Even though there are lots of great gears on thingiverse, I couldn't resist the urge to model some too :)

The combinations of parameters are too many to upload an STL for each, so I just picked a few.

I also made a version for helical gears: thingiverse.com/thing:1339

This is the second half of my openscad.org gear sets.

I couldn't get the top and bottom parts of the double helical to union properly, so I ended up offsetting the bottom piece by 0.1mm :( It skeins and prints fine though.

This thing is part of a set:
- spur gears: thingiverse.com/thing:1336

UPDATE: I'm printing some gears and noticed a couple mistakes on the openSCAD script: the variable 'orientation' wasn't doing anything and the value 'extrudeInDiam' was in fact being used as radius. They're both fixed now and I uploaded a new version of the script.

So this is a project I've been thinking about trying out with my robotics club here at Tufts. I played with sumobots a while back in highschool but it turned out to be sort of boring because everyone was using the same kit robot and the same code. The Makerbot is a game changer here. The ability to totally customize a sumobot from the ground up with relatively little effort is awesome. I can't wait to see whole Makerbot sumobot tournaments.

Full disclosure.... this is a relatively difficult print and really pushes the limits of the build size. My makerbot was up to the challenge of the 2.5hr print and resulted in only minor warping but it was definitely a little stressful to watch.

I'm working on another (maybe better, maybe worse) version with multiple parts that slot together which would ensure more uniformity across makerbots.

After having some difficulties with the Plastruder MK3 which comes with the MakerBot, I decided to try to print a better (i.e. more reliable) extruder with and for my MakerBot.

The design was inspired by the "Thermoplast Extruder Version 2.0" from the RepRap project and by photos I saw of Nophead's "Fast extruder" .

(Update: There's now a 4th part to print: InsulatorRetainer.stl)

I published this on the RepRap buliders blob builders.reprap.org/ some days before and was asked to publish it here also.. so here is my post from the Builders blog...

nspired by a paper from Kruth et al. (2005, Benchmarking of different SLS/SLM processes as rapid manufacturing techniques) I also designed a benchmark model for the RepRap. It looks quite random but by printing it you can check whether your RepRap prints geometrically correct. I included the following features:

-vertical holes for M3, M4, M8 screws
-vertical hexagons suitable for M3, M4 M8 nuts
-horizontal teardrops M3, M4 M8 and hexagons for suitable nuts
-sharp edges with angles of 15, 30 and 45 deg
-thin walls 0.5mm, 1,0mm, 1.5mm and 2mm horizontally and vertically
-stair effect at sloped walls with angles of 15, 30, 45, 60 and 80 deg
-round corners, radius 4mm to 16mm
-gear teeth with 2mm wide teeth
-in addition to this, you can also check perpendicularity and parallelism of your printed objects, which were the general intentions of designing a benchmark.

You can download both the STL and the AoI file from SourceForge

/mendel/mechanics/test-parts



Printing it took about two hours, so why not watching a fancy movie while your RepRap prints its benchmark.

The very first version included a complete horizontal hexagon for M8 nuts, but apparently this made the object to big in height, so I just cut it off, leaving just a small offset ;)


The gear teeth were not built as expected but as a round corner with a bubbled rim. I am also missing the 0.5mm thin walls. The 1.5mm walls consist of only two parallel strings and are not solid, there is a small gap between them in both directions.