Using an epoxy coating to improve boxing

[AC_FX]

Here's something I came up with while getting ready to box up a Rangemaster.  I like using standoffs to locate and secure the board in the box, but the powdercoated boxes I get have overspray and casting marks inside, so self-adhesive standoffs don't have a very smooth/flat surface to stick to.  Sanding them smooth inside the box is kind of a multi-step pain in the ass, and besides, I paint things for a living so I don't need to add any sanding to my life.  To address this, I mixed up a little 30-minute epoxy, poured it in, spread it to cover the whole inside of the box, and let it cure on a level surface.  It flows out to a thin coating, forming a glassy, smooth, flat surface that the standoff really sticks to.

Then I realized there are more benefits to doing this:
1.  This surface is also an insulator between the solder joints on the back of the board and the metal box.
2.  Even this thin layer of epoxy, (the one pictured is less than 1/32" thick) gives me something I can dig the anti-rotation tab on pots into, without drilling through to the outside of the box.  I don't worry about this so much with regular pots, but with the detented 6-way rotary switch on this Rangemaster, it's nice to be able to add that extra protection against rotation of the switch body.  

A couple of cautions - first, don't use too much or you'll end up with a thick layer and run yourself out of room in a shallow box like this 1590B.  Second, drill from the inside with your step drill.  In the photo you can see that two of the holes are bubbled out slightly and have metal shavings trapped between the epoxy and the box - this is from step-drilling from the outside.  It won't cause any problems here, but things like this are generally best avoided.

[adstrum]

Nice idea. I like it.

[negativefx]

Nice!