Lagging

Lagging is insulation applied to the boiler, cylinders and steam lies to retain heat. The jacket is a thin metal covering over the lagging to hold it in place and provide improved appearance of the locomotive.

Lagging

Fiberglass

Fiberfrax

• Fiberfrax
  • A new material made from washed ceramic fibers with binders added to form a lightweight, flexible asbestos-free insulation. Withstands temperatures to 2300 F. Excellent for aircraft firewalls. Available in 24" wide. Sold by the foot.

• High Temp Coating
  • Used as a hi temp coating over Fiberfrax, or other pourus materials. Can also be used as an adhesive to bond Fiberfrax or other pourus material together.

• Jonathan Hollahan writes on live_steamer@yahoo.com:
  • I used two layers of 1/8". The stuff is fairly fragile, tears easily, and doesn't like masking tape. I used stainless steel wire to hold it in place until the jacket was installed.

Asbestos

Asbestos was commonly used on model steam locomotives constructed prior to the 1970's when the extreme danger of the material was discovered. DO NOT use asbestos on new builds. If you work on an older steam locomotive take the necessary steps required for asbestos abatement.

Air

• crew writes:
  • I do have an air gap between the boiler shell and the jacket and it does not get so hot that burns you. Yes it is hot but i can touch it with out damaging my skin. 20 gauge steel works well, I did not paint the inside. and I don't have a rust problem after ten years. This could be because of the air gap.

Jacket

Steel

• crew writes:
  • I am using 20 gauge steel on my American, the jacket is now 10 years old. I did not lag the boiler as I did not like the idea of it not allowing water to freely run off and dry form the heat of the boiler or air. I do have an air gap between the boiler shell and the jacket and it does not get so hot that burns you. Yes it is hot but i can touch it with out damaging my skin. 20 gauge steel works well, I did not paint the inside. and I don't have a rust problem after ten years. This could be because of the air gap.

Galvanized Steel

• GWRdriver writes:
  • Galvanized steel has a naturally "oily" surface and the old way of prepping galvanized material (like gutters) is to first to scrub it well with hot detergent and rinse. Then etch it with household vinegar, apply until it acquires a frosty patina. Kill the etch off with a soda water (or baking soda) and rinse well. I then use one coat of automotive self-etch primer, then paint of choice.

• RichD wrote:
  • I owned an engine with a galv duct metal jacket that would not retain it's paint after two attempts. Stripping and coating with zinc chromate (now zinc phosphate) primer then top color coat and now over ten years old is still like new.

Blued Stove Pipe

• Lovesthedrive writes:
  • You might consider going to a stove shop. Some of them still sell blued pipe.

• Charles Pipes writes:
  • Another advantage to this is that you can ask for a heavier gauge piece of steel than the pipe would normally come in. I used a shop here in Huntsville to roll 18 gauge sheets for a small beer keg furnace. When they found out what I needed it for they even spot welded my seam at no extra charge. Another plus if you lay out your whole pattern on paper you can transfer prior to having them roll it.