I plan to have some steel work that I have been woring on sand-blasted and then powder coated. However, parts of this metal work will then be bolts to other pats, so I am pre-drilling the bolt holes etc.

Do I need to over-size drill holes to allow for the powder-coating material?

I don't want to get it coated only to strip some away by putting a bolt through a hole that is no longer quite big enough.

So, if I do, how much extra should I allow for?

Also, should I assemble moving parts after the coating or can they differentiate at the coating stage? I'm guessing the former, but you never know...

Ta