For a while now I’ve been working to upgrade my toolset, in order to make more interesting robots. One of the projects is 3D printing. Today I’m happy to report the completion of a milestone: I am the proud owner of a home-built 3D printer!
There are so many choices when it comes to 3D printers, that I was nearly paralyzed in moving forward on the project. Then one day the Nova Labs 3-D printing group announced a group build. For $750 we would get the parts for a $2,000 printer (a variant of the MendelMax 1.5), and assemble it ourselves with help from the group. I hesitated a bit — I suspected the build might be rather involved — but I also knew that, claims from MakerBot notwithstanding, there really is no such thing as a great “out of the box” 3D printer. If you want your printer to do well, you have to know how the machine works, and getting your hands dirty is the best way. Having expert guidance was a significant bonus.
So I joined in, and after the usual delays of hackerspace group buys, we started building. I was a little dismayed to find there were no written directions at all! Just a few YouTube videos for a related model, which only covered the hardware part of the build. That meant I had to come in to Nova Labs on Monday or Tuesday to join the build group; I couldn’t do much at home. Sometimes this was inconvenient, but I got to know some great people, all of whom were extremely helpful. Brian Briggman in particular went out of his way to show up at every build meeting and helped dozens of us complete our printers.
There were some difficulties along the way. Some of the frame pieces, being custom, either didn’t fit right at first or needed slightly longer screws. Then I screwed in the RAMPs board too tightly, causing a short — this did not cause permanent damage, fortunately. My first print was a little hairy, as the hot end thermistor had quietly detached itself, and we were therefore heating up the PLA until it smoked. As I was the first person to try printing with PLA, we didn’t know that wasn’t normal! (After that I went through and added strain relief to every wire.)
I have some work left to do. The printer bed is (pretty much) level now, thanks to some washers. I need to confirm the x and y stepper motors are moving the right distance per step. Then the extrusion rate must be calibrated, and this varies with different filaments, so will need to be done many times in the future.
In many respects the biggest challenge is software. If I want to go beyond printing items off of Thingiverse I must learn to to design my own objects. There are many programs for doing 3D CAD design, but one must take the time to learn how to do it, and the options for hobbyists are generally not user friendly. I’ve looked at a few. (It’s worth mentioning here that I found an outstanding free 2D software CAD program, DraftSight. I am told it is a clone of AutoCAD.)
Lots of fun ahead!