Thanks Ray, i will paint aluminium after anodizing.
This way i will have the opportunity for lacer lettering.
Yes nigel, pc cases are fine but i want something suitable for my heatshinks.
I guess you are sending your chassis out for anodizing.
If so, they can anodize them in any colour you like.
Only problem is $$$$$, they usually have a minimum batch price, say 50 or 100 kg; in that case I have left my stuff at the anodizer plant and asked them to run it together with their next job, whatever it is, in that case I pay a nominal fee BUT colour i often a surprise
That said, matte "natural" (aluminum silver no tint) and satin black are very common, so if not in a hurry I can get any of them, generally within the week or 10 days at most.
In fact often they do not even want to charge me (since the real customer pays for the lot job anyway) but I always "forget" a sixpack or a couple "longnecks" (fine wine bottles) on or by the counter ... which makes me always welcome
Or you can straight paint aluminum, secret is properly preparing surface.
In this very moment (just stopped 10 minutes for a cup of coffee) I am about to paint a back panel/heatsink for a 300W Bass amplifier, made out of folded and riveted together 1.5mm aluminum sheet, so it´s 3 mm thick where it matters.
After cutting/folding I washed it well with detergent (to degrease it), and rough steel "sponge" (not steel wool wich is way finer) so as to even surface and mechanically remove top coat (yes, I know new oxide forms instantly), then slightly sanded in a crossing pattern with 120 or 220 grit wet emery paper so as to make surface rough (it always helps adhesion), after punching remaining holes I´ll degrease it again (just pure alcohol and paper towels, simply to remove finger skin grease) , will then apply wash primer, let it dry per instructions (a couple hours) and then final paint.
Much simpler than it sounds, I am just somewhat obsessive with details he he, but nothing more than: cleaning>light sanding (a car shop might sandblast it)>wash primer >final paint.
After a couple days when both wash primer (which reacts with aluminum) and paint have fully dried/cured, adhesion is incredibly good, you need to grind/sand paint off to remove it, not kidding.
While otherwise paint adhesion to aluminum is iffy, think painting on glass or chromed/stainless steel: no *real* adhesion.