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July 19, 2011 9:21 p.m. nicksta43 Reader

Well after two weeks or so I've managed to get the little 320i I pulled out of the woods into a smooth running little commuter. Lots of cleaning and checking everything in the fuel system and it is running very well. So now it's time to stick to my original plan and drive it until I am able to afford another dd then pull the BMW off the road to fix the cancer.

However between now and then I do not want things to get worse. It has several spots on the roof ranging from dime to quarter size. It also has several spots around the rest of the body at seams and the like. More concerning is the more structural areas under the rockers and at various pinch welds on the undercarriage. The only rust through at this point is a spot about the size of a pea in the middle of the hood and I want to keep it that way. I know how to fix rust the proper way and have plenty of experience doing so on my last 320 that by any normal persons standards should have went to the scrapyard.

My plan is to attack the easy to reach areas first. Get rid of as much of the surface rust as possible then cover it with either a self etching primer and a paint that matches the original or just cover it with rustoleum and put a matching top coat over that. Just spot repairs but try to blend it in with the original paint so it's not an eye sore and keep it from getting worse until the real repairs take place.

The tough part is going to be the areas at seams and where I'll have to pull things apart to get to. The only plan I have at this point is to clean as well as I can with a wire brush and use some of that rust converter liquid then cover that with rustoleum.

Does that sound like a good plan? Is there a better process?

Keep in mind it could be a couple of years before I can get to the real work because swmbo said she is getting a new car next. This car was on the verge of being a ran when parked submission but I have a soft heart for them and know I can save it, it's just going to take time.
July 19, 2011 9:28 p.m. ansonivan Dork

Trying to restore that thing will eat your wallet and break your heart. Do your best to slow the rust down, enjoy the car and eventually buy a restored or original clean version.

POR15 or a generic version of that will work better than rustoleum to seal the affected areas.
July 19, 2011 9:29 p.m. JoeyM SuperDork

good luck. I hate rust.
July 19, 2011 9:37 p.m. SVreX SuperDork

Is that a bullet hole in the hood?
July 19, 2011 9:44 p.m. nicksta43 Reader

ansonivan wrote:

Trying to restore that thing will eat your wallet and break your heart. Do your best to slow the rust down, enjoy the car and eventually buy a restored or original clean version.

POR15 or a generic version of that will work better than rustoleum to seal the affected areas.

What fun would that be Believe me this one is twice the car my last one started out to be. It's not as bad as it looks. As she sits now

My thought on rustoleum>POR is that it would have the desired affect of slowing down the rust but be easier to remove when the time comes?
July 19, 2011 11:33 p.m. aussiesmg SuperDork

Why would you remove rustoleum?
July 20, 2011 3:16 a.m. Hoop SuperDork

Linseed oil?
July 20, 2011 4:18 a.m. novaderrik Dork

there is a product called "Extend" that stops rust in it's tracks. it comes in a spray can and goes on just like a clear spray paint and turns rust into a black base that's ready for paint.

scrape off as much of the scaly rust as you can with a screwdriver, chisel, wire brush, sandpaper, or whatever.. spray the Extend on it, and cover it with whatever paint you want.
July 20, 2011 6:20 a.m. JoeyM SuperDork

novaderrik wrote:

there is a product called "Extend" that stops rust in it's tracks. it comes in a spray can and goes on just like a clear spray paint and turns rust into a black base that's ready for paint.

Sounds like it turns iron oxide to iron phosphate....which means it is probably mostly phosphoric acid. I'd mask carefully before using, and wear protective gear.
July 20, 2011 6:28 a.m. novaderrik Dork

JoeyM wrote:

novaderrik wrote:

there is a product called "Extend" that stops rust in it's tracks. it comes in a spray can and goes on just like a clear spray paint and turns rust into a black base that's ready for paint.

Sounds like it turns iron oxide to iron phosphate....which means it is probably mostly phosphoric acid. I'd mask carefully before using, and wear protective gear.

i don't know what it's made of or what kind of magic makes it work, but it just runs right off of paint or bare metal and only reacts with the rust. i have seen it at Wal Mart in the past, right next to the touch up paint.
July 20, 2011 6:47 a.m. foxtrapper SuperDork

Should you play with rustoleum rusty metal primer, thin it roughly 50/50 with acetone. Do that and it soaks into the metal and rust real well, and actually dries into a hard finish.
July 20, 2011 12:35 p.m. Jerry From LA HalfDork

SVreX wrote:

Is that a bullet hole in the hood?

Looks more like an exit wound.
July 20, 2011 12:38 p.m. Jerry From LA HalfDork

Also, think about finding a non-runner with a better body and marrying the two since you have it running well. Might save a lot of time and money.
July 20, 2011 12:57 p.m. ultraclyde HalfDork

My dad has used a rust converter (similar to the extend mentioned above) to keep an old chevy truck from returning to the earth quite as quickly. It seems to work well for a while but needs reapplication every couple years. Of course, this truck is 78% rust and he never preps it or topcoats it - just soaks it down and lets it cure.
July 20, 2011 1:31 p.m. GameboyRMH SuperDork

I'll have to see if I can find this Extend stuff, sounds like a more convenient, spray-on version of Naval Jelly.
July 20, 2011 8:45 p.m. nicksta43 Reader

OK i'll pick up some rust converter. I've used it in the past but never held on to the car long enough to see how it holds up. The amount of rust on this car doesn't scare me in the least. I'm from the north and have started projects with way way way more serious rust than this. I have the skills and when the time is right it will be fixed.
July 20, 2011 9:29 p.m. wlkelley3 Dork

I've used extend and other brands of the similar stuff. Not sure what it is made off but it does do the job. Kinda similar to gun blueing process. It does require paint to seal it to prevent further rusting. Problem with just primer over it is primer is porous and it will start rusting again. So rust converter, primer and paint over it, any kind of paint should work. Wire brush/wheel or sand the rust before using rust converter, it will end up smoother that way. Don't get it on any other painted surface you don't intend it on as it will stain the paint. The way you plan on doing it you'll end up with a spotted car but you seem willing to tolerate that for a while. The window areas will take a little time to do right, might have to remove the trim to get to it. If you do it carefully, when the time is right you should only have to fix the bad areas (like the window frames and maybe rockers) and what is now not through the surface will still be not through the surface.
July 20, 2011 9:34 p.m. mad_machine SuperDork

wild how those old e21s rotted. I always liked the looks of them, but have yet to find one that was worth even trying to save
July 21, 2011 2:25 a.m. novaderrik Dork

wlkelley3 wrote:

I've used extend and other brands of the similar stuff. Not sure what it is made off but it does do the job. Kinda similar to gun blueing process. It does require paint to seal it to prevent further rusting. Problem with just primer over it is primer is porous and it will start rusting again. So rust converter, primer and paint over it, any kind of paint should work. Wire brush/wheel or sand the rust before using rust converter, it will end up smoother that way. Don't get it on any other painted surface you don't intend it on as it will stain the paint. The way you plan on doing it you'll end up with a spotted car but you seem willing to tolerate that for a while. The window areas will take a little time to do right, might have to remove the trim to get to it. If you do it carefully, when the time is right you should only have to fix the bad areas (like the window frames and maybe rockers) and what is now not through the surface will still be not through the surface.

he could avoid the spotted car problem by just buying a gallon of Rustoleum paint and a roller..

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