3D print an entire PCB test version to ensure it always fits

Working with Printed Circuit Boards (or PCBs) and ensuring they always work can be a bit of a challenge

When completely stuffed with components little parts can quickly cause problems when being fitted with an enclosure. Usually, the trick is careful measuring. Take some calipers, a piece of paper, and a whole lot of time and you usually come out on top.

But there is another way, as Brad Tarrat over at the i3 Detroit hackerspace shows us; he simply 3D printed an entire replica on his desktop FDM 3D printer. To give a bit of context, Brad is working on a complex BeagleBone setup, and was worried that a few caps might get in the way of his boards stacking up properly. ‘Another use for 3D printing emerges!’ he writes. ‘First print out both sides of the board on regular paper, ensuring the print is 1:1, and that you’ve mirrored the back side. Cut the board outline on one of the sheets of paper and glue it to some sort of cardstock (I used an Elmer’s glue stick). Cut the cardstock and back side, then line up and glue the back side to the cardstock.’

Then it's a simple matter of adding header spacers and the parts that worry you. ‘If you have any real through-hole parts, you can drill holes though the (dried!) paper sandwich and mount them. If you have any real SMT parts you’re worried about placement of, and that you can spare one to test, you can glue them to the board,’ he writes. ‘In this particular instance, I’ve printed a tallish capacitor I was concerned wouldn’t fit between the two boards, and, since I didn’t feel like drilling 92 holes through the board, I printed the spacer parts of the two mezzanine connectors. The Rostock is pretty good at doing accurate sizing in the Z dimension, so the dimension you care about should be upright in your print, if possible (sandpaper and callipers otherwise).’

It's a great and potentially very time-saving idea for working with overly complex builds. The only problem is 3D printing the actual boards, that can be a bit problematic to accurately design the first time. But if you’re regularly running into problems with PCBs, it might be worth the investment. Check out Brad’s success for more inspiration.