The case that came with my Ultimate Cart was functional but left a lot to be desired, looks wise. I’d modeled the standard Brown and XE grey cases a while ago so I decided to make them into shells for the Ultimate cart. I added supports and clips to hold them together, poked holes into the models for the SD, button and LED. I think they came out pretty well. I didn’t get to include the bottom edge connector cover for the brown cart, I don’t have the required springs and the tolerances are too tight for FDM printing.
These cases are very detailed, there are grooves and dents all over them, meaning there is no good flat side to position on a print bed to get a reliable print without a huge amount of support waste. I tried 45° and it worked OK but the waste was huge. Putting the print in either of the obvious orientations made the insides impossible to clear out of support material or gave unsightly surfaces to the outsides. Horizontal printing also aligned the layer lines with the clips making them very weak just where they were needed to be strong.
In the end I had to settle on this vertical orientation with a raft for stability and supports to the print bed. It works great, has minimal supports and is easy to post process. It is however, extremely unforgiving to any tolerance issues in your printer setup, you will see the ugly lines in these smooth straight sides if there is even a speck of dust on your rollers!
Once I’d got the cases to print well, I had to solve a couple of bridging issues by adding some fillets in places where the printer was struggling. Now I could move on to the labels.
These are the labels I came up with. The blue one is based on the original Electrotrains design but I switched out the circles for the OSH Hardware logo. You can find all my labels on my label page
Getting the labels to stick to PLA turned out to be a bit of a mission. I tried paper, card, and vinyl labels, all with various kinds of glues and coatings. In the end I settled on regular printer paper with Krylon satin clear coat to protect the ink and 3M Super 77 spray-on adhesive for the glue, those labels aren’t going anywhere!
Here are the glamour shots of the finished cases.
You can download the STL files for the Brown Cart here
You can download the STL files for the Grey Cart here