Fix Broken Screw Holes With 3d Printing Pen

Its happened to all of us (well, anyone that has pried apart a bunch of gadgets and gizmos with hidden latches and screws and not meant to be "user serviceable"): you pry apart a stubborn piece to find you actually broke a joint held together with a screw instead of another clip/latch. In this short instructable I show how I fixed my Logitech Harmony 650 remote using a 3Doodler 3d pen (see other guide on getting the 650's buttons working again).

For my problem, the holes the screws went through ripped open as I pried the heads of the screws through the thin plastic at the top of the remote housing. To fix, we will just fill the resulting break with new plastic, melting it into the existing part, file it down and drill new screw holes through it. If you broke off the post the screw goes in, the fix should be easier: just use a small amount of plastic to re-attach the part (or even just super-glue/epoxy it back in place). With the 3d pen, touch the metal tip to the sides of the break to warm them up and slightly melt them, then add new plastic to fill the area. Use the sides of the pen tip to squish it all flat and weld it to the sides even more. Once its filled and cooled for a minute or two, use needle files to shape it. You want the patch to sit flush so the parts will go back together correctly.

Once the patch is flush and looking good, mark where the screw holes should be. Its best if you can mark/measure this before making the patch (I forgot to, so had to line things up and scratch an X). Drill a small pilot hole to make sure you hit the right spot, then drill the hole to the size of the screw. In my case, I had to go one step further and take a larger bit to create a counter-sink so the glued-on label would stick on flush again.

If you did this right, it should all fit back together and the screws should be holding things snug again! If you messed up drilling the new holes, no worries! Just re-fill with the 3d pen and try again!