I have some aluminium radiator shroud parts that I wish to paint matt or semi gloss black. Can I use something like Tremclad High Temperature spray paint ? Do I need to prime first and if so with what? Tremclad High temp paint specs do not say if priming is needed before spraying it onto aluminium.
I would value your experience on this including names of black heat resistant aluminium spray paints you have had success with!
To get anything to stick to aluminum, it needs to be acid etched, then painted with zinc chromate. Then, you can topcoat that with anything you wish.
I know there are self-etching primers out there. Can they be used without zinc chromate prep???
None that I am aware of: I’ve always just zinc chromated alloy bits.
@Clive_Wilkinson would be a good source of info.
I painted my aluminum CoolCat radiator with ordinary Krylon - the type that claims to be paint & primer.
Has held up fine for 8 or 9 years. I don’t think the radiator and bits really get what is generally called high heat.
Not sure what parts you are referring to but I’m thinking that the shroud itself was done in wrinkle paint (just in case you didn’t know).
The fan supports were dark but perhaps that odd dark brown also used on some suspension parts.
Prime with epoxy after acid etching and you’ll be good to go.
What Nick said. The tech sheets on at least 2 of the common metal preps state that they are aluminum compatible.
Go to Lordco and get some pro form self etching primer ,scrub the alum with scotch bright and wash with dish soap and water , wipe with acetone ,paint away
Alodin is the proper treatment but not nessacary
One part paint 1k air dry is ok but not very chemical resistant compared to a 2 part 2k
Tremclad is 1 part more for lawnmower but ok
A spray bomb for automotive repair would be better in 1k it’s higher quality and don’t get sucked in by high heat paint it’s BS IMHO and I’m not alone