The last 2 arch-brick replacement projects I was involled in (99, 03) the size/shape/rating were and still are off-the-shelf items from most refractory suppliers.
These are standard high temp materials with no asbestos

"T"

Since firebrick is hydroscopic, good conservation practice would be to not replace it, but to remove the existing brick entirely and clean the firebox, perhaps with a rust conversion treatment after.

dave

Thanks Dave.
That was going to be my next question as to what to do as far as interior of firebox goes. There is some surface rust and slight water staining bu no major rust flakes or problems.

Pur-15 is used by race car builders. Even the newest piece of metal has some rust, minute but still there. This paint attacks existing rust and protects against future rust. Expensive but you only use it once and it works.

Thanks! I will add it to the list of products to find. Has anyone else had experience with rust treatment in the firebox?

POR-15 is used by car restorers, and can be painted over top of exsisting rust

I use a product called OSPHO. Converts the surface rust to a neutral material and requires no additional coating, although you can paint over it. I'd certainly use it on the entire boiler shell before installing new spacers and jacket, as well as a base coat on any rusty metal you plan to paint.

dave

Thanks Dave.
Will have a look round the local dealers here to see what would be best to use in case the products mentioned are unavailable.

Howdy,

I have worked with both por-15 and a product called rust-bullet and can say that both products work well. These paints are actually more of a moisture catalyzed resin than paint from what I understand. Someone with more chemistry background could perhaps chime in on this one. Either way, both paints are VERY durable (almost powder coat scratch resistance), easy to apply via brush, and require little to no surface preparation. I have no commercial interest in these products although I will disclose that the folks at rust bullet were kind enough to provide enough of their product to paint the exterior of the boiler on my locomotive (45 ton porter) and has been holding up quite well to sun and rain exposure as well as abrasion. I have used POR-15 on a Plymouth AL gasoline mechanical locomotive and was also very pleased with the results. Best of luck with your project.

Stathi

Thank you for the reply Salty. That is great to know there is no concern over asbestos with the firebrick then.