Thread: How to fix this problem, rusted panel?

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Originally Posted by pat mccarthy

take the pits and scrach them out with a nail or awl what will not come out do not worry about it just make sure the naval jelly is not still live wash good dry it and i would push some mar glass or some fiber glass filler in them big pits

I wish I had my camera working it looks good. The pits are like micro pits. I dont think there is one I can get a nail in. There tiny. Thanks

ok then they will be fine just wash and blow them dry

I have got the roof almost ready to paint but have a quick question on spraying. In the morning I am going to give it one more wipe down of phosphoric acid and water to neutralize but the instant it dries it turns a blueish amber color. I believe the amber to be light flash rust. If I give it another pass with a DA and 120 will I be ready? Or should I wait another 24 hours to make sure there is no moisture from the wash off? But if I wait another 24 hours I will have more flash rust.... Confused

Originally Posted by BigTruckDriver

I have got the roof almost ready to paint but have a quick question on spraying. In the morning I am going to give it one more wipe down of phosphoric acid and water to neutralize but the instant it dries it turns a blueish amber color. I believe the amber to be light flash rust. If I give it another pass with a DA and 120 will I be ready? Or should I wait another 24 hours to make sure there is no moisture from the wash off? But if I wait another 24 hours I will have more flash rust.... Confused

blue /gold is ok rust no just da if thats the case blow with air wipe with a pre clean till dry with fresh paper towel with a alcohol base pre cleaner and seal down with epoxy

Originally Posted by BigTruckDriver

. In the morning I am going to give it one more wipe down of phosphoric acid and water to neutralize but the instant it dries it turns a blueish amber color.

That is the chemical reaction between the acid & metal.
I Googled "painting after using phosphoric acid" and most say to wipe the metal down w/alcohol before painting after using phosphoric acid. This removes waxes and oils, removes slight amounts of rust that form between sand blasting and painting, and leaves a thin protective coat of iron phosphate, this is the discoloration you're seeing...joe

Thanks Joe. I see what you mean doing the final sand its all came back to a shiny metal.
I got another question though I am going to give the final wash down with Nason silicone/wax/grease remover . How long do I have to wait until I can spray? This stuff smells like mineral spirits. I am going to park it in the sun with 85 degree weather and let it dry, but how long? Should I primer in the sun and let it dry there or under cover? Thanks

Done but not to happy with it. Today has got to be the windiest day of the year....... I sprayed the ground with water and used a tack cloth before I sprayed but still got lint on it with all the wind. Next time Ill know better prep it and let a paint shop do the spraying indoors. Ill see if I can get MAACO to do a 100-200 dollar paint job on the roof just to cover it. Oh ya , and naval jelly is my friend I love the results I got with out sand blasting. Thanks for the help

Looks a hellva lot better then before.....joe

now see did i steer you wrong .i had to beat it in your head just kidding ..now do not get pi$$ at me.. yes it looks much better

Originally Posted by pat mccarthy

now see did i steer you wrong .i had to beat it in your head just kidding ..now do not get pi$$ at me.. yes it looks much better

Ya , If "I" sand blasted it it would of really screwed up more. Thanks

I was thinking about giveing it a light sanding and spraying another coat of the epoxy primer. Would this be ok or will it have some sort of bonding issues? After sanding would I have to clean again with wax grease remover. I have some primer left over. Thanks

you are going over it with a 2 part primer or you want to sand the epoxy sealer? you need to sand both if your time window is gone some time has past it will not link up so you would want to sand it or at least use a red scuff pad over the spots your going to reshoot

Originally Posted by pat mccarthy

you are going over it with a 2 part primer or you want to sand the epoxy sealer? you need to sand both if your time window is gone some time has past it will not link up so you would want to sand it or at least use a red scuff pad over the spots your going to reshoot

I was going to go over the entire roof with 180 or higher grit sand paper and clean with greasewax remover and spray it with more coat of the epoxy sealer/primer(the same stuff). Not really tying to sand all the primer back down, only sand enough for another coat of primer to stick.

well the stuff i used was ppg DP and you did not want to sand it if you did not have to it was gummy .but i scuff it with a red 3m pad .if your taking primer that made to sand you could hit it with 180 if your cutting down alot of nibs and peel .i never use paper that was to coase for the job. you will just sand all your $$ to dust and then put more on has alot to do if you going to block it out if so 180 is ok for that. if just cutting it down to get somewhat flat then i would move up to a 220 or 320 your sand sanding or DA ? you can move alot of build with 320 and not leave alot of sand marks