Replies

1. 
   OneofmanyBobs | Aug 23, 2004 01:08am | #1

   Poplar is one of the worst woods for exterior use.  Very prone to rot.  Yes, I know you said it would be under cover.  I still would not use it.  Too soft.  Marine plywood or die board is better.  However, if you want something that looks like metal, use metal.  The folks who built the car used metal for good reason. 

2. 
   301 | Aug 23, 2004 01:49am | #2

   I would consider African Mahogany.  The railroads used Mahogany alomost exclusively for decades.  I do some work on old railroad cars and the condition of 100 year old mahogany is fantastic.  With proper care and installation/finishing it will give good long service in difficult environments.  The African variety has almost the same properties as Honduran or Cuban but it is very affordable. 

   Cherry might be another good alternative, it is more durable then you think.  Additionally some trolleys were constructed with cherry window sashes and so fourth and have held up pretty well. 

1. 
   Patto | Aug 23, 2004 02:04am | #3

   I did a subframe for an MG TF (1954) a few years ago. On that car the chasis is steel, but the body consists of a wooden frame coach bolted and screwed together ( a few 1/2 joints) or screwed to the steel. The skin is then nailed to the body and painted.

   In my research for this the originals (English) were ash. I made mine from Tasmanian Oak (a eucalypt) and I know that oiled it was still completely sound after 10 years when I sold the car. it did not spend all of its time under cover and had two years in the tropics.

   However, at the time I started, there was a full-time coach builder doing this for a Rolls Royce restoration company in Melbourne. He was a pattern maker by trade and made an initial from anthing he could that worked, often jelutong. His finals were in african mahogany as suggested. All of the cars I have seen framed in this manner have been done from solid timber cut to shape. There is sometimes some bending, for example over the roof.

   My lesson was that if you are going to have to do things like hang doors, make a pattern first.

3. 
   Alan | Aug 23, 2004 02:18am | #4

   EADAMS15,

   The others are right that a harder wood is better than poplar (the originals I've seen have all been white oak).  But by using the materials you mention poplar will work--if still something less than ideal.

   Seasonal movement can be halted by completely encapsulating the wood in a material that is impermeable to water.  Epoxy is perfect for your purposes.  I've used it extensively for things like yours, and it has never failed.

   You would have to be very careful that each and every tiniest little bit of wood is covered with epoxy.  When I was making and selling plans for tonneau covers for pick-up trucks I pre-coated all the wood with epoxy before assembly.  Wherever I had to pierce the wood, to put in a screw for example, I would use various techniques to be sure there would be no bare wood.

   I fiberglassed my tonneau covers using epoxy as the resin.  Even 4oz fiberglass cloth significantly enhances wood's resistance to abrasion, denting, and so on:  i.e., fiberglass makes softwood more like a hardwood.  A few coats of paint, spar varnish, or any varnish with UV inhibitors, makes it bullet-proof.

   If you want to further consider this method, go down to your library and see if they have The Gougeon Brothers on Boat Construction.  The brothers make all the WEST System epoxy materials and have long been the experts on epoxy/wood use.  Their book is worth a read even if you have no plans to ever use epoxy.  Their work is gorgeous and the book conveys many of the design and construction details of how their work got that way.

   Alan

1. 
   Adam13 | Aug 24, 2004 04:07am | #5

   Thanks to all for your help. A year ago I had an opportunity to talk to a man by the name of Charles Wacker who was third generation owner of a truck body factory in Philadelphia. He said that in the first third of the 20th century they used poplar very frequently as the clading of box bodies - moving vans, delivery trucks, etc.. The owners just may have more interested in weight savings than longevity. Anyway, that's where I got the idea. I'll be giving a lot of consideration to each of your suggestions, thanks.

1. 
   301 | Aug 24, 2004 08:15am | #6

   I mentioned railroad cars in a previous post;  many railroad cars did utilize poplar but always in areas where they were "out of the weather".  Case in point, Canadian built parlor cars on the CN.  They used poplar for under flooring (three layers with tar paper and wet paint layed down between) and roof carlins.  Both of these applications mattered not if there was some "movement" and were protected from the elements.  I think truck trailers would be a similar application as are out of the direct weather.

   I would recommend you seek out a historical group or some other resource to get a "for sure" answer.  That is what we do with railroad cars, if you know where to look you can often find the original order forms from the car factories that tell us exacty what to do.  Your freind's Autocar seems too important a project to make a historical error on.  I bet there is an on-line community of old truck restorers that can point you in the right direction.  Sounds like a fun project!