I work in an electronics heavy industry and some of our techs are looking to create ESD safe parts with the ESD resin. I was hoping to find out if heat-set inserts are possible to use after the resin has cured. If not, is there an alternate recommendation for captive fasteners?
If heat-set inserts are possible, is there a guide for hole size?
Also, is there anything in the ESD resin that would be toxic if sanded/post processed? We are hoping to smooth the surfaces after the print is cured. Some ESD filaments use a lot of carbon, so sanding/creating particulate is very discouraged.
We have a blog post specifically about inserting threaded parts into 3D printed objects which should hopefully have some of the information that you’re after! As for the ESD resin, the chemical makeup would still be the same despite sanding; we of course always recommend that one does not inhale or ingest the sanded shavings so you can either wear a respirator of facemask to mitigate any risk there. Proper PPE is always strongly encouraged when working with resin 3D printers and parts.
Heat setting inserts hasn’t worked satisfactorily for me, the few times I’ve tried it (though never in ESD resin).
The cured resin isn’t a thermoplastic, and it doesn’t melt and flow like one. Get the insert too hot and easily ends up set too deep or it slides/skews/tilts off-center in the pocket. Don’t get it hot enough and you get a poorly anchored insert that easily pulls or twists out (depending on whether it’s front-facing or blind).
What I do instead is print the pocket line-to-line with the OD of the insert, and then I wet the outside of the insert with some uncured resin, set it in to the pocket, and when I’m happy with the fit, hit it with a minute or two of a hand-held 50mW 405nm hand-held laser diode thing I bought from a Chinese supplier.
I’ve done buried inserts this way, too. A deep pocket and a printed “plug” to go in to the pocket over the threaded insert after the threaded insert is installed, both components added in post processing with a little uncured resin during assembly and the UV laser to fuse it all solid once it’s assembled.