Phosphate Acid Rust Treatment

jims-terrano · 07-05-2018, 02:14

Last week I had a pair of wings shot blasted and the bloke that did it gave me some Phosphate Acid and told me to paint it all over the wings, it’ll take about 18 hours to dry. He then said simply sand it smooth and paint over but the treatment even if left will not let the metal rust again.

I’m used to treatment like Fertan that you need to wash off before painting.

Has anyone got any ideas or knowledge of this stuff. I’ve painted it on and has dried rough so looks like a quick sand down would do the job.

elty001 · 07-05-2018, 06:44

Its a conversion coating that stabilizes the metal prior to painting.
We use an iron phosphate acid dip at work prior to powdercoating.

jims-terrano · 07-05-2018, 08:55

Elty, should I wash it off or just as advised a light sanding to flatten it. I’m a bit worried that paints will react with it.

elty001 · 07-05-2018, 21:22

It depends on the type of application.
Ours is on an 4 stage set up that requires a rinse and oven drying before painting.

07-05-2018, 02:14	#1
jims-terrano Senior Member Join Date: Sep 2004 Location: UK Posts: 12,965	Phosphate Acid Rust Treatment Last week I had a pair of wings shot blasted and the bloke that did it gave me some Phosphate Acid and told me to paint it all over the wings, it’ll take about 18 hours to dry. He then said simply sand it smooth and paint over but the treatment even if left will not let the metal rust again. I’m used to treatment like Fertan that you need to wash off before painting. Has anyone got any ideas or knowledge of this stuff. I’ve painted it on and has dried rough so looks like a quick sand down would do the job.

07-05-2018, 06:44	#2
elty001 Senior Member Join Date: Feb 2008 Location: Aflreton,Derbyshire. Vehicle: 2000se+ 2.7tdi terrano II Posts: 6,832	Its a conversion coating that stabilizes the metal prior to painting. We use an iron phosphate acid dip at work prior to powdercoating.

07-05-2018, 08:55	#3
jims-terrano Senior Member Join Date: Sep 2004 Location: UK Posts: 12,965	Elty, should I wash it off or just as advised a light sanding to flatten it. I’m a bit worried that paints will react with it.

07-05-2018, 21:22	#4
elty001 Senior Member Join Date: Feb 2008 Location: Aflreton,Derbyshire. Vehicle: 2000se+ 2.7tdi terrano II Posts: 6,832	It depends on the type of application. Ours is on an 4 stage set up that requires a rinse and oven drying before painting.