PLywood or Foam?

[SAL Comet]

Ha Guys, I'm headed out to get some 1x material and plywood for my attic layout. I 'll have 4 sections that are 1'x8' and two corners 1'x4'x3'. Sinse the sections are so narrow, I was thinking of using 3/8" plywood. I also cosidered using the thick foam instead, however it's not readily availible here in the South, all they sell is 1/2". What do you guys think?

 

[Fred_M]

1/2 inch foam isn't really strong enough on its own, even in a frame. I would go plywood with the foam on top, or plywood with whatever on top if all's you can get is 1/2 foam. Fred

 

[Papa Bear]

SAL, I've run into the same problem. You can laminate layers of the 1/2" foam together to get the thickness you need. If you try laminating the foam, be sure you pull the protective plastic cover off first and use an adhesive that won't attack the foam.

Going with a plywood base with foam on top as Fred suggested will also work. In fact, that's what I did on my beach layout.

John

 

[SAL Comet]

Ha Fred,
I pretty much decided what you said, I have a friend at Lowe's that said he could get me some 2" foam. The problem there was it would be VERY expensive. So I'm thinking 1/2" plywood, with 1/2" homasote as the roadbed.
The reason foam sounded good is that I want to model the cut and fill that is the majority of my prototype line, and the foam would make it much easier to have elavations lower than track level. I'm guessing to do that with a plywood sub roadbed, the plywood would have to be removed? If so what would I do in such places? Screen wire and plaster? I can get 3/4" foam, is that to thin?
All advice welcome.

 

[SAL Comet]

Thank P.B., What kind of glue did you use to laminate the foam? I can get 3/4" foam to create the higher elivations, so I guess I could use it for the lower elivations also? After cuttting out the plywood?
Also, what did you use to attach the track to the foam? I have a lot of Atlas code 83 super flex track I had a friend give me, and it really likes to stay striaght.

 

[Fred_M]

Well Sal, that is the old cookie cutter method which is still hard to beat. You cut the roadbed out, elevate it, and use plaster and something for the ground. It's still a hard to beat method. Gluing up foam also works. Man, there a so many acceptable ways to do it that threads like this often become Ford v Chevy things. I agree that 2 and 3 inch foam is ouch,$$$, that's the biggest reason I haven't used it much myself. I like the cookie cutter and shell method too, because I'm cheap. LOL.. BTW, Shamus is redoing his fantastic On30 layout and he used... the cookie cutter method. He used 1/2 chip board with 1/2 sound board (simular to homasote) on it for road bed. He then used weaved carboard strips for the base for his plaster. I figure if it's good enough for him its good enough for me. But seriously, I use ceiling tile wire (bailing wire) and 3 inch masking tape with plaster soaked paper towels over it. The mistake some make on paper towels is they use the good expensive ones they steal from the kitchen. That's a horror story, use the cheap brown ones on the roll like you can liberate at the gas station, or if you can't find the chaep brown ones, the 3 rolls for a buck and a half wallmart ones are fair. But Bounty sticks in a gooey ball when soaked with plaster water. I love that broken arm cast material too, but it tends to get $. I think I would pass on laminating foam sheets together because I bet if you add the price of the sheets and glue it costs more than the 2" or 3" stuff net. The foanm I use I get at appliance places and construction sites and doing an little dumpster diving on ocassion. Besides, you can make better times in the alleys at rush hour anyway. The other day I found a old 30 inch solid oak door in the trash, perfect shape. I also have found load locks which I sold at the truck stop in 5 min. Boards, whole sheets of plywood. A back window for an S10 which the salvage yard gave me $50 for, the owner put in slider and threw the old one in the dumpster, a 2004 model? All on my way home from work driving the alleys. But that's prob more than you want to know. Have fun, Fred

 

[Bywaterrailroad]

I used the 1/2" pink stuff

Down south you just don't see the thick foam boad so I used the 1/2" pink board that you can find at the home DIY store, (Home Depot, Lowes). I built the table frame of 1x and used the cheep 1/2" "beaver-board" followed with a layer of the 1/2" pink stuff. I even attempted to use the pink stuff as a riser and grade change elevation system.....that was a mistake, not stiff enough. I had to rebuild with wood....a bit harder to cut out but worked lots better. I have some construction photos on my web page.

Nick Weber
New Orleans

 

[SAL Comet]

Ha Nick, Your layout room is similar to mine, except the knee walls in mine are only 2' high so the layout will be mounted to the slope of the ceiling. Which has made it really hard to work out the size, location, etc. Thanks for the info guys, it sounds like I should stick with the "cookie cutter" . I started putting some L girders together last night so I should have the first couple section ready to install soon.

 

[Matthyro]

I realize I am getting into this too late but want to show how I use 1/2" foam on my N gauge layout. Works fine for me. Not weak at all. Depth to back here is 16 inches.

 

[Matthyro]

This shows how it looks with a fascia board front. You don't even know that it is just 1/2" foam

 

[SAL Comet]

Ha Robin, How far apart are your supports? Also, what type roadbed are your tracks on? I can't really tell from the picture, thanks

 

[Glen Haasdyk]

I've just completed my benchwork. Its part cookie-cutter and part solid top. The frame is 3/4" ply cut into 3" strips and the sub-roadbed and table top is 5/8" ply. On the solid top I'll be useing 1/8" cork covering completly and the sub roadbed is the same cork cut into roadbed-width strips. Cork bought at the home improvement store is much cheaper that buying ready-made cork roadbed (about 1/5th here)

 

[farmer ron]

I have four of the modules that are going to make up part of the layout I have in the basement. I used 1/2 inch plywood then glued the 2 1/2 foam on top so I can cut out some land forms that go below the track level. On top of the foam I put a produce similar to homosote, called natrual dona cona board, this is what I glue my cork, the rolled sheet stuff that Glen mentions, then i glue my ties to this ( have a small logging theme layout and I hand lay my track). This way I can put screws in to hold the top fiber board on and the screws will go into the plywood. I like using this method as I can change the height of my foam if I want to by just just unscrewing it ranter than breaking it off and having to fight with the glued areas. Ron..

 

[Fred_M]

ops: LOL Robin. As big a clutz as I am I would stumble and put my arm clear through your layout. If I ever get up that way stand between me and your layout. Fred

 

[Russ Bellinis]

One guy in our ho modular club brought a nicely sceniced timesaver layout to a meeting one night for anybody to play with who wanted to. He used 1x4s for a perimeter frame, with 1x