Boiler Painting - Coal Fired - Midland Red

[Hope Mountain Railway]

Can anyone advise me from their experiences? I'm currently renovating 'Rajim' and old Mike Gaskin Coal Fired loco from the 1980ies. Have taken off several layers of paint from the boiler. Top was black, then the light green that it was most photographed wearing, and then the original dull red. Not sure what these paints were - but all were applied directly to the boiler and firebox, and all have stood the test of time. I've made a piece of cladding sheet for the main boiler barrel out of 0.3mm brass sheet. Can anyone advise me of any modern 'non black' paint that will work successfully, particularly on the sides of the firebox. Current thinking seems to be that modern acrylics are too soft. Any help appreciated. Thanks, Gareth

[Keith S]

Some auto parts stores carry "exhaust paint" and "brake caliper paint" that is meant to be heat tolerant. It comes in a limited selection of colours, like blue and red, I think.

[GTB]

Current thinking seems to be that modern acrylics are too soft.

Depends on the acrylic. Roundhouse use a two pack acrylic, which seems adequately hard.

I use ordinary alkyd enamel over etch primer on brass boiler cleading without any problems at 40psi boiler temperatures. I use an industrial spray enamel, but Humbrol, or Precision Paints, would do the job.

What sort of firebox is this? dry backhead types will get a lot hotter around the firebox than boiler designs with a water leg, or balanced flue type gas boilers.

I paint my gas fired boilers with black pot belly stove paint and insulate the boiler cleading with a thin layer of wool felt, which keeps the cleading cool enough to touch on gas fired boilers. No practical experience of coal fired boilers in this scale though, or externally fired ones for that matter.

For what it's worth, on the 12" gauge loco with a coal fired Brigg's boiler (a dry backhead type), the firebox cleading is insulated with 1/4" of kaowool and painted with cream epoxy enamel from the local hardware. The cab floorboards aren't insulated from the backhead and start to smoke if the fireman gets too enthusiastic, but the cleading paint is showing little sign of scorching.

There are heat resistant paints available for car motors in the local speed shop, but the colour range is limited and the choices are a bit bright. Some industrial paint suppliers may be prepared to mix a custom colour in a heat resistant paint, but what you'd do with the rest of the 4 litr tin, I've no idea......

Regards,
Graeme

[JMORG]

Usually 2-pack will surfice, Garages use 2-pack when painting cars, so if you ask them I'm sure they'll be happy!
Smokebox and other matt black items can be painted with bbq paint...

[GardenSteamer]

I have used Precision Paints enamel and this doesn't seem effected by the heat, even on a dry backhead.

Immediately after spraying I put the component in an electric oven at 100 deg C for an hour. This stoves the paint to a very hard finish