Model Railroading > Drywall vs. plywood sub-roadbed material

Ok, I've heard that people are using drywall board instead of plywood for the sub-roadbed base. I did a search in TO, but didn't find much. Opinions, thoughts, philosophical discussion? 

I'm at that point of building the layout and man, that plywood cost is outrageous. Just looking at a possibility of saving some money. At least for the flat parts of the layout. 

Thank you for the information. 

Mike ONeill
Parker, CO

   My 2 cents worth is I wouldn't use sheetrock.  It would be easy to punch a hole in it. Sheetrock belongs on a wall...


  Steve H...



Edited 1 time(s). Last edit at 08/14/18 08:58 by hartrick24.

In my never humble opinion, gypsum board is too heavy, too brittle and too hard to work with. My suggestion is to bite the bullet and buy the plywood. You'll be happier in the longrun. That's what I did.
Bill Pyper
Salem, Oregon
 

Buy the plywood. It's not like you need nice interior grade. Good old nasty exterior grade will work just fine.

Never heard of using drywall. Not strong enough.

As with any civil engineering project, it’s always best to put some money into the sub-base. It’s true for track, it’s true for bridges and it’s true for model railroads.

I can think of two major drawbacks for drywall: the dust created when cutting and trimming and its tendency to warp under a load when laid flat.

Posted from iPhone

Read about some folks in the Wisonsin area trying it out. Not sure if it was only the roadbed, or on top of plywood or the whole subsurface. I beleive they were looking for something that did not expand or shrink with temperature.

I think the 2 inch foam being used in some of the modern layouts would be the way to go. Plywood for yards and multi-track areas but just the foam for most the layout.

Another approach is to use a spline made from vertical strips of particle board glued together. There's a number of methods to that as well.



Edited 1 time(s). Last edit at 08/14/18 09:38 by TCnR.

I am part of that group using drywall-and it's spread beyond here to a few of the operating railroads that were on display in KC and was an article in MR I think.. Some things you may want to know about it. We use 5/8" drywall and put it over benchwork grid boxes built out of Baltic birch plywood rather than dimensional lumber (tend to be straighter, less warping). 1/2 inch 8 ply is preferred, ripped into strips on a table saw makes it economical. Grids are on 16" centers or smaller so sag is kept to the minimum. You can cookie cutter drywall, but we don't without more support. We don't walk on our benchwork either, though I have crawled on it. Many of our layouts are double decked so the thickness of that plywood grid can vary from 1 and 1/2 inches on top to a base of 2 or 2.5 inches. We even make helixes out of it as sub roadbed. Very few climates get as much temp variation as we do. Humidity as well. it's used on 10 operating layouts here in our Riverrail operating group-which you can see on Facebook (https://www.facebook.com/profile.php?id=1533806023558029) or at Riverrail.com. Some articles coming in RMC soon as well. My new layout (the 3rd) I'm just starting will use it as well.

Your mileage may vary, but it works for us!

Dave Burman
modeling the modern Twin Cities
Trempealeau, WI



Edited 1 time(s). Last edit at 08/13/18 18:09 by bnsftcdiv.

DO NOT skimp on roadbed because of money. If you don't have the cash to do it right the first time, where will you get the time and money to do it right the second time. Do like i am, just deal with putting off the start date and buy a sheet or two a month until you have enough to jump in. You don't want to have roller coaster track or other track issues at a later date. I've seen some fine railroads that operate so poorly that it takes the fun out. Stride for prefect track work from the beginning, it pays off in the end.

Most people wind up doing what they want. And learn the hard way.  I built my last layout a few years ago when like now plywood prices were pretty steep.  So 1/2" OSB was a lot more inexpensive. One side is very smooth..almost glaze like..the other with a slight texture. I braced accordingling using screws and construction adhesive to fasten it down. The only issue I noted was that the ends (not the sides) had a slight puffyness that needed to be trimmed off or sanded down. I have no expansion or contraction issues here in the PNW.
The cork roadbed is glued also with contact cement and no I dont plan to salvage anything when "that" day comes around.
RB 

Laminated spline makes a good roadbed except in yards.

Personally...I use plywood. But I know several guys in KC who have used drywall with little ill effects. Drywall is dimensionally stable, cheap and dead flat.

I’ve had my fair share of expansion/contraction issues with my 3/4” cabinet grade birch plywood. It’s stable now, but those first couple years were brutal!!!

MOAR

Posted from iPhone

God help you if the wallboard gets wet.  It sags, expands, not a pretty thing.

The dust from just cutting and even just handling drywall is insane.  We just demolished a couple of walls to prep the layout room, and I am very glad we put up plastic sheeting to prevent the dust from getting all over the room.  Wear a respirator. It helps.

Cheers,
Harry

I would vote for plywood. Would have concern with moisture contamination with drywall.

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I am building the 2018 PC out of wood framing-supported 2" foam, and would never switch.....a good solid surfece that is easy to work with, and is almost universally straight and flat.  

Sheet rock would not take water-based adhesives well and would be a pain at scenery time.  About 20 years a go a manufacturer tried to adapt sgheet rock to maritime joiner systems and it falied miserably - it hates humidity.  The only plus I see is the ability to create a smooth surface over a very large area, but I can do that with foam as well. 

It is not very strong in bending.

Bob

I'm an old timer when it comes to laying track - still like using plywood as a sub roadbed & homasote as my roadbed.  The sound damping qualities & spike holding ability of Homasote is un-surpassed in my opinion.  I  belong to a club & we built the large layout this way with hand laid track & it is still rock solid after 30 years.

I concur. This is the way to go. I'd like to also add to seal the homasote with paint before laying track. Temperature / humidity control is huge as well for the bench work and rail joint gaps.

jburek Wrote:
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> I'm an old timer when it comes to laying track -
> still like using plywood as a sub roadbed &
> homasote as my roadbed.  The sound damping
> qualities & spike holding ability of Homasote is
> un-surpassed in my opinion.  I  belong to a club
> & we built the large layout this way with hand
> laid track & it is still rock solid after 30
> years.