hi,
i’ve seen several posts here about what type of covering for laying track on and haven’t seen anyone mention the use of drywall. i would use plywood under it though. seems to me it would be easy to use. maybe firm enought for track nails and securing buildings, scenery and easy to cut for under and overpasses and rivers. probably use a good sealer and lay the track. easily paintable. any thoughts on this type of material?
thanks,
michael in texas ‘EssPee for me’
I use plaster wall board (“drywall” or “sheetrock”) over plywood on the large flat areas of my layout (like in yards). Then I laid the track right on the drywall, and it works great. My layout is going on 15 years old and the drywall areas backed by plywood have not given me any problems.
Before doing this I spoke with an architect who was also a model railroader, and explained that rather than using homosote for these large flat areas over plywood, I would prefer to use plaster wallboard, since it was far cheaper and easy to find.
He replied that in terms of the effects of moisture from scenery work, ballasting, and the like, plaster wallboard should actually be more dimensionally stable than homasote, which has a tendency to swell if soaked with moisture. Plaster wallboard will have problems if immersed in water for a long period of time since it will tend to crumble. But when considering short-term moisture from typical model railroad construction – plaster wall board is actually a better choice for large flat areas.
So I went ahead and haven’t regretted it one bit. Since I use masonite spline for my normal roadbed and I glue the flex track straight to the spline with gray latex caulk, I have no use for homasote. IMO, the stuff is over priced and over hyped in the hobby, when there are often better and cheaper materials out there. [swg]
If Joe says it works, it works. I used extruded foam and it also works, and seems easier to me. You can cut foam without all the dust. You can carve small scenes in the foam like ditches and small lakes, much easier than drywall.
Joe:
How did you fasten the tracks to the drywall, glue (caulking) or nails?. The advantage of Homosote over cork is that spikes and nails driven into homosote do not come up like they would in cork. I would suspect that this would also be true of sheetrock unless the nails were driven through into the plywood below.
[:O][:O][:O]
Ya really made my eyes pop open with that post, Joe!
I woulda thought the water and alcohol floods used in scenery construction (to say nothing of the drywall sucking moisture out of plaster landforms and what-not before the plaster has a chance to set) would make it a very UNsuitable material. Did you prime the drywall before working on the surface? Or does it not matter?
I must admit suprise. Though on thinking about it, drywall can certainly handle short term moisture, joint compound isn’t that much different to what we do with it. I don’t think it would take a nail for anything, I think I’d glue it down and never drive anything through it, since as soon as you do you’ve got to fix the dimple. But an interesting thought…
I would think that drywall would be a bit heavier too. I suppose it depends upon how large the areas are.
For my current layout I’m using plywood covered by styrofoam sheets which are themselves covered with drywall joint compound. So far I have no complaints. I didn’t even think about using sheetrock. Maybe an idea to keep in mind for the next major layout build.
I have seen several layouts in the Wisconsin area that used layers of drywall for the roadbed, with no plywood under it. They don’t seem to have any problems with it. I still don’t think I will give up my plywood and homasote. Dave H.
Nope, didn’t paint it ahead of time, and fastened it down to the plywood with good old short stubby drywall screws (about 3/4" preferred, just enough to grab a bit in the plywood if sunk down in well below the surface of the 1/2" wallboard. I spaced the screws about a foot apart.
I glue my track to the wallboard just like I do everywhere else, gray latex caulk.
You can even carve the wallboard a bit, for some simple ditches, etc, although it doesn’t carve as easy as homasote or other soft fiber board. Wallboard is also heavier than homasote, 'tis true.
But the moisture thing during ballasting and scenery work has never been a problem … but if that worries you, use green board (the special plaster wallboard they use in bathrooms behind showers and tubs). Green board is also easy to find at your local Home Depot or Lowes. [swg]
I’d worry about sagging over the years … I’d recommend at least backing it with something stiffer like some plywood.
I would like to recommend that if you go the drywall route as Joe has used successfully for 15 years, that you may consider using the more waterproof version “greenboard”. It may be a bit more expensive, but it is almost impervious to water. Don’t be fooled into thinking that the blueboard version is waterproof, the paper coating is only water resistant to withstand the moisture of the plaster skimcoat until dry.
Greenboard not only resists prolonged waster contact, the treated gypsum core is substantially stronger and doesn’t crumble or deteriorate like it’s counterparts.