I have a device with a metal chassis using powder coated steel. I need to ground the chassis through a metal hex standoff that makes an electrical connection with PCB ground near a power jack.
We have been using a serrated lock washer on the exterior mounting screw to penetrate the powder coat and make an electrical connection between the chassis and the standoff.
This requires that the serrated washer be placed properly and not lost on subsequent reassembly.
I was looking at switching to the use of a laser engraved spot on the inside of the chassis to allow bare steel to contact the standoff directly, but I am worried that this will be a source of long term corrosion on the steel.
It looks like there are conductive grease corrosion inhibitors that are used on steel, something like NO-OX-ID "A-special".
Does anyone have a better recommendation on how to ground the chassis, or a conductive rust inhibitor that is industry standard?
thanks!