As I was building the case for the Tire Pressure Monitoring System (TPMS), I wanted to use brass inserts as threads for the screws holding the printed circuit board (PCB) in place. I had on my To Do list to build the Heat Set Insert Rig on Adafruit and designed by the Ruiz Brothers.
The guide provided by Adafruit is well written and easy to follow. I 3D printed the parts and purchased some items that I did not have. Once I was finished building it, I put it to use adding inserts into my case. The press made it much easer to position and add the brass inserts. The one problem I encountered was I did not leave enough room for the soldering iron to clear the plastic case. Fortunately I was able to work around this issue by inserting a screw into the brass insert and heat the screw instead of directly heating up the brass insert. This did take a bit more time to melt the plastic, but it worked.
I also tried a few things with 3D model for the print to help seat the brass insert a bit easier and keep melted plastic from blocking the end of the threaded insert. I made the hole a bit bigger than the diameter of the screw and made shallow ~1mm depth hole the diameter of the insert. These changes made things go together much easier and position the insert right where it needed to be. In the past, I made the diameter of the hole the same diameter or a bit smaller so the screw could bite into the plastic so the plastic and the insert hold the screw. I did away with that idea this time and made certain that I could align the insert properly and the screw could go all the way through the insert without being blocked.
How do you model your holes for brass inserts?
BTW: Here is a good YouTube video on brass inserts that I liked. I would like to try some of the better brass inserts but I have too many of the cheap ones on hand. I plan to use them up, then try some of the other ones that are specific to 3D printing.
