I'm working on a wood car restoration project, and I'd like to investigate using plastic or composite products as an alternative to traditional milled sheathing. (The car I'm working on is too far gone to save anything so it would be complete replacement regardless) I know Strasburg has had good luck with this method. The car is designed around conventional 3-1/2" x 3/4" milled T&G flooring. Does anyone have any detailed information on the PVC material, like suppliers or manufacturers? Does the PVC need to be supported more frequently or nailed more frequently to reduce heat-induced buckling etc?

Thanks!

Welcome to the interchange.

A quick search on "plastic composite" gives you this:
http://www.rypn.org/forums/viewtopic.php?f=1&t=23036

and this
http://www.rypn.org/forums/viewtopic.php?f=1&t=22251

However I believe the real question is whether an authentic restoration is your project, or a creation of a historic appearing artifact, designed to sit or serve out in the weather with little or no protection. In the reference to Strasburg it should be noted that they are a tourist railroad (with a strong historic bent) rather than a railroad museum.

If you use wood sheathing, most coach builders used poplar T&G that was painted and varnished vs pine as the poplar wood hold the finish and weather better.

If you'd like to go the authentic route, it may be helpful to know that car sheathing was traditionally yellow poplar, and is not a true poplar. It is from the magnolia family, specifically liriodendron. When you order wood, you have to specify liriodentron or you'll probably get a mix of cottonwood, aspen and who knows what.

--Richard

I think you would be far better off using the correct materials and simply maintaining the finished product.

We use Cypress on our narrow gauge boxcar restorations.

It's twice the price of yellow poplar or pine, but it has superb rot resistance and minimal moisture expansion/contraction. This is a real benefit here in the south, where the winter atmosphere is usually very dry and the summer afternoons are navigable by boat.


Matt Bumgarner

I always heard that Cyprus was not good for painting or covering, I was told ( maybe wrongly ) that it will not hold its finish because of the oils in the wood.

So lets talk about Cyprus.

Its easy to find in Texas and fast growing so its a cheap material to get if you are on a tight budget and can go get it and cut it to size yourself.

We've had zero issues with our cypress and are preparing to do our third narrow gauge boxcar with it. We do mill it ourselves with our custom knives, as well as let it dry inside for 3-6 months.

We then apply an oil-based primer (Sherwin Williams A100), sometimes using up to two coats. After that dries, we use the Sherwin Williams "Duration" brand latex paint on top of the primer. This paint is more expensive than most, but has a lifetime warranty.

It does not seem to dry to a hard enamel, but is rather elastic (not tacky). Granted, our cars are indoors and will be under a covered roof, but one car has been painted for the better part of two years and looks as good now as her first day.

Matt Bumgarner

That that is specifically the problem. The traditional Cypress that is acclaimed to have such great decay resistance was all slow growth heartwood; the sapwood of any species has much less decay resistance. Likewise with poplar, if the wood is basically green in color (yellow poplar) or has purple streaks (Magnolia,which used to be graded with poplar) then it is mostly heartwood. But if it's creamy white, it's sapwood, and won't have near as much rot resistance. The problem is compounded by the fact that we can no longer use the wood preservatives that are most effective.

I was under the impression that Douglas Fir was considered one of the best woods for freight car siding, but the siding specifications called for it to be edge sawn, which minimized the wide bands of soft early wood. Douglas Fir porch flooring also used to be edge sawn, and was the correct dimensions (well, OK, it was 3/4" thick rather than 13/16") so it was an easy task to set up a shaper or router table and run the V grooves on the edges. But I haven't tried to buy any in about thirty years, now, and I suspect that what you get at the typical home center is reconstituted toothpicks, not old growth wood. Spotted owls live in fir trees, therefore the material has become unobtainium Only the name remains unchanged.

The other problem is even with good material, the reefer owners typically repainted their cars at least once every ten years. The typical museum doesn't consider the paint dry yet after only ten years.

Old-growth vertical-grain Douglas-fir can still be obtained from quality lumber dealers if one is willing to pay enough. At WRM we purchased a few pieces milled for box car siding a few years ago, it cost about $20 per board.

I am playing the "old grumpy guy", but a museum trained "old grumpy guy"



I have a problem with the use of "restoration project", and "I'd like to investigate using plastic or composite products as an alternative to traditional milled sheathing" in the same statement.

If you are restoring the car, use the best, closest material to the original as possible... Understand the original material, use that understanding to make good choices...

The original r used a high grade of Yellow pine or Poplar, or Redwood which may not be available, or available at a rational cost, but you can make informed decisions about what is not available... and how to work with what is...

Plastic lumber has lots of appropriate uses... I like it for ADA ramps... It holds up well, gives better traction... it needs more support... and isn't by any measure car siding...

I have investigated using glue lams for sills... I am not yet convinced they are the best choice, but am considering them. They are the modern equivalent to wood beams... and they are not generally visible....

Car siding is the most visible material (except paint) and needs to look like the original material... The best route to that is using wood... organic, real wood not the current textured plastic stuff...

