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Painting chequer plate
Daf - 5/10/18 at 07:35 AM

Morning folks,

I want to paint some ali chequer plate, for painting ali I'd normally key it up with some sand paper and then etch prime it - trouble is it's rather difficult to key up due to the ribs on it. Anybody any experience of an aluminium primer that won't need such a good key or a way to prep the surface?

Cheers


nick205 - 5/10/18 at 08:10 AM

Not painted chequer plate myself before (brush or spray), but have you considered having it powder coated?

Probably won't cost that much and a half decent powder coater should blast clean the plate to prep it for coating. Powder coating is often more durable than home painting as well so you should end up with a better end result.


cliftyhanger - 5/10/18 at 08:12 AM

Frosts do a wash prep stuff, which I think is phosphoric acid.
I would give it a thorough degrease and a bit of acid wash if you can get some. In reality I have no idea if that is better than just etch, but it "feels" right.
Phosphoric acid is way cheaper bought as such rather than as a rust converter or anything else. Or ig you have a agricultural supplier, it is sold as "milkstone remover"


Daf - 5/10/18 at 08:14 AM

Yeah I have thought about getting it powdered, trouble is its going to be in a place where it might get bashed so I'd like to be able to touch it up. The plan for the top coat is a roller finish with truck bed liner paint, it's tough and easy to touch up


nick205 - 5/10/18 at 09:48 AM

quote:
Originally posted by Daf
Yeah I have thought about getting it powdered, trouble is its going to be in a place where it might get bashed so I'd like to be able to touch it up. The plan for the top coat is a roller finish with truck bed liner paint, it's tough and easy to touch up



Fair enough - merely a comment on my part as I've been pleased with powder coating results a few times.


Mr Whippy - 5/10/18 at 05:03 PM

tried it on the landy, even etching with primer, was constantly chipping off when walked on, put down rubber mats instead


bonzoronnie - 5/10/18 at 07:17 PM

Perhaps you will get a nice key if you give the plate a nice de-grease then scour with a decent quality stainless steel wire brush.

Side to side motion then diagonal corners.

Then clean with solvent, that should give a good key for the etch primer.


HAL 1 - 6/10/18 at 08:10 AM

Wire wool or scotchbrite might do the job ok.


Slimy38 - 6/10/18 at 08:26 AM

This might be my ignorance showing, but I thought the point of the etch primer was that the acid content actually makes it's own key? I can understand the clean and degrease to allow the primer to work, but is the manual keying needed?


Daf - 6/10/18 at 10:47 AM

quote:
Originally posted by Slimy38
This might be my ignorance showing, but I thought the point of the etch primer was that the acid content actually makes it's own key? I can understand the clean and degrease to allow the primer to work, but is the manual keying needed?


I'm no expert on paints, but I've tried to paint clean degreased aluminium and also keyed up aluminium and the difference in adhesion is incredible. I know the surface of aluminium corrodes very quickly once exposed to air so perhaps one needs to break through this protective/corroded layer for the primer to stick? Just a guess.

I'm going to give it a go with some scouring pads - I'll report back!