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Sun Feb 06, 2011 6:22 am

Ok i keep hearing about people rubbing ospho onto their pitted rusty metal .Is phosphoric acid the same thing?When I asked at the paint shop they didn't have a clue about it .Does anyone have pics of the bottles of stuff they use.I have a 60 panel and its really pitted pretty much everywhere

Sun Feb 06, 2011 8:00 am

I think u find it at home depot or harware store ,

Sun Feb 06, 2011 10:47 am

Yeah its the same thing. Just do a quick Google on it...you will get a million examples.

Sun Feb 06, 2011 12:41 pm

home depot sells it by the gallon in the paint section

Sun Feb 06, 2011 12:56 pm

Phosphoric Prep & Etch, 1 gallon container at Home Depot - paint dept.

Sun Feb 06, 2011 1:05 pm

yeah--i use the "klen strip" brand. works well---and its like $15 for a gallon. the cheapest thing you'll have to buy when doing paint & body

Sun Feb 06, 2011 4:07 pm

Thanks guys.

Tue Feb 15, 2011 7:30 am

they are different preparations although ospho has phos. acid in it. you can use straight phos. acid but you have to wash it off with water. you can paint over the ospho after brushing off the white residue. i have tried both and have a case of ospho in the garage. needs to be completely dry before painting over it with no need to use etching proimer, just go with ospho and epoxy primer. phos acid IS cheaper however...

Tue Feb 15, 2011 9:31 am

I believe if you read the directions, your supposed to wash Ospho with water as well. Which is why I prefer Picklex.

Tue Feb 15, 2011 2:28 pm

what does the acid do that your grinder doesnt?

Tue Feb 15, 2011 3:16 pm

micro etch

Tue Feb 15, 2011 3:25 pm

It gets down into the little pits that almost nothing else can reach, and it treats the metal so it wont rust. Converts rust to ferric iron phosphate

Tue Feb 15, 2011 5:38 pm

sorry to disagree but you do not have to wash off the ospho. i just re-read the gallon jug to be sure. no where does it state washing off the product. picklex is great stuff too but i got the ospho first!

Tue Feb 15, 2011 6:03 pm

The Ospho bottle does say to let it dry 24 hours, then paint right over it - but I haven't had very good luck doing that. If there are any drips when applying it, they dry into a sticky blob or trail instead of the white residue and bubble the paint. I've just been treating engine tin with it by spraying it on with a spray bottle, letting it sit, and then hosing off the part outside. Then I dry it off with a shop towel and compressed air - I don't get bubbled paint anymore.

Tue Feb 15, 2011 6:45 pm

ok that makes sense to me will do thanks again

Tue Feb 15, 2011 6:52 pm

that's also why guys prefer light blast..not media or walnut,but fine sand.

you can also "spot" blast instead of treatments...this is a controlled blaster and does not disburse powder and sand everywhere.

I just never really got into the "treatment" methods...i have a unsettled mind knowing the rust is still visable.

but it's still kinda cool how it works!

Wed Feb 16, 2011 7:47 am

tspot100 wrote: sorry to disagree but you do not have to wash off the ospho. i just re-read the gallon jug to be sure. no where does it state washing off the product. picklex is great stuff too but i got the ospho first!

Agreed. I re-read the directions and there is no mention of washing it. When I have used it, I just wiped it on with a damp scotchbrite and scrubbed it in good, let it sit overnight, then follow it up with a maroon scotchbrite the next day to knock off the crust. Always worked ok for me that way. Could have sworn you were supposed to wash it off, but I never did. Nothing in the directions about it though.