Andy Evans wrote:
I'm not going to tap the holes, because I screw through into a
threaded strip under the top plates, usual 2.5mm holes since it's 19"
subrack stuff.
I like the idea of an earth point underneath, though I don't see why
the anodised surface should suffer from drilling 3mm holes in a drill
press - surely this is pretty low risk? .

The risk is a function of your equipment and skill. :-)

I believe anodizing makes a thin layer of the surface harder than the body
of the metal, and maybe more slippery as well - there's always the chance
that the drill could slp before it bites.


--
Wally
www.wally.myby.co.uk
http://iott.melodolic.com