Painting the sub frame and similar.
 

The factory uses very durable non-clear coated and flat paint on items like the pulleys and sub frame and sway bar.

I am repainting all this and additional items like the searing column.

Should I use this paint? What type of paint is this? Is it just an industrial black paint? Or should I use another paint? If so what paint?

are you doing any kinda old paint removal? if so I would suggest like a rust inhibiting primer and then just use many many layers of paint. I thought about doing a rubberized undercoating on mine just to minimize the amount of problems later with rust or anything like that.

Since the subframe has allot of welds & panels that tend to surface rust, I used spraycan "paintable rubberized undercoating" and then topped it off with black paint. Note that stuff takes days to dry.

With any solid pieces, chassis black would work fine. You may want to replicate the spay locations mazda put rubber undercoating on.

I use household metal paint, dilued with mineral spirits 50/50 mixture. Also galvanize metal primer. I take out all the surface rust, applied 2 coats of metal primer, then using and air painting gun I paint the subframe.

sandblast the items clean
apply EPOXY primer (best for corrosion protection on bare metal{also use a two part, real stuff, no rattle cans - I know you're better than tha, but thought Id say it})
apply IMHO a single stage urethane paint....can be applied either as a wet on wet over top of the epoxy (best way, IMO) or applied over the epoxy once dried and sanded....

you could go down the line in quality for paints under the car though, an acrylic enamel....or acrylic urethane will get the job done and save you some bucks.......plus all of these paint types will be able to mix a metallic colour.........not many options for pearl however......


edit: forgot to mention....AS FAR AS I KNOW ( never sent away a sample for analysis)....mazda used acrylic urethane based paint on their chassis bits from the factory

Im suprise Aaron cake hasnt chimed in on this yet. I dunno what the factory uses but im going to do as much of the subframe ect as i can with POR-15.

I Mr. cake is always raving about this stuff and i got interested so i ordered the catalog. You can apply it right over rusty areas(or clean ones) and once its dries it is virtually indisctructable. i mean rustproof, chip proof, flexible everything. Its only weakness is UV but that wont be much of an issue for the underbody. Its a little pricey at $100+ a gallon but im just ordering this 6pack they sell to do my subframe/rockers/wheelwells. Its 6 cans, each covering 12 square ft for $38.

isn't 6 cans enough for the whole thing anyway? are they spray cans?

POR-15, i must try this stuff as well, if i ever do a frame-up resto/rebuild i'll coat the underside of my car with POR-15

I agree with the epoxy base followed by the single stage urethane top coat, providing there is no rust. If you want it to last, and not have to do it again in 6 months, use a professional grade paint. A $50 touch gun that you can buy at a home center will do a good enough job for small parts.

I use epoxy as my prime coat for the underbody on all of the 7's I have restored, after sanblasting. That is usually followed by a sprayable truck bed liner. For the parts you listed, the single stage urethane works great. I used it on my widebody 1st gen instead of the usual base/clear. I had stripes on the hood, didn't spray it out right. When I went back a week later to sand it down for a recoat, I had to start with 80 grit paper on my da to cut it. With the normal 2-stage base/clearoat I have used on other jobs, I could start with 320 grit usually, never anything coarser than 220. The only other paint I have found that is as tough and durable as the single stage urethane is Imron, which is an epoxy topcoat.

Why not get it powder coated? You can get flat, satin or gloss black. The stuff is hard to sandblast off.

Expensive and inconvenient unless your setup to do it at home.
Por 15 is only approx 50cents per square foot.

isn't 6 cans enough for the whole thing anyway? are they spray cans?

I cleaned all the rust off, and sprayed it with a metal etching primer, then an epoxy primer, and finally an epoxy spray bomb paint. Epoxy primer isn't tough to find in a spray can, but it can be hard to get color coats in it. I used Krylon's Epoxy Appliance paint. 5 bucks a can and it dries hard as a ROCK. I've knocked it with a hammer a few times without chipping/flaking.

is the POR-15 on a spray can?

The car has no more rust on it I already took that aspect and welded good metal back into the car. POR 15 is being used for the frame rail, underbody, and wells. I highly doubt this is a good canidate for the sub frame brace and stearing column metal pieces and similar items like this.

Powder coating I thought about but driving 2hrs to nearest place and price of it, just is not worth it. With the added tuffness to keep the parts tolerance in good spec.

I aprechiate evrything so far guys. The epoxy methods seem to be being brought up alot. I think I will look into this some more.

And please any more opinions and exsperiance welcome.