Last night I moved my goldfish aquarium to my new home. During reassembly of the pump a small clip that secures the sealing bracket on my “EHEIM eco pro” aquarium filter broke. I had to quickly fix this since the fishes were waiting in their transport container and urgently needed some fresh and circulated water.

A great opportunity to test my RepRap workflow!

I removed the broken part, took some measurements, drafted a replacement in OpenSCAD and printed it on my RepStrap in ABS. From idea to completion in 45 minutes. I suspect that it would have taken longer to even find a spare part supplier. Order and delivery not included.

I published all files on thingiverse: http://www.thingiverse.com/thing:16119

Last two challenges had to be overcome: Because the RepStrap still has no heated printbed the Prusa x-carriage had to be made from PLA. Which is not the best choice when faced by the heat radiation from a heatbed at up to 110°C and extruder temperatures beyond 200°C. Fortunately the carriage survived just long enough to get its ABS-replacement printed on the Prusa itself.

The same applies for the Extruder body: The PLA version did not withstand the heat long enough so we temporarily replaced it with the RepStrap’s extruder. This way we could print an ABS-extruder (seen in the picture below; there are still some warping-issues since the power supply was not capable of heating the printbed up to our desired temperature)

During the assembly of the Prusa, we decided to substitute some of the parts with better replacements than provided by the original Prusa repository. These are:

• MakerGear-Prusa-Mendel ball-bearing support for z-axis lead screw
  (lower-z-bar-clamp-left.stl, lower-z-bar-clamp-right.stl)
• Lm8uu X Carriage with Fan Mount for Prusa Mendel by tommyc
• Accessible Wade’s Extruder 9/47 by Stoffel15

Absolutely fascinating.

Time passed quickly last week, so i’ll try to give a brief summary of the final steps to a working RepStrap 3D printer.

When our RAMPS-board and microcontroller arrived last week, the electronics were completed. The PCBs came pre-assembled, so i just had to stick the Stepper drivers in place, add a little cooler on top of each and solder some female connectors onto the stepper cables and opto-endstops. I crimped the hotend heat resistor and thermistor onto their cable instead of soldering due to high temperatures near the heater block.

As a power source i pulled an old ATX computer power supply from the junk box. There is a great page in the RepRapWiki on how to wire those up.

That’s for the hardware. On my Controller i installed Sprinter, a powerful and extensivley tested RepRap firmware. As a computer-toolchain i am testing SFACT (Slicer) and Pronterface (RepRap host software). For now i am quite happy with those.

In further posts i’ll go into more detail on the first extrusion, my first spool of filament and tuning all the parameters for good print quality.

But being able to make free-form objects from plastic right on the desk, that changes everything.

A few months later I had read deeply enough - and Jonas infected. We started developing our own RepStrap - strongly inspired by the RepRap Mendel design. And this is the result so far:

The frame is entirely made of materials from a local hardware store. The linear bearings on all axes are based on standard 608-ballbearings, aluminum profile and threaded rods. Stepper motors, timing belts were purchased as well as the extruder and hot end for lack of time.

Only thing missing is the RAMPS-1.4 electronics that should be delivered from reprapworld.com these days.

Jonas and I will continue to document the ongoing build process and portray our work done to date.