Thanks for the replies. I think I'll still paint it, but I won't make it a priority.
fwright Steve You cannot seal wood unless you coat it in plastic - all sides. All paint and stains breathe, latex a little more than oil-based. Polyurethane comes the closest to a plastic seal. But anytime you break the seal, the wood attempts to reach equilibrium with the surrounding air as regards to moisture content through the place where the seal was broken. Wood that moisture migrates to/from evenly does not warp. It's the differential moisture content in a piece of wood that causes warping. That's why thin strips don't warp as much as thick wood, and knots and wavy grain warp more than straight grain. In reality, you are not attempting to stop moisture migration in and out of wood. You want to minimize the speed of the change in the moisture content (so that change happens evenly throughout the wood), which is done by retarding the flow of moisture. If your relative humidity (even better measure is dew point) doesn't go to sudden extremes, you should be good once the wood moisture content reaches equilibrium with your room. Painting of any kind does retard the flow of moisture in and out of the wood. things I learned from wooden boats Fred W
Steve
You cannot seal wood unless you coat it in plastic - all sides. All paint and stains breathe, latex a little more than oil-based. Polyurethane comes the closest to a plastic seal. But anytime you break the seal, the wood attempts to reach equilibrium with the surrounding air as regards to moisture content through the place where the seal was broken.
Wood that moisture migrates to/from evenly does not warp. It's the differential moisture content in a piece of wood that causes warping. That's why thin strips don't warp as much as thick wood, and knots and wavy grain warp more than straight grain.
In reality, you are not attempting to stop moisture migration in and out of wood. You want to minimize the speed of the change in the moisture content (so that change happens evenly throughout the wood), which is done by retarding the flow of moisture. If your relative humidity (even better measure is dew point) doesn't go to sudden extremes, you should be good once the wood moisture content reaches equilibrium with your room. Painting of any kind does retard the flow of moisture in and out of the wood.
things I learned from wooden boats
Fred W
Fred's wooden boat experience serves him well. He is absolutely correct. I work for a major paint manufacturer (25+ years) in the technical marketing department. All paints that are readily available to consumers allow moisture to pass through. In fact, it is necessary to do so otherwise the paint film would eventually crack and delaminate. The lone exception to this is swimming pool paint i.e. chlorinated rubber based paint. However, chlorinated rubber paint is not suitable for use on wood.
Painting benchwork is an exercise in feel good. Pop you head into your attic. Are the rafters painted? Look above you in the basement. Are the floor joists and subfloor painted? Vastly more important than moisture control is the employment of good structural geometry, proper construction techniques, and material choice. An engineered truss is a great example. Large spans of heavily snow loaded roof supported with nothing more than spindly 2x4s that have no protection from moisture. Yet the roof doesn't fail from expansion/contraction with humidity change. Proof enough geometry and construction quality is the key, not paint. Use the right materials in the right way and you will have no need for paint other than to make things look pretty.
Alan
Freelancing the LK&O Railroad
You will likely get some things on the bendwork like plaster or other stuff spilled or splattered in the process of building and scenicing the layout. Best save painting the benchwork until later.
Rio Grande. The Action Road - Focus 1977-1983
I agree with Roger. I've never painted any layout benchwork or even a 4X8 sheet of ply for my lst layout. I've lived in N.J. where it snows and freezes in winter and has very high humidity in summer and for the last bunch of years in the Pacific N.W. where it rains and rains and rains.
I've always stacked my wood in the train room criss cross like drying boat lumber or building a campfire and let it air dry and adapt to the room's temp and humidity.
I've had to use Home Depot "white wood" which is pretty crappy and often warped at the store. I've chosen straight pieces and stacked them for about 8 weeks and I've had no problems thereafter. I use 1/2" ply tops and 1X4s for framing and girders. No track expansion/buckling, etc.
No harm in coating everything but it's a lot of work that may not really be necessary if you have the space and time to air dry your lumber.
Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.
Personally, I don't see the point in all this. I have lived near and built railroads near Chesapeake Bay, Hampton Roads, Atlantic Ocean, Gulf of Meico and the Houston *** Channel as well as in many other damp/humid areas. I have never painted any of the benchwork except the fascia. None of these layouts ever had any warping or twisting except one time I didn't install enough crossbraces and the 1/2" plywood had a slight bend in a couple areas. I can't see the time, effort and money to completely seal every piece of wood used to build the layout. I think you're wasting a lot of your resources.
My 2¢,
Roger Huber
Deer Creek Locomotive Works
Steve Hunter Another important issue is the type of paint. Since latex paint "breathes", it would be a rather poor choice for sealing wood. Acrylic paint may be better, but I'm actually leaning toward varnish rather than paint to give a better seal.Steve Hunter
Another important issue is the type of paint. Since latex paint "breathes", it would be a rather poor choice for sealing wood. Acrylic paint may be better, but I'm actually leaning toward varnish rather than paint to give a better seal.Steve Hunter
I would tend to paint the lumber before any cutting is done, and then quickly touch up after cutting/ drilling, before assembly.I have never needed to seal lumber in a layout previously, however my new train room will not be able to have quite as good environmental control as all my previous layouts. The above mentioned procedure is how I intend to approach the sealing issue, to avoid having any exposed areas.Another important issue is the type of paint. Since latex paint "breathes", it would be a rather poor choice for sealing wood. Acrylic paint may be better, but I'm actually leaning toward varnish rather than paint to give a better seal.Any opinions on this?Steve Hunter
We found out the hard way not to use pressure treated wood. It sound like a good idea, but it is not.
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I think it would be best to store the wood, unstacked, for a few weeks in the area where the layout is to be assembled. This will acclimate the lumber, and hopefully any swelling or warping will take place before the layout is built.
I would paint the lumber with Kilz primer before assembly. I think this will be much easier than attempting to paint it when it becomes a 3D jungle of diffcult access.
Believe it or not, I had trouble with benchwork warping even in an interior climate controlles room. Maybe I will prime the benchwork lumber on the next layout, that might be a good investment in time.
-Kevin
Living the dream.
Yes I plan on painting any exposed wood.
I think I'd:
Build benchwork
Paint benchwork (because it's now easier to reach all the spots)(you could even maybe paint some of the parts BEFORE assembly--your call)
Then lay the trackboard
Then paint the trackboard
Lay cork roadbed
Etc.
I'd consider painting the benchwork and trackboard white. The part that faces down will reflect more light. You are painting the bottom of the trackboard, aren't you? This task might be better done after you cut it out but before you attach it.
I think I'd only apply a color coat on the edge of the benchwork (the fascia) and maybe the top of the trackboard. The latter will likely be covered with scenery, anyway; so painting it a color seems unnecessary.
Ed
this is my first post. I'm building an altered version of the rice harbor layout. My layout will be in a garage so I plan on sealing the benchwork. My question is which would work better:
1. Paint benchwork
2. Layout track plan
3. Lay roadbed
4. Drill feeder holes and bus wire holes
5. come back and paint exposed wood
or....
1. Lay track plan
2. Lay cork roadbed
3. Drill feeder wire and bus wire holes
4. Paint everythin or paint everything except cork roadbed
My concerns are:
If I paint the roadbed, will it lose its sound absorbing capability?
Will glued track stick to painted roadbed? Will roadbed stick to painted benchwork?
My goals are to reduce the amount of flexing in the layout due to humidity (I live near Lake Michigan). I bought Kilz primer to seal the wood. It's white and Fleet Farm said they couldn't tint it to an earth color because it needs to be a light color for space in the can. So I'd have to apply a topcoat. What would be a good paint for that? I was going to use an earth color for the subroadbed and a tan color for everything else. What advice can you offer me? Sorry to unload all this at once. Thanks for your help!