So I have this car from OK that the sun has baked the paint off. Now its cracked and starting to show minor surface rust peaking through. I put a 3M disc on it to start taking it down to the bare metal but in places it has some minor rust staining or very, very minute surface pits the disc will not take out. How do I effectively neutralize or prep these areas for paint??
I've read of using vinegar and water and then rinsing but I'm far from a paint expert. Just posted to follow.
I had the same issue. I purchased NAVAL JELLY. It's a pink phosphoric acid jelly like chemical. Easy to use. You wipe it on bare metal/rust and let it work it's magic. The directions are on the bottle. Neutralize with water after using a wire brush on a drill to remove all traces of rust from pits. Ready for paint after neutralizing. Leaves a phosphoric coating on metal that's perfect to prime over. ( make sure you follow priming directions to be sure it's comparable). Good luck
CLR leaves a residue and needs to be cleaned off well before any painting is considered. Not sure on using it for the OPs purpose.
DuPont Prep-Sol. Why not use a product that was specifically made to do what you want to do? But I'm not a painter.
Can anyone recommend a product that will actually remove automotive primer. I have some paint stripper that cuts right through the paint but doesn't make a dent in the primer.
Prep-sol is a solvent based wax and grease remover. It does nothing to rust. On another forum, the owner of SPI recently said Ospho is a good product for this type of stuff, but he also said you have to be really meticulous in neutralizing it exactly as the instructions say. He says any traces of acid residue left on the surface will react with body fillers and primers and ruin the paint job sooner or later.
Your right, I told you I wasn't a painter. 5717s Metal Conditioner was what I was thinking about. And maybe it doesn't work as well as I thought. http://www.jalopyjournal.com/forum/threads/dupont-5717s-metal-prep.73922/
All kinds of acid and metalready stuff works well if you have the time and follow the instructions for neutralising it before paint. But etching into a deep pit takes a lot of brushing a reaplying acid to go all the way in. Media blasting is still the fastest way if i can choose.
Ospho, Naval Jelly, and Rust Mort, among a whole bunch of other similar products are all phosphoric acid based concoctions. They may have a dye in them (e.g. blue/green color of Rust Mort), or thickeners (e.g. Naval Jelly) or other comparatively inert ingredients, but the active component in each is phosphoric acid. CLR is a mixture of other relatively mild, but still can be dangerous in the wrong hands, acids. They all work similarly in reacting with rust and iron to form an iron phosphate barrier (or other compound with some of the other acids). Here is a link to the Rust Mort page, if you click on the "Tech Data Sheet" you'll see their recommended usage procedure. http://www.semproducts.com/rust-and-corrosion-rust-converters-sealers/rust-morttm The attached link to another thread is a good illustration of one of the draw backs to the web. People who use products incorrectly have an opinion/real experience just like people who use a product correctly. The ones who did it wrong aren't lying, they just don't know what they don't know, and as a result you get folks who say it works great, and those who challenge that notion. The kicker with the phosphoric acid products is washing off the residue with water at the end of the procedure. For some (many?) that's counter intuitive. But it's part of what makes it work, and what ensures that repair/refinish procedures that follow will stand a chance of being successful. Once I was taught how to use it correctly many moons ago I've had great success with surface rust inhibition. Even though most of the products say it won't act as a long term bare metal protectant, I've had, for example. bare metal frames sit in the shop for a couple years with no surface rust development that is visible to the eye. In an abundance of caution I give it another cleaning prior to refinishing, but it wouldn't surprise me if that's not absolutely necessary.............again, depending on cleanliness otherwise.
Do not trust just telling a body shop that you acid treated a car, take a bare shell and HOPE they listened. Make sure you neutralize the acid first. I have seen a few that the body shop acid treated and didn't neutralize. Trust me, the paint will lift and blister!!
I use Ospho frequently. I like the results I get. I just re-read the instructions and nowhere does it say anything about neutralizing it after. All I do is spray or brush on, wipe the drips, let dry, then normal paint prep. So, what say you? Follow the product instructions or the info out there on the web?
