Greetings! I am new to this discussion board, so a little bit about myself before I ask my question. I am treasurer of Rocky Mountain Rail Society, owner and operator of ex CN 6060, aka "Bullet Nose Betty". We are currently in the process of replacing the boiler insulation on our loco. While we have her stripped down to the bare boiler, we though we might use some sort of rust preventer/inhibitor on her. We have run across an Australian manufactured product by the name of "EXIT-RUST". The literature refers to it as a "rust converter". Using ..."tannic acid in combination with other chemicals,... it converts rust to a stable...strong matrix bonding to the original metal.

Has anyone had any experience with this product or any similar product? What do others use to stabilize/prevent rust on the boiler exterior?

Thanks for listening.

Dale Olson
Rocky Mountain Rail Society

Rocky Mountain Rail Society

Most paints will not tolerate the approx. 400 degrees F boiler temp. On S.P. 2472 (4-6-2), we found that good-quality red oxide oilbase industrial primer cooks off - it crumbles and falls off - as soon as the boiler comes up to temp. High-temp aluminum ("silver" colored) paint, designed specifically for boilers and other high-temp applications, is available from industrial suppliers. This worked well.

A mixture of graphite and linseed oil was traditional on smokeboxes etc. This works fine so long as the engine stays hot. However the graphite is electrically conductive, and not very watertight, so rapidly leads to corrodiong steel when the engine is cold. Our solution was to first coat the area with high-temp aluminum - 2 coats minimum - and then apply the graphite + linseed oil on top of that.

No matter what paint you choose, getting a clean steel surface is essential for good longterm paint adhesion. If anyone finds a high-temp-compatible rust-converting primer, I'd like to hear about it... this would save a lot of time sandblasting and cleaning up afterwards.

doug.w.debs@lmco.com

I do know tannic acid was used as a rust preventative long ago, seems trappers would bury their traps in wet oak leaves to "pickle" them. As long as the product doesn't have any polymer it should do fine... we used ospho, a phosphoric acid product, topped with a couple good coats of barbecue paint on Goat. There are polymer based phosphoric systems such as "rust-reformer", but those would no doubt burn off. The ospho (or tannic acid) pickling will not be affected by temperature.

> Most paints will not tolerate the approx.
> 400 degrees F boiler temp.

This is one of our concerns. Nothing in the product literature addresses the question of extreme heat enviroments. Thanks for your input.

Dale Olson

Rocky Mountain Rail Society