Mike Wlez said:
Well, that was short lived…, engine is fine, but the nice blue paint I put on the cylinder covers burned off. I’m thinking I should have used self-etching primer instead of a standard rust-o-leum primer. Any suggestions as to which brand is better?
Try cleaning the covers first, might have had some oil still on it. Make sure the parts being painted are warm as well as the spray paint. I like to put the parts in the oven set at low so the paint can bake on.
Just picked up a can of self-etching primer from O’Reilly’s, I’ll spray the covers down with Brake Clean, and get the rest of the paint and oil off, let them dry real good, and spray them later this afternoon.
Didja get Engine Paint, I think it’s formulated for higher temps.
John
I didn’t, but I would think if I use the right primer, and like Shawn suggested, baking the finish on, I should be okay.
Mike - not if the paint is not rated for the temperature service it is going to be put in. Most paints are not rated for any higher than about 300-400 degrees. Above those temps the paint begins to break down and failure is in the future.
Guess I’ll be looking for a High Temp gloss navy blue then. Water boils around 212 F, I would hope the temp wouldn’t exceed 400 F on the Sammie.
Super high heat header paint:
High Heat Caliper paint:
Anodized blue engine paint:
Various blues including Holden blue if you are feeling like a Road Warrior:
Thanks Todd, while reading the specs on the VHT, it describes curing as baking at 200 F, or “the inherent heat of normal braking operations will also accomplish curing”.
I wonder if the heat from the cylinders count as inherent heat? Temp at the cylinders should be minimum of 212 F. Next time I run her, I’ll have to pull out my digital thermometer and shoot the cylinders.
And that looks like the right shade of blue.
Water boils at 212 F, but steam gets much hotter than that. You need a paint that will withstand at least 350 F, 400 F would be better.
Ah, water in a pressure vessel (under pressure) boils at temperatures above 212f
And boils at lower temp if pressure is less, like about 203 degrees in Denver Co.
Greg
Yep. Or if your space suit springs a leak, the water in your body will boil at body temperature. But that is going kind of counter to the discussion.
Colin Criswell said:
Water boils at 212 F, but steam gets much hotter than that. You need a paint that will withstand at least 350 F, 400 F would be better.
The VHT premium paint is rated at 550 F, and the header paint is rated to 2000 F, so it’ll be fine.
Mike you don’t need the high temp paints. I have used acrylics and regular krylon paints with no issues. That is directly on the boiler.
Mike you don’t need the high temp paints. I have used acrylics and regular krylon paints with no issues.
we heard you the first time before the edit
The high temp paint helps though, espically on anything near the smoke box or cylinders. Some paints, even ones that are not high temp do ok. I believe that RH uses a certain Acrylic automotive style paint in the factory with all finishes baked to cure and harden the paint. I bake my trains in my oven on an old cookie sheet at 180’ F for about an hour or so. You want the bake the paint away from the oils and grease on the steamer. A base etching primer does help and will need to be baked for 1 hour before you apply the finish color. Been painting smaller scale brass model trains for years. Mike
Mike Toney said:
I believe that RH uses a certain Acrylic automotive style paint in the factory with all finishes baked to cure and harden the paint.
I use the same paint system, and there is no need to bake.
Tony - a more fulsome explication would be much appreciated. 
TIA
tac
16mm Association
Ottawa Valley GRS
G1MRA
POCRR
I’m not sure what else to say, other than RH and I have swapped notes on the paint we use, and the paint as supplied does not need to be baked after application.