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.
We have reached another milestone in our RepRap Projekt. Our RepStrap finished printing its first child. The Prusa Mendel v2 is assembled and working.
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:
Our RepStrap nearly finished printing all neccessary parts for its first child, a Prusa Mendel v2. Only the Extruder is missing.
Yesterday Jonas made a short video of the RepStrap printing.
The Printer should primarily serve the purpose to make a ‘real’ RepRap-Prusa from printed parts. Since I managed to get reasonably useful (and mechanically robust) print results, step by step set of parts for a RepRap-Prusa was completed. Further calibration and optimization of print quality took place throughout the process.
Initially we started printing with a spool of PLA-90 from Orbi-Tech – a german supplier for 3D-Printer Filament. They sell this special type of PLA as beeing more heat resistant than standard PLA (getting weak at 90°C). Unfortunately this PLA blend is much harder to print, especially without a heated printbed. Although Orbi-Tech claims this “premium PLA” warps less than standard-PLA, we could not confirm that. So after a lot of fine Tuning and experimenting we switched to white Standard-PLA (from Orbi-Tech as well) for the remaining prints.
In the picture above all parts that are a little darker (light grey) were made of PLA-90. The bright white plastic is the standard-PLA.
Well, that’s awesome. I have never seen a 3D printer live before – and now this bootstrapped contraption on my desk is fabricating three-dimensional objects from plastic.
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.
It must have been about a year ago that I (again) stumbled across the RepRap project. If you ask Jonas, this was probably the key moment, when it grabbed me to build my own 3D printer. Since I can remember we have dreamed up technical projects together that failed to realize due to an absence of a full featured mechanical workshop.
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.
