Recommendations on Removing Rust, and Applying Primer and Chassis Paint 1937 Pontiac

[Guest bofusmosby]

When I first got my car (3-4 years ago) my car was pretty much a rust-free car. This also included the chassis, and everything else under the car. Well, after being subjected to the heat and humidity of Florida, the entire underside of the car (including the frame) has developed a coat of rust that needs to be stopped before it gets any worse. I figured on using a wire brush and Kerosene to get the surface rust off best I can, then apply a coating of chassis paint to protect the undersides. Most (if not all) of the rust appears to be surface rust, so do I use some kind of encapsulator before I apply the chassis paint? Do I use a primer? I will probably have to use either a foam paint brush, or maybe a rattle-can for these coatings. I have a few questions about this process, and would appreciate any and all help and opinions on these.

1....After washing the underside with kerosene and a wire brush to remove the oil, grease, loose rust etc, does the Kerosene leave any kind of residue that will then have to be removed before any coatings are applied? If so, any recomendations on what to use for this?

2....Will I need to apply a rust encapsulator, or just a good rust primer before the top coat? Any recommendations?

3....Will I use a flat black, semi-gloss, or high gloss? Which would be period correct?

4....Do I paint the entire underside of the car, and all with the same color/gloss? Is there anything that I should not pain, with the exception of the exhaust and muffler. Of course I assume that this also goes for the underside of the fenders as well. Since the original color of the car was black, in the future I will be bringing it back to the original color, so even if the underside of the fenders were originally the color of the car, I will not be painting them green to match the car's exterior paint. This color is only temporary

5....Do any of you have any recommendations as to what brand/products would be best to use? Remember, I will be using either a foam brush, or a rattle-can to do this painting and priming.

Any other advice you can give will be appreciated very much.

Thank you!

[Paul Dobbin]

Jim,

Watch this You Tube video and draw your own conclusions.

I like the POR 15 but prefer the vinegar cleaners. It's a dirty job, but you'll love the results.

[R Walling]

Oven cleaner (yellow label) cleans the frame of grease very well. Wash off with plenty of water, scrape and wire brush, then brush on POR 15.

Wear rubber gloves and a long sleeved shirt or you will find out just how good it sticks and wears. (on your skin)

[nickelroadster]

Certainly rust encapsulators like the mentioned products will certainly be better than nothing but will not be as good as stripping the car down and using a sandblaster. I assume that you don't wish to do this even though it is the best way. The rust converters will eventually turn back into rust but will delay and slow the process. One of the biggest problems you will have is reaching all the frame with the car still on it. I would use Por-15 and just try and cover all I could. I would be more concerned about getting it clean than trying to remove the rust.

[Guest bofusmosby]

Thank you guys for your feed-back and opiions. Believe me, I try to always take everything in, and will consider what those that are more experienced have said (and done). Let me address a few things that were brought up.

AJFord54, after I had made that post about the kerosene, I realized where I went wrong. I bought a can of kerosene a while back to help with the removal of 75+ years of accumulated grease and oil from under the ehgine, and steering linkages. You're right about leaving an oily film. Stupid me on that. I wanted to apply something that will stop the rust best I can, but I also want to give the undersides a good top-coat of paint for protection. I have watched the Eastwood videos, but thought I would ask those that have actually done this, and by your experience, it might save me from making mistakes.

Roger, I have heard and read of the oven cleaner, and I do intend on using some in the near future. I have also read up on the POR 15. Thank you!

Nickelroadster, if I could only accomplish everthing that was "best" to do. I completely agree with you, but for right now, doing it the best way is not an option. I wish it were. One of my concerns is the subject that you touched on, and that is the life-span of the rust encapsulators. I was thinking that by applying a good top-coat, that this would seal the surface, and prevent this from happening. At this time, all the rust is just surface rust, so I would like to keep it from becoming an issue down the road.

Paul, thank you for the video link! You know, I need to give that vinegar a try! Impressive.

One thing that was never discussed, was the paint. What gloss (or lack of) would be correct for my car? Also, what would be a good top-coat of paint to use? Does the metal need to be primed first? If so, what would you suggest?

One more thing that I never touched on was the original undercoating. For example, the underside of the finders there is a grayish colored rough textured coating covering about 50% of the area. I assume that this might have been put for sound-deadening, but also served as an undercoat of sorts. I used my fingernail on the edge of a section, and I was able to remove a small piece. Under this "coating" is what almost looks to be tar, a black like substance. Not just paint because if I look at the small piece that came off with my fingernail, that black layer looks to be pretty thick. What do I do about this stuff? There is some rust bleed-through in some areas, but for the most part, this has protected the metal from rusting. Do I remove this as well? Can I just clean and paint right over this stuff? Is there another thick sound-deadening coating that can be put back on?

Edited July 10, 2013 by bofusmosby (see edit history)

[RivNut]

I've yet to hear of anyone on any of the forums using this rust removal method, but from what I've seen it looks fairly simple, inexpensive, and DIY at home. Watch them in the order I've pasted them so you'll see them in sequence.

