Ultimate Chassis Coating Guide!

[joesregalproject]

Okay, I personally feel this is a topic that is not covered very well and has too many opinions associated with it and not enough testimonials and very few verifiable sources. I want this thread to become the Ultimate Chassis Coating Guide. Post what you used to coat your frame and undercarriage, how long it has been there, and how well it has held up. Other useful info might be how difficult it was to apply, where you purchased, and how much it cost you. The only rule is-
MUST BE A FIRSTHAND TESTIMONIAL!
No "My friend did", "My uncle's boyfriend says", or "I heard's". I want people with firsthand experience with these products reporting their results! This thread has the potential to be useful for all of us, and everyone who is still deciding what to use on their build. Help us all out, tell us what you used!

I will start. I used Eastwood's Brush On Rust Converter on my frame and underside of the body, top coated with Rustoleum Gloss Black Brush On paint on my 1987 Regal. The Eastwood's product is applied directly on top of rust, after all the loose scale is knocked away. It goes on white and dries a translucent purple. It has the consistency of milk and it water based. It is advertised to neutralize rust and form a hard paintable surface. My only complaint able the Eastwood's Rust Converter is that it dries to a very rough texture with a lot of fisheyes. My Rustoleum Brush On Gloss Black applied well over the Eastwood's and covered nicely. It was a bit too glossy for my taste and I kind of wish I'd used semi gloss. All in all it came out nice and relatively durable. These products have been on the car for about 12 months and the car has accumulated about 300 miles of mostly dry weather driving, but it has seen rain. It has also been washed with soap and water 3 times. For about 3 months it has been stored in my somewhat damp garage, and still shows no signs of rusting back. As for price, I believe the Eastwood's cost me around $100 for a gallon and I still have probably 3/4ths left. I believe I bought it at a swap meet from an auto body supply place. The Rustoleum was something like $15 a quart from Home Depot and I used between 2 and 3 quarts to do the entire underside of the car, the entire frame, the wheel wells, the rear axle, the floor inside the car, and the firewall.

The only image I currently have is dark but here it is. If I decide to brave the cold garage and take the car cover off I will get some better pictures.

Let's get this thread going!

 

[ssn696]

I have used POR15. It's a 3-step process. Scrape or wire-brush the loose rust off. Degrease with POR Marine Clean (detergent-based cleaner), then use POR Metal Ready - converts rust into a black phosphate. Then coat with POR Rust paint, and finally top-coat with...wait for it...POR Top Coat. It's critical to get all grease and oil off the surface so the rust conversion occurs and the paint adheres. This stuff is expensive, lots of steps, and if you don't use the Top Coat, the rust paint is not only really glossy, it does not survive direct UV light - turns chalky. You have to put the top coat on while the rust paint is not fully cured, or have to sand with 320. You can use regular paint over Top Coat if you sand it lightly. But, I have found on the truck frames I've used it on, you can just about whack the finished surface with a hammer, and the paint does not crack or chip - may be important on a body and frame that flexes. The paint holds up for years. And if you get it on your skin, it's there until your skin wears off - get a box of disposable painting gloves. And spring for a bottle of their thinner. A teaspoon or so added to one of the half-pint cans is needed to spray it and also helps keep the stuff going when brushing and its starting to thicken at the bottom of your paint cup. DO NOT paint right from the can unless you plan to use it all in one day. The brush will convey iron back into the paint and it will harden on you - pour out what you need into a margarine tub or Dixie cup. DO NOT put the lid back on the can without putting some sandwich wrap over it - any stray paint will WELD the lid shut, and the only way you can get any more out is with a church key - and you can't stir it first to get all the solids with it. Oh, and this stuff stinks to high hell. Don't do this in a closed garage that connects to your home. Your wife may seek a divorce. This is what it looks like after two coats of rust-coat and one coat of top coat - still closer to gloss than semi-gloss.

Shifting gears, I have used Eastwood's Rust Encapsulator. It is slightly less work, and unlike POR-15, you can paint over it. Its main agent, the red and black primers, are like marine / oil rig paint. Some rust conversion and bonding. I do like the looks of the Chassis Black topcoat - more uniform and a nicer satin sheen than POR-15 and comes in rattle cans. But this paint requires the same care in degreasing the metal parts to make sure the stuff adheres correctly. Although it looks better, in my experience it's not as tough. It can be scraped off.

I have used Eastwood's frame interior coating paint - it has an 18" flexible wand with a directional nozzle you can fish up into the interior of your frame and try to arrest what has already been damaged. The stuff is really runny and will find every hole and make a puddle on the floor - and your face if you aren't wearing a faceshield or goggles when applying it. But I know of no other amateur applicator / paint that solves the problem of rusting out from the inside on these old-timers we cherish. I'm also using it up inside the wheel arches on some aftermarket bed sides. Eastwood's offers a 2-part epoxy paint, but I have not used it.

Finally, I learned that POR-15 is not a good idea under bedliner. The Line-X guy recommended something called Rust Bullet. It goes on silver and can be topcoated with any automotive paint. It also benefits from thinning, so pick up some some of their brand. Not sure if other types work. It's not been on long enough for me to report back its durability.


If I was going to drive the car in salt - I would go with POR 15. If the car was going to be protected in a garage during the corrosion season, I'd recommend Eastwood's. But I would recommend their frame interior paint.

 

[Clone TIE Pilot]

I used KBS Rust Seal to touch up some parts of the frame and my rear axle. With any of these paint over rust type coatings you have to use their converter first, even if there is not much rust. The converter acts as a prep for the paint, don't use it first than the coating is going to peel off, always use their prep first. So far it is holding up fine under the body.

Up on the body I used aerosol rust converter, then 2K epoxy primer followed by a topcoat.

I have also used VHT rollbar paint, pretty good stuff for a 1K aerosol but takes a week to dry, very slow stuff. If layed down right it is very durable. Used it on my trans crossmember 8 years ago, still holding up. I tried using the VHT on a part of my frame but it kept peeling off, I think the frame has a weird factory coating that it can't stick too, Rustseal has no issuse adhering to the frame. However the VHT adheried fine in the rear wheel wells after I resealed the sheetmetal seams there.

 

[joesregalproject]

Another product that I have experience with painting chassis's is Rustoleum Hammered Finish Paint. I love this stuff. I wish I had used it on my Regal just because it looks better and I believe in the long run it will be more durable (although I have no evidence of this). Rustoleum Hammered Finish paints come in several colors (I believe bronze, silver, dark grey, green and black) and are available in spray cans as well as quart cans to brush on. I have used the black (which is actually more 'gun metal' than black) brush on type on my trailer hitch and outside of the frame on my 1999 Chevy Suburban. This product can be applied directly over rust with no special preparation other than removing loose scale. It adheres to rust much better than it adheres to clean metal actually. It does take a full 48 hours to dry and doesn't 'cure' for about a week. It is a VERY tough finish though. You can smack it with a hammer and it will not chip or crack. The finish is very glossy, metallic, and 'crackled' for the hammered look which covers up the rust well. In my experiences only one coat is required. I have also used the aerosol version in silver on an old craftsman toolbox about 3 years ago and that tool box still looks as good as when I painted it and it gets used just about daily and beaten on. The truck frame was only painted recently so obviously it is still in excellent condition. This paint is available at Home Depot and isn't terribly expensive (I think $10 for the aerosol and $15-20 for the quart). Also works great on wrought iron railings and fences. I've attached an image to show the finish/texture.

P.S. I believe this used to be sold under the brand name "Hammerite".