After the success of my first instructable, a fully functional LEGO 3D printer, I was planning to make some improvements.
At first I was planning to replace the Z-axis threaded rods by cnc lead screws. This should result in a smoother z axis motion. With an improved accuracy of the prints in the height.
A next step would be an improvement in the X-axis. To allow more weight on top of the carrier. I was going to modify the Extruder-carrier from standing to lying. Additionally this also would have made room for a second extruder.
All this, until a colleague pointed me to the Remix Contest. Along with the question whether my printer could print chocolate. This resulted in a second version of the "3D chocolate printer made from LEGO" made by Saul (April 2005). He ends his instructable with: hopefully someone will rebuild this and simplify it.
It's 2015, and thus the original instructable is over 10 years old, still gets replies, but nobody made such a printer. Since I already made a LEGO 3D printer, all I had to do was build a chocolate extruder :)
Unfortunately, printing chocolate isn't easy.
But it can be done. And basically there are two ways to print chocolate (at home):
Without a heating system, the chocolate will solidify sooner with a worm screw. The chocolate will also be in touch with more LEGO. Also this requires the extruder to be disassembled and cleaned after each print.
That's why I've chosen the second option. This version is also the easiest to make with LEGO. In addition, the chocolate remains edible. And that's what it's all about.
The best way to gain knowledge of a 3D printer, is to build one. Building this LEGO 3D printer taught me alot about all aspects of 3D printing. Even making mistakes was part of the learning. The advantage of LEGO is that it's easy to change parts of the design.
I can therefore recommend, for anyone interested in 3D printing or robotics, to experiment with LEGO, Arduino and Nema Steppers.