What glue/resin do they use in these USB connectors

Thread Starter

Alex Ezorsky

Joined Jul 2, 2019
I've been dissecting some USB 3.0 cables to try and build a right angle connector. I am both frustrated with and in awe of the glue/resin they use to coat the PCB's in these connectors.

In photo 1 below there is a thick cover of something similar to glue-gun glue but much harder and stiffer which is what I admire about it. It melts under a heat gun and turns clear but cools cloudy and hard again. I'd love to know what it is and how to get it.

In photo 2 below you can see underneath there is an even harder fully clear glue layer like a resin or epoxy. It also looks like a great idea to make connectors more rugged.

Any suggestions for resins / glues with this stiffness and for DIY connector applications much appreciated. Hot-glue just doesn't cut it, too rubbery and I can tear it off with my fingernails.


IMG_8442.JPG IMG_8446.JPG


Joined Jan 18, 2008
Could be anything. If it melts without charring with a soldering iron, it is probably a hot melt. If it melts with charring, then maybe an epoxy or other 2-part resin. Is it stiff? Sticky? Burn a little. What does it smell like (e.g. buttery, acrid)? Does it support ignition or just burn while in the flame?