Surface prep

[StinKy 0]

Dick: All the foregoing is accurate, in my mind. I refinished heavy const. equip. for a summer, from steamcleaning to sandblasting to priming and topcoating. I also kind of "dabble" on my own vehicles, and used to sell a few I'd done minor bodywork on. I have had good luck w/ Napa's "Extend" for chemcially "locking" the rust in the pits that the sanding discs or wirewheels miss, or that I was too lazy to pursue. I drove one car for a dozen years, and had done this (Extend)prior to priming w/ a gun, and having the car professionally shot, and it mostly kept the rust from coming back on areas that had a chance, like the roof (Fords paint falls off the hoods and roofs, you know). It didn't save the wheelwells, in the end, but they were already too far gone to begin with. Last year I did the roof of my '88 F150, which was simply iron oxide, (zero paint of any type remaining) like a strip mine, and it hasn't bled thru at all to date (one year, no garage). I used two coats of Extend, followed by Rustoleum Dirty Metal Primer, which is allegedly overkill if using Extend, then Rustoleum gloss in a cream color. Of course I sanded/wire-wheeled the roof first, to get all the rust off that would come off. With Extend, you cannot dip the brush back into the main supply or it will all "turn". You must pour some of this Milk o' Magnesia-looking stuff into a sep. container, and use it or lose it. You recoat in like 20 min., it turns from whitish green to black (where it chemically "deactivates" the rust, then it's sandable. I put it on w/ a foam roller (which is also how I put the top coat on the truck--it's moderate "orangepeel" effect, especially when "stroked" w/ a brush to pop the bubbles in the thick Rustoleum, actually looks better than some poor resprays. Sometimes airbubbles form in the Extend--no big deal, as it's very sandable, and you'll be going over it w/ sandable primer anyway. The primer fills any voids in the Extend's outer coat (formed by bubbles) and the inner coat has sealed the rust to begin with. No I don't own Napa stock. Peter

[StinKy 0]

The hood and rear fenders on my 3210-V are moderately rusted. I have been wet sanding for several days on them and what's left is visible discoloration where the rust was and ever so slight pitting that you can barely feel by running a fingernail over it. Would a couple coats of primer fill these imperfections or do I need to use some of that red sanding compound? Also can I apply primer for filler, sand it and re-coat? This is my first serious attempt at a "real" paint job and I'm sure finding out what little I know about it!! Dick

[Dutch 4]

Dick, Without examining the hood, it's hard to give advice. For sure, anything that can be felt will be seen. Wet sanding is usually done on sound finishes prior to applying a top coat. If you have surface rust over a large area, use a power sander and take the entire area down to bare metal (sand several times using finer grit paper each time until you're using 220). Feather edge into the good paint with the 220. Apply metal "etch" to stop the rust. Then apply primer/surfacer. Sand the coats of primer with 220, and keep applying primer and sanding until you get a completely smooth surface. Sand final coat of primer with 320, and you will be ready to apply finish coat (paint). Real deep gouges and "dings" can be filled with a "Bondo" type product BEFORE applying primer. Moderate scratches can be filled with a "putty" AFTER the first coat of primer. Your local auto paint store will give good advice on which products to use. It sounds like a lot of work, but it really isn't when using the proper equipment and materials.

[tmerideth 2]

Dick, I use the muriactic full strength. I have a small "tub", actually one of those plastic storage bins from Wallyworld for 4 or 5 dollars. It does need to be kept outside with a lid on it, secure from any children. If it is kept inside, the fumes will cause oxidation of items that you don't want oxidized. It works really great, is quick, and relatively economical. I am about to purchase a 100 gallon rubbermaid tank that I can put about 20 gallons or so into and be able to totally immerse things like mower deck housings and other larger stuff. You can't beat this stuff for removing rust. I can get the stuff locally for $3.40 per gallon. I haven't tried, but it probably could be cut with water. I have also found that the Lye mixture with water is making a great paint stripper. I also plan to get a second 100 gallon tank and charge it with a caustic solution to strip paint off of pieces that have a lot of rust and bad paint. This way, I will know that the metal is protected and there are no hidden problems lurking underneath all those years of sitting and weathering. The tanks I have found come from a farm supply store and they are pre-drilled with holes around the top flange so that a top can be added and a lock placed to keep out children or other un-authorized individuals.

