best way to ground in a plastic project box

What is the best way to ground(chassis) in a plastic box. I have seen some DIY projects that were done in plastic boxes um KEV, looking in your direction as I believe there was a comp you did in a plastic case.
Suggestions?
I
think it should be conductive plastic to work properly but I scored this choice case and would be perfect for a tube mic PSU especially since there was some electronics in it before I took them out. I think they were for a metal ditector or something along those lines. At least thats what i was told. Even has a built in 3 prong so hmmmmm.

when i build (tube stuff) i use a thick wire as a ground and everything connects to it. that wire goes to the chassis ground ones if you have a metal chassis.
for other things care should be taken to ground only ones. works perfect for me. i have build a phono preamp and it has no hum whatsoever.
recently have build an SE el84 amp and it has like almost 5mv(peak peak that is ) hum at the output going to the speakers. and i think its even les beceause i didn't had good probes at hand so probably some hum was picked up by the wires going to the scope.
i suggest using a good thick (1,5mm² to 2,5mm²) wire and bent it so everything can connect to it in a logic way. think of it that you should avoid mixing large and small currents so think logic.
then for the case. if there's something out of conductivmateriaal it shoud be earthed for safety. normaly it should work perfect the only thing that can go wrong is EMC. I have had a problem with that and fixed it by simply using a conductive foil. paste it at the inside so you are protecting sensitive stages and connect it to ground potential.
however thats the way i do things. works for me but there are probably other ways to do it.
if you have trouble that it generates a magnetic field use the same thing.
put some foil to act as a shield and ground that foil.

Or maybe mount all components on a grounded metal plate? (Not touching the plate that is)

Grounding is a non-issue.

shielding is probably an issue.

Same ways they do it in electric guitar bodies.

Spray graphite and make a grounded connection, or line it with foil.

EZ-PZ.

Keef

"Spray graphite and make a grounded connection, or line it with foil. "

Bad Idea>Heat/Vibration>Loose Foil>Short Circuit

Buy A Box

Keef good point like a guitar. Not worried now... I'll have pics once it's done... :thumb: