I'm considering using high temp engine paint on a zinc galvanized frame (CMA type) instead of powder coating. I know a few people out there have taken a similar approach... just wondering how it worked out and if anyone would recommend against it.

No reason you cannot use a rattle can of paint. Getting a nice even polished finish may be difficult but if it is an internal frame and will never be seen once the body is on it is not that big of a deal. For an exposed frame my personal recommendation would be getting it powder coated or take it to an auto shop and have them spray it for a nice even finish.

I second the go-ahead. I spraypainted my S-20's frame, first with rust-inhibiting primer, then a couple of coats of rust resistant paint. On my machine, there is really only one place where the frame is visible under the bolt-on body panels so it wasn't hard to get an even coat and a nicely finished machine. I will be the first to admit it doesn't look nearly as nice as powder coating but for $10 you can't go wrong. On critical areas, make sure you keep the sprayhead at least 6" from the surface and start the spray when the can is pointed beside the workpiece, then move over it. This will allow all the collected larger droplets to be sprayed beside the machine rather than on it, leaving you to deposit only the more evenly sized particles onto the frame.

I have powder coated frames in the past but I have not been able to source a cost effective shop that also does media blasting for small pieces. I think in some cases its worth the expense, but for this machine I'm just looking to clean it up a bit. Its not visible once the case is on anyways.

I've sourced an engine paint that recommends you cure it at 300F for 2hrs after spraying to achieve optimal hardness. This seems interesting so I think i'll give it a go.

What about an epoxy enamel?

When I restored my Jr., first I sand blasted the frame then found a body car shop who sprayed a rust-inhibiting primer and a thick coat of paint dried in oven.
The finished paint was sometime too thick, I had to pay attention during assembly to not chip it.
Almost 2 years ago payed 60 euro for sand blasting and 70 euro for frame amend (due to deep rust) and paint.





Pierluigi

Depending on the finish you require you could use VHT Wrinkle Plus or VHT Engine Enamel

No need for primer - just sandblast, paint, put in the oven.

Loads of info on application and curing but mostly on car forums.

I was thinking of doing my Kathy in a nice red wrinkle

James, I just finished a restoration and I used VHT engine enamel rated at 500 degrees. It turned out pretty nice with a gun metal and a clear coat. 3/4 of the way down this page is a close up: Pasquini Livietta restoration for first timer
I had a couple of issues. The first was some running on vertical pieces. The second was I didn't remove all of the paint and some of it started flaking through the enamel during baking. Not sure why this happened but if I were to use this method again (which I think I would, although I have only been using this machine for a couple weeks so I'm still monitoring prolonged durability... I'll get back to you in 5 years It feels like it will be good though and has not chipped on the few inevitable bumps it has taken upon reassembly) but I would do some things different. PATIENCE. More time spent removing paint, a primer would be used, more even and light coats. Also the baking can't be good for you. I got slightly light headed from the fumes. But it's a relatively cheap method, so use your savings on time and care to apply it well and it will treat you well. The worst thing that happens is you are out $20 and a poor finish and you go ahead with sand blasting and powder coating or similar.

Thanks for the advice everyone. I went ahead with a few test pieces using a similar product to the VHT called Duplicolor, also for high heat engines. http://www.duplicolor.com/products/enginePaint/

I stripped down to bare metal and started light. After baking at 300F for hrs, the finish was very hard and I was pleased. I started with the low-gloss black but have sinced decided to go to the gloss finish since to hopefully make it a bit easier to keep clean. I'll use the matte as a base coat.

I'll report back with some photos.

Before:


After matte "primer" coat: