Question on Painting aluminum and plastic together

[cheapjeep2]

I have had fantastic results painting aluminum frames, and painting plastic roofs as I take the time to prep it right and use the right materials.

Self etching primer on the aluminum, adhesion promoter on the plastic, etc...

But my question is I am going to paint a roof, can I want to paint the entire room including the aluminum trim around it. So should I tape off the roof and apply self etching primer just the to aluminum first, and then apply adhesion promoter to the plastic or is it possible to use the primer on the plastic and as well or vice versa, the promoter on the aluminum to save a step?

Will it cause any harm if I use self-etching primer on the aluminum and then not mask it off again and apply adhesion promoter to the entire top including over the self-etching primer. Thoughts?

[master66]

The adhesion promoter for the roof will not hurt the aluminum, but the self etching primer most likely will be a bit harsh for the plastic, . Do the self etch first with the plastic masked off and then it doesn't matter what goes over it after that. Or just take the bolts loose from the roof and do each part seperately up until paint. Another option if you really don't want to mask is apply a little self etch by brush in a hidden spot on the roof to test for a reaction.

[cheapjeep2]

Originally Posted by master66

The adhesion promoter for the roof will not hurt the aluminum, but the self etching primer most likely will be a bit harsh for the plastic, . Do the self etch first with the plastic masked off and then it doesn't matter what goes over it after that. Or just take the bolts loose from the roof and do each part seperately up until paint. Another option if you really don't want to mask is apply a little self etch by brush in a hidden spot on the roof to test for a reaction.

Cheers!

[Fishing Dude]

Prime the Alum with zink chomat primer, brushed or rolled not sprayed. Can buy at marine store or out of my garage.