Asbestos lagging (it is actually only partly asbestos) should be removed
from display locomotives because it absorbs and holds a great deal of water,
which can corrode the boiler and firebox shells badly. This water enters
around upper openings in the jacket and soaks down through. The problem is
usually worst on top of the firebox, and is worst on engines kept in warm,
moist climates. The outer firebox shell on SP 786 (Austin, TX), for
instance, was corroded to less than half its original thickness, requiring
huge sheets of boiler plate (and many, many staybolts) to be replaced so it
could run again. Thus, while asbestos lagging on a locomotive poses a small
threat to nearby humans, it poses a great threat to the boiler, and should
be removed. Encapsulation (which must also be done by a certified
contractor) is only suitable for engines that will be sheltered all the
time. Complete removal of the lagging material is a much better route to
go, so long as the jacket sections are carefully numbered, removed, cleaned
and reinstalled over wood or styrofoam replacement lagging (for
non-operating engines). Before jacket removal the thickness of the old
lagging must first be measured at numerous locations on the boiler and
"mapped", so the replacement "lagging" (actually just a spacer between the
boiler and jacket, which permits air to circulate) can be cut to the proper
thickness. If the jacket is too badly rusted to save, the original pieces
can be used as patterns to cut replacements. Making a new jacket without
those old pieces for patterns is quite difficult, unless one can take
measurements from an indentical engine. The best material for a replacement
jacket is a paintable galvanized steel sheet, such as "Paint-lok".
Should anyone be attempting cosmetic restoration of a locomotive,
incidently, the first step is to take a bezillion close-up photos and make
notes of every detail ---- before disassembly. It's sometimes quite hard to
remember where everything went when you have a pile of parts in front of
you!
Bob Yarger, Editor
Railway Preservation News (website)
www.rypn.org
-----Original Message-----
From: drale99@a... <drale99@a...>
To: BRHSlist@yahoogroups.com <BRHSlist@yahoogroups.com>
Date: Tuesday, March 27, 2001 9:38 AM
Subject: Re: [BRHSlist] Sheridan's 05
>If you're going to seal it up and restore its appearance, why remove the
>asbestos. I would think this would qualify as incapsulation, which could
>probably be done without certified asbastos removal contractors.
>DRale Reeves
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