Cut and paste from the Ospho.com directions for use: RUSTED METALS - OSPHO is a rust-inhibiting coating - NOT A PAINT You do not have to remove tight rust. Merely remove loose paint and rust scale, dirt, oil, grease and other accumulations with a wire brush - apply a coat of OSPHO as it comes in the container - let dry overnight, then apply whatever paint system you desire. When applied to rusted surfaces, OSPHO causes iron oxide (rust) to chemically change to iron phosphate - an inert, hard substance that turns the metal black. Where rust is exceedingly heavy, two coats of OSPHO may be necessary to thoroughly penetrate and blacken the surface to be painted. A dry, powdery, grayish-white surface usually develops; this is normal - brush off any loose powder before paint application. NEW METALS - For new ferrous or aluminum metals: remove dirt, grease, or oil; apply OSPHO, let dry overnight, then paint. GALVANIZED - where appearance is important, apply one coat of OSPHO, let stand for approximately thirty minutes or until metal is etched. Flush with water, avoiding damage to adjacent areas; or wipe to a smooth finish, let dry, then paint. Where appearance is not important, one coat of OSPHO is recommended to thoroughly coat and etch the metal. Let stand overnight or until completely dry. Brush off any loose powder before painting. A typical paint application will last much longer after an application of OSPHO because subsequent paint coatings attach themselves so tightly that moisture and oxygen cannot attack the metal. OSPHO is water-thin, and therefore goes on easily and covers a larger area than paint. One gallon covers approx. 600 square feet. Historically, best results have been achieved using an oil-base primer and topcoat. Test a trial sample before using under epoxy or latex-base paint applications. OSPHO is equally effective for exterior and interior work alike and is highly recommended as a pre-treatment coating by leading paint manufacturers. For best results, use OSPHO at temperatures no lower than 36 degrees F. Excessive dew and humidity may prolong drying time and cause powdery buildup. Spray equipment should be flushed out with water after using. Clean brushes with water. Avoid getting OSPHO on adjacent areas such as painted surfaces, concrete, masonry and stonework. If splashing occurs, flush immediately with water to remove. WARNING: OSPHO contains phosphoric acid. KEEP OUT OF REACH OF CHILDREN. If taken internally give large quantities of milk or water. Call physician. Avoid contact with eyes. In case of contact, flush with water. Prolonged exposure to skin may cause irritation - use rubber gloves or other forms of skin protection. SAFELY DISSOLVES BLEEDING RUST FROM MANY PAINTED SURFACES: CAUTION: paint composition & quality vary greatly. A check should be made by testing OSPHO on a small area. Dulling or peeling may occur in some finishes. The manufacturer assumes no liability for damage to finished surfaces.
Been using Rust Mort for years, I like the thin(as water) consistency. As has been mentioned in prior posts, complete neutralizing is important, working in small areas at a time and not letting excess into nooks and crannies. It will keep bare metal well protected if stored indoors. Also good for immersing small (lightly) rusted hardware prior to painting.
Hi Ehlien, You should get it sandblasted with Brite Blast, It's silica free made with 100% post consumer used glass. It cuts, unlike sand that actually peens the metal. So you shouldn't have to worry about warping the sheet metal. It will look bright silver and be ready for primmer when finished! Good luck on your build, Joe p.s. This is a car I blasted with it.
Yes I neutralize small areas depending some on the contour of the panel by rinsing thoroughly with clean water, mopping with a CLEAN absorbent towel or squeegy followed immediately with compressed air to total dry. Pay close attention to hidden areas. Discard the mopping towels as they will be to fouled to reuse.
Inside the doors and under the rear windows on my 61 Galaxie have the proper amount of non-through rust. I'll give OSPHO a shot. I'm just gonna rattle can the result but I'm sure it will work.
SPI is some good stuff, I used there 2 part Primer you would swear it was paint when it was dry ,had a nice shine He guarantee you can leave it in the weather for 2 years and moisture would never penetrate it, what ever you have left over you can store in a sealed container up to 72 hrs. and is still spray-able
Re post 20. Blasting has come a long way in recent years with the use of different medians. Is there a build thread on your '34, or more pics and details?
Phosporic acid, neutralize with baking soda dissolved in water while scrubbing with a scotchbrite. Dry, wipe with rubbing alcohol or metal prep to get any residue off. DA the panel, wipe with metal prep, prime.
If you don't want to chemically treat it..... Just use a scrunched up ball of aluminium foil and water to sand/rub it. [you can add a bit of vinegar to the water to speed this up , but not needed] It works a treat. And this method is great for removing rust on chrome [sometimes past the point of no return] The downside............Hard work. you physically have to press and rub hard.
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