Many, if not most, steam locomotive cabs were lined with wood planking. I'm guessing this was to reduce noise and act as a form of insulation. Can anyone offer more insight into wood cab lining, and in particular, which woods were the preferred types?

Dick, I've seen and used mostly pine and similar softwoods, but that may have a lot to do with the places I've worked rather than anything else - it was inexpensive and plentiful. I've never seen furniture quality hardwoods used, although it would be beautiful...... for a while at least. It does provide some acoustic as well as thermal insulating properties.

Traditional cab lining was tongue & groove bead board pine or poplar, fairly narrow "boards". Usually painted in a medium or dark green. The dead air space between the wood lining and the cab steel was supposed to act as insulation space.

Unless you are operating 470 in dead of winter, restoring/replicating the wood lining should be just fine, and make the cab look the way it should.

A later variant was sprayed-on "Insul-mat", basically looks like auto undercoating, sprayed right onto the back side of the cab steel. NKP went in for this stuff on the later Berkshires.

Howard P.

Howard and Dave, it's actually an academic question, rather than a direct application to 470. We're not nearly at that point and probably won't be until mid 2017. The cab restoration will probably be an "in-house" job, as the worst steel is around the floor - well, there is no floor- and it can be cut out and replaced. Plenty of missing pieces though!

The question about wood had to do with an inquiry from a heritage carpenter who asked me. Pine, or other soft wood would be cheap and abundant, but oak less likely to burn and last longer. I know green was the generally used color, but why green?

So much to learn!

I've seen green, gray, brown and cream.

They all turn pretty much black over time!

Keith

If you don't use tongue and groove, the creaking and squeaking when the locomotive moves will drive cab occupants nuts.

For a working locomotive, or one that will be stored outdoors, line the cab with fiberglass insulation before applying the T&G lining. This helps keep the T&G wood cooler in the summer. It will last longer if it doesn't get cooked every summer by a hot black steel cab. We did this on S.P. 2472 and are pleased with the results.

- Doug Debs

Burning isn't really an issue. If you've got enough flames on the cab roof that are hot enough to ignite wood, you have serious problems. It is possible to have a flashback on an oil burner, and I have seen one that rolled up and across the cab roof, but it only lasted a moment and wasn't very hot. It didn't even damage the paint. (Though my eyebrows were missing when it was over.)

Soft wood was probably easier to cut and fit, as well being available.

Modern poplar is not worth trying to use. I'd stick with a fairly fine grained SPF with small knots only, cut to about 2.5" plane to a half inch then mill the T&G and a bead to be fancy about it, chamfered if you really want it to look nice.

Modern poplar is probably alright. It is a medium hardwood which will take a little more abuse than pine. Poplar however likes to move around when it gets wet. If it is fastened on shorter centers it will be alright. Douglas fir would be another good choice however the soft woods are very expensive. In grading, clear pine will be the best. Select pine will have some tight knots. Any other lesser grades will have open and larger knots. Any knots will have to be sealed with shellac before painting. primer the back sides before installation.

Unless the roof is completely sealed from water leaks then do not insulate. Any insulation which gets wet will hold water which in turn will warp and rot the wood.

If the budget will handle it I would find a mill that has stickering machines to make moldings. That would be for some of the complicated profiles. Simple lap or t&g can be handled with a table saw and a router table.

I am assuming that this discussion is for a steel cab... I know Debs' project was...

Traditional wooden cabs were stile and rail and panel construction. In these cases the interior of the cab was just the back side of the exterior material.

In the 19th century, Baldwin commonly used walnut for cabs to be varnished, and ash if the cab was to be painted.

Recently several of us have found evidence that some early locomotives had cabs which were painted, then faux grained (specifically Central Pacific "Jupiter")

Randy

1 by 4 (measures .75 by 3.5 inch) Southern pine V grove car siding was used in most of the original cab and caboose interiors I looked at.
You can mill the edge V grove on a table saw from T n G flooring or buy it.
One source I found online under classic yellow pine ceiling.

http://www.southernwoodspecialties.com/ ... iling.html

Clear pine was more available back in the day. You will probablely have to weed out "C" grade if you want clear.

The one 19th-century wooden cab I've been able to get a close look at recently is on WW&F No. 9 (SR&RL No. 6), which was built by the Portland Company in 1891. It has white oak stiles and rails and tulip poplar panels, and was intended to be painted.

Knowing Baldwin practice I had assumed the stiles and rails were ash when I first saw them stripped down to bare wood (the two species have a similar grain figure), but Marcel Levesque happily corrected me. I took a closer look and sure enough, they were white oak. (Marcel led the restoration of the cab, and his day job happens to be restoring antique furniture, so of course he knew what he was talking about.)

This choice of wood is surprising to me, at least for a Maine-built locomotive, because ash is rather more common in Maine's forests than white oak, and tulip poplar doesn't even grow north of Massachusetts (except for three small populations in Vermont), and I would expect Portland to have preferred local woods. (In contrast, both white ash and black walnut grow abundantly in southeast Pennsylvania, so their use by Baldwin makes geographic sense at least.) The only explanation I can think of is that white oak is used a lot in shipbuilding, and the Portland Company actually handled more marine work than railroad equipment, so perhaps they had already had a supply on hand.

-Philip Marshall (PhD in forest ecology, so I can't help but think in these terms)

Looking through the Library of congress pix for cab interiors and found this gem by our ol' buddy Jack Delano.

http://cdn.loc.gov/service/pnp/fsac/1a3 ... 34607v.jpg

From the CNW 40th St shops in 1942.