Powder-coat or paint.

[Ianashdown]

I’m planning and budgeting as best I can prior to the arrival of my project car and a question came to mind.

Once the chassis has had everything removed and been sandblasted, repaired as required and stiffened per 26R specs, the question then is powder-coat or paint?

I’ve seen the Eastwood chassis paint that is very close to the original red primer, I think it’s color is close enough and presumably does a sufficient job of protecting the chassis, particularly given that I live in Southern California.

On the other hand, my local powder-coat shop has a powder that gives also a very close color to the original primer and they can do it with a mat, semi-gloss or gloss finish. I’m thinking semi gloss. These guys have done several motorcycle frames and a couple of Formula Ford chassis for me and do an excellent job, carefully masking, plugging holes etc.

So how do we feel about one or the other process? Any pros and cons for either?

Thanks,

Ian

[rgh0]

Personally i prefer to use an inorganic zinc primer and then top coat with a suitable top paint. I used an alkyd enamel. This has lasted for 40+ years on my Elan in Melbourne with a simillar climate to california.

I am not keen on powder coating as I have seen to many poor examples of it flaking off when rust gets under it.

cheers
Rohan

[StressCraxx]

I completely understand Rohan's thoughts about powdercoating the chassis. I have also seen rust spread under powdercoat on Formula Ford chassis. I did some research on corrosion under powdercoating and found that most users simply powdercoated over bare steel. I contacted a coatings expert and he recommended a high zinc primer.

I had my chassis first primed with the high zinc primer and then coated with the semi-gloss red topcoat. It turned out really well. It hasn't hit the road yet, but I have confidence it will hold up well. Our climate is similar to Oceanside here in the Bay Area.

[Ianashdown]

Two interesting perspectives! I first used powder coat on a Triumph motorcycle frame in 1991 and it’s holding up beautifully. Since then all kinds of stands, carts and other shop equipment, 3 sets of wheels and, as I mentioned several motorcycle frames and two Formula Ford frames, all still look great! I had to strip the powder coat from one of the FF frames before re-coating it as the powder coat on there was so tough the sand blaster would hardly touch it! It was that tough!

I asked the guy who runs my local shop about the report of rust under the powder coat. He told me that this was a problem in the early days, but the newer powders don’t have the same issue. However he does say that if too much time passes between sand blasting and applying the powder coat then corrosion can have already started. He requires the parts be powder coated with 2 hours of blasting. Just enough time to mask up and hang the parts.

I have no preference either way, and the desire for originality will probably drive me to painting, but I did want to share my positive experiences with powder coat.

All inputs welcome!

Ian

[alanr]

I would not powder coat anything that is, or could be exposed to getting chipped in any way in the future by road rash or whatever. Once a chip occurs rust will start and travel unseen underneath the powdercoat. You also cannot paint properly over previously applied powdercoat , once it chips it all has to come off.
Powdercoat as far as I am concerned is best left for use on office furniture!

Alan.

[elanfan1]

Have you thought about having it zinc sprayed where they melt a zinc wire and spray the liquid zinc on. Galvanising without the hot dip process. Etch primer then paint with red oxide paint?

[RichardHawkins]

I am not convinced that paint or powder are necessarily superior to one another. I have seen rust creep under paint and powder. What I am convinced about is preparation. Blast cleaning does an excellent job of cleaning and producing a profile for the paint/powder to adhere to. Unfortunately most blast cleaners reuse the blast media, this means that whatever has just been removed from your job and previous jobs is hurled back onto, and contaminating, the surface being cleaned.

When I was working (chemical industry) the engineer responsible for relining vessels insisted on new blast media and 100% supervision by one of his own supervisors whilst blast cleaning was being carried out.

Hope this helps,

Richard Hawkins

[pharriso]

Just to give you another option... Do a search here for POR-15...

Use gloves!! you have been warned

[baileyman]

Before geting my TTR sub-frame, Gary Anderson said, Don't powdercoat it, because a chip will allow rust to start and run under the paint. I thought, That doesn't seem right.

So I've just cleaned up a lift for my barn and scraped away a lot of flaking powdercoat, and you know what? Rust running underneath.

Gary's additional advice was, Prime it, then Rustoleum. A Mark IX tube frame he just painted that way looks marvelous.

[jono]

I had mine blasted with chilled iron grit then finished with zinc rich primer to structural steel specification, then 2 pack.

[Ianashdown]

Just to give you another option... Do a search here for POR-15...

Use gloves!! you have been warned

Hi,

I’m aware of POR-15 and think it’s an excellent product, just limited on color choices.

Ian

[Ianashdown]

Just as an FYI, this is the appearance I’m aiming for.

Ian
SoCal

[mbell]

I guessing the factory hadn't started over coating the red oxide with black paint by the time of your car (S2?)?

If they had a black chassis opens up the options even further.

[2cams70]

Paint is better than powder coat.
I’ve had good success with Eastwood paints in the past. I have tried Por-15 also but wasn’t very successful in the application I used it for and is difficult to apply. Eastwood on the other hand was a traditional style paint but a very good traditional style paint.

[Ianashdown]

I appreciate the feedback. That seems to be the way to go. Did you use a zinc primer before the Eastman paint.

Ian