Ed

[AJFord54]

I only speak from a 50s+ perspective with regards to gloss vs. flat, etc. and have posted this previously. Krylon in cans works very well and can easily be aimed at the proper spots with minimal masking for overspray. If you do get some on the underside where you don't want it, alcohol will work if you do it quickly before it sets up. A friend of mine uses brake cleaner in place of the alcohol. Don't use laquer, as it will dull anything that you want to protect. Krylon has even come out with a paint that is "all in one", meaning you don't need to prime first. I think I'd still prime where you can on the bare metal, but that's just me.

With regards to gloss paint, I prefer it that way. It is much easier to clean and it will dull a bit with time. Over-restoration is becoming more acceptable, especially in what it appears you are trying to do. However, you might want to contact someone with a car of your vintage and see what they say.

I couldn't agree more with regards to sandblasting being best, but that's a can of worms with regards to accidentally getting it on the body, not to mention the fun of just sandblasting itself. It ends up in your ears, nose, mouth and eyes it seems. Plus, if the humidity is high, it tends to clog up the valve.

Do what you can and enjoy yourself.

[Guest bofusmosby]

Ed, thank you for the video links. The problem with what I want to do is that for the most part, vereything has to stay on the car. Of course, maybe I could dip the entire car for a week. LOL The resulted looked great!

[nickelroadster]

I understand that you are doing what you can and are not going through a total restoration. For my money I would just use Por-15 and not worry about a topcoat as what you are painting is not going to be exposed to the sun. With Por-15 you really just want to concentrate on getting the area as clean as possible. As clean as possible will allow the encapsulators to delay further rust for quite a while. I like Por-15 although it is rather nasty to use but seems to last and it is very hard. The rust converters are a little unpredictable as to how long they last.

[RivNut]

Of course, maybe I could dip the entire car for a week. LOL The resulted looked great!

Perhaps there's an abandoned swimming pool in your area. Drive in - drive out rust removal.

[Guest bofusmosby]

Perhaps there's an abandoned swimming pool in your area. Drive in - drive out rust removal.

That's a great idea!

Nickelroadster, what about the original undercoating/sound deadining coating that is still there? There are places where the rust is bleeding through, and as far as cleaning it, well, it has the texture of the stuff that some put on the insides of boats to prevent slipping. A very rough surface. I've read of spray on coatings that are used for this purpose, but I doubt it would have the same look and texture as what is still there.

[Rusty_OToole]

I use rust paint like Rustoleum or Tremclad, at least 2 coats but 3 is better. Scrape grease and scrub in Gunk degreaser with a parts brush then pressure wash. Scrape and wire brush rust. When using rust paint you do not have to get all the rust off, just loose flakes.

Paint with brush or spray as you prefer. The second and third coats will go on easier.

BE SURE YOU WEAR GOOD EYE PROTECTION. I can't stress this enough. Also long sleeve shirts and a cap.

If you do not have a hoist and are using jack stands or blocks BE SURE THERE IS NO MISTAKE ABOUT IT. Before you go under the car try to push it off the stands. Don't say "he must be crazy I'm not shoving my car off the stands". If you are not sure it is too solid to push off, fix it so it is. You will be scraping, prying and banging around under there and you can't be too careful.

Color is up to you. Semi gloss black would probably be closest to what they used at the factory, or body color on the body. A light color will brighten things up and make it easier to see what you are doing, when you work on the car.

Edited July 10, 2013 by Rusty_OToole (see edit history)

[nickelroadster]

The existing undercoating is a different animal. It is common for this to trap moisture and therefore promote rust. One of the worst thing you can do is to put undercoating over existing rust. Old undercoating should be removed as it essentially just seals in any moisture and accelerates the rust. Yes it is a real pain to do but anything you do over the top of old undercoating would be a waste of time. One of the real advantages to the Por-15 type of product is that the curing process actually absorbs and removes moisture removing any threat from this area. Of course you could promote some oil leaks and go for the British style corrosion protection. Why do you think that everything from Britain leaks oil?

What kind of facilities do you have for working under the car?

[Guest bofusmosby]

What kind of facilities do you have for working under the car?

Jack-stands. As Rusty suggested, anytime I go under the car with the jack-stands, I purposly try to push the car off of them. Don't want to take any chances. Not really sure opf the question. I do not have a pressure washer (that works), and I'll be laying on the garage concrete floor looking up while I'm working. LOL Sorry, I had to say that.

Speaking of the original undercoating, well, not really sure how to remove it. Removing the outer "crust" will expose the tar-like layer against the metal. For the most part, the undercoating has done a good job of preventing rust. I'd say that 95% of where it is is not rusted. There are a few places here and there that you can see some rust bleeding through, but not too bad. I guess I'll have to experiment on how to remove this stuff, without damaging the metal under it.

[RivNut]

I guess I'll have to experiment on how to remove this stuff, without damaging the metal under it.

Nothing beats an Air Needle Scaler for powering off scale, rust, undercoating, and more. For nor more than a hobbyist uses one, they can be found inexpensively at places like Harbor Freight. If you like lying on your back under your car, you can depend on getting dirty.

[Rusty_OToole]

If the bottom is coated with old grease and undercoating you are in luck. Leave the undercoating and paint over it. Unless it is loose and peeling. You may clean off the grease and find perfectly preserved paint or metal underneath.