mm taller. I have a full RAMPS board under the base plate of the rostock-mini, and although it fits, the fit was “very close”. I didn’t like the fact that my stepper motor wires would touch the surface the printer was sitting on, and the limited airflow paths. This extra 20mm really helps things out, and also opens up the possibility of installing an LCD control panel under the base plate in the front. (If I can figure out how to avoid my bed leveling knobs.)

Second, I upgraded the springs on my adjustable print bed to some that were a bit taller and a bit stiffer. My overall build volume was shortened from 187mm to 185mm, but now I have a lot more range for adjustments and the bed is more rigid (while still allowing the print head to push the spring loaded bed down if it crashes horribly).

Third, I wrapped some plastic spiral wire harness wrap around the wires leading down to the print head, to give them a better visual appearance.

Finally, I changed out my bowden tube from using M4 nuts to hold the tube to using screw in Push To Connect adapters. The goal was to allow me to remove the tube from either end without having to unscrew the plastic part holding the nut in place. However, the cheap PTC adapters I bought appear to be single use, in that they don’t release the tube reliably without breaking, so basically it just makes the bowden tube look slightly more professional.

This is a zip file of the rostock-mini firmware that I am currently using. The only changes I made to it were to update the files to compile with Arduino 1.0.1 and modifications to the configuration.h file to work with the rostock mini.

Rostock Mini Firmware

After replacing the 1/8″ plywood temporary base and top frame plates with the final 1/4″ acrylic , my rostock-mini is working very well! The extra rigidity in the frame has greatly improved it’s positioning accuracy and it’s making prints that rival my Prussa Mendel for quality. The video above shows my round print bed and spring loaded adjustable levelers in action, as well as a close up of the delta bot motion.

This is a picture of the clear acrylic base plate before I added the print bed holder to it.

Here is the complete printer with the adjustable print bed.

I mounted the airtripper v3 bowden extruder cold end on the rear of the top plate. As it turns out, the M6 screw holes on the extruder are close enough to the right distance apart to match up with the idler top end printed bracket, so I can use the same M4 screws (with fender washers) to hold the extruder cold end as well as hold the top plate to the idler bracket! Once I saw that bit of luck I gave up all thoughts of mounting the extruder under the bottom frame plate.