[StinKy 0]

Thanks for the tips Dutch. I stripped all the old paint off (nasty process) so have just bare steel & rust at present. Didnt know about the etch so will have to do it. I've been useing 150 grit for the sanding so far. I have no bodyworking equip so will have to tuff it out by hand for now. I'll just appreciate it more when done after all the "intimate" contact! Ha Ha. Dick

[Dutch 4]

Tom, I'll keep an eye out for you on the 11 o'clock news. "SC man with vats of acid and lye suspected of body disposal." If you see any "black" choppers over your place, the hazmat and SWAT teams won't be far behind.

[Dutch 4]

Dick, Another product to get is a surface "prep". It removes wax, silicone, and other contaminants without leaving a residue. Clean, clean, clean when painting. Nothing worse than having paint peel, blister, or wrinkle after all that hard work.

[Roy 0]

Phosphoric acid is the basic material in Extend and Naval Jelly that turns rust (iron oxide) into the black rust free iron phosphate. Phosphoric acid is much more benign than muratic acid (no choking fumes). There is a product called "Ospho" that is basically phosphoric acid. I have used all these products except Naval Jelly. They work well. I prefer Extend as it dries quickly. Ospho and phosphoric acid take 24 hours to dry. My 2 cents. Roy

[tmerideth 2]

Dutch, I'll keep a watch out for those choppers. Maybe that 11 o'clock news clip will say something like " SC man devises method to derust and strip a full size Buick. Tractor restorers line up to see SC man's set up." Er, come to think of, I actually live in Podunk, USA.

[tmerideth 2]

Dick, I have found muriactic acid to be an extremely effective and quick rust remover, without damaging paint. I had a cast iron piece off an old attachment that I placed in a plastic vat with muriactic acid. The part had a combination of paint and rust that was both on the surface and some that had bled through the paint. About 10 minutes in the muriatic acid, the part was clean, the good paint still intact, and it is still in good condition now after about 3 months. If you have parts down to bare metal with rust on them, the muriactic will take the rust off almost instantly, but you need to rinse and dry the part thoroughly quickly or it will begin to re-oxidize. Just be careful with the muriatic acid, it has some nasty fumes, and protect your skin. I have had it contact skin without any harmful results, but why take chances. You can find the acid at most hardware stores or the box stores.

[MPH 12]

Dick, When I redid my 112, before I knew of this site, I used a wire wheel on my 4 inch peanut grinder to remove all paint and rust then used self etching primer from local napa. Not much into hand sanding, but 3 coats of primer left it all pretty smooth looking with no swirls. Sure it wouldn't win any restoration contest but it is a workin tractor..MPH

[StinKy 0]

Thanks to all. I'm goin to town this afternoon and stop at the Car Quest and get some etch and prep. I dont think I'll be able to get ALL the little imperfections out but it'll take a "nitpicker" to spot what may be left. Your right MPH, and mine are strictly working class too. Tom, I'll give the muriatic a try when I can get outdoors to work. I still have enough rusty items to give it a test, believe me!! BTW did you cut it or use it full strength? I know it does a great job on masonry. I've used it twice to freshen up my hearth stones. I diluted it a little less than 1/2. Dick

[arnoldir 0]

A note on using rust "converters or stabilizers" DO NOT USE ALUMINUM CONTAINER for the stuff you are brushing on, i.e. pie plates or such. The material reacts with the aluminum and this leads to excessive bubles in the finish. I found this out the hard way when using POR-15. I coated the entire firewall and radiator support on a truck I was restoring, and had to chemically strip the whole darn thing and start from scratch. Now I'll only use the plastic trays left over from TV Dinners or such. My 2 cents.