The Secretary of Interior's Standards for Historic Preservation might provide a guide on how to make these decisions...

Rant over... never mind... sorry...

eriemp24 please tells us what the car is with as much detail as possible about age, builder, RR, original materials, etc. To what date are you aiming for -- as manufactured condition or some other time. Also what organization do you belong to, if any? What will be the purpose/use of the renovated car?

With that information I think you will get better, more concise, advice.

We own a USRA single-sheathed N&W boxcar. It was restored in the late 1980's to it's M of W configuration. Since then, it has suffered from the usual deterioriation due to outside storage, lack of enough manpower, and very poor quality of the replacement lumber available then and now. The metal in the car is still in good shape, but the wood is very rough, the "new" doors rotted off in a few years. It's a neat and very historic car, but rather low on our priority list unless it gets adopted by an enthusiastic project manager. We have discussed a number of concepts for it's preservation. One of them involves using cement-fiber "Hardie-Plank" siding for the sheathing (this meets most structural preservation guidelines) and having tongue & groove for the doors custom milled out of treated wood. I have a porch railing on my 1926 vintage house that was done by this method by a local millwork company, and so far, it is holding up well.

Yeah, like Marty says, we need more information. I think I read too much into the original post... someone is asking for a plastic substitute for car siding of the ARA standard dimensions for freight car siding, and I just assumed it is a freight car, or caboose, destined to spend its life out in the weather.

I would be the first to advise that if this is a museum restoration that will be stored/displayed in a building, by all means take the time ti identify the original materials, down to the species of the wood, and replace it in kind.

However, if it is a car that has no hope of indoor storage in the immediate future, please don't just go out to the big box store and buy the white wood 1 x 8 material they call "car siding". It's not only the wrong size, it won't last in the weather.

We need to realize that there are some pieces of equipment that are NEVER going to see the inside of a building... pieces like a boxcar displayed outside a grain elevator, its purpose is to be part of a "scene". While the elevator, covered with galvanized metal, may last another fifty years with minimal maintenance, the boxcar won't, and we need a strategy for dealing with this.

By the way, Randy, the Versatex I recommended in one of the older discussions linked to does not have fake wood grain; it is a smooth finish T&G board of the proper width:

http://www.versatex.com/beadboard-products.php

While the product is sold as bead board, please note from the drawing files that the back edges are chamfered, so it will look like car siding if installed that side out.

At the Western Railway Museum a lot of residing work has been done over the last 40 years on both passenger and freight cars. Siding is reproduced as faithfully as possible, so it is safe to say that plastic siding would never be used. On the passenger cars it does not appear that there was ever a standard for the siding, but on freight cars the MCB standard, Plate 20, was usually followed. It provides for T and G siding that has a 3 1/4“ face and is 13/16” thick. The siding is chamfered on the two outside corners.

Siding is different than flooring. On flooring the T and G are not centered, it is laid with the T and G near the subfloor. This was done to give more wear on the wood before wearing through into the grooves. WRM has had cars with so much wear on the floor that the tongs were exposed. Flooring will not have the corners chamfered and is vertical grain (edge sawn) to reduce wear on the wood.

Siding can be either edge sawn or flat sawn. For those woods that are hard to paint, the edge sawn wood holds the paint better. It is also more likely to split when being nailed. Many different woods were used for siding usually depending on what was suitable and locally available to the car builder. Wooden cars wore out quickly. It is unlikely that any wooden car still existing did not have the siding replaced, maybe many times.

Experience is showing that the difference between old growth and second growth woods is significant in strength and rot resistance. I saw a car recently where the replacement poplar siding rotted after ten years of generally covered storage. Old growth wood is still available but expensive. WRM has made excellent use of recycled timbers. A large band saw is used to resaw 100 year old 12” by 12”. The wood is old growth, has tight straight grain, can be resawn to either edge or flat grain as desired, and it is dry all the way through. Whether old or second growth lumber is going to be used, it must be thoroughly dried. This process must be done properly and can take years.

There are several museums considering the use of cypress in place of poplar to try and get a more robust material. It will be years before we know how this works out. Another wood to consider as a poplar replacement is Alaskan yellow cedar. It is a light homogeneous wood similar to popular, but is supposed to have rot resistance like cedar.

The siding should be primed on both sides, both edges, and the end grain prior to installing. Some museums treat the wood with wood preservative prior to priming. The primer should be a really good primer. WRM’s experience has shown that the primers intended for wooden boats works best. When the car gets the finish paint, care must be taken to be sure that the lower end grain gets painted with the finish paint. This is the place the siding is most vulnerable.

In a double sheathed boxcar, there is usually several feet of exterior siding which has the interior side exposed to the interior of the car for a couple of feet below the roof. In a railroad boxcar this backside of the siding would be untreated wood, usually heavily oxidized. I have not come up with a good solution on how to deal with this detail yet. Both brown paint and clear coat have been tried on this exposed interior surface, but neither is like the original.

If the car it to be left outside, proper woods and best quality paints must be used to get a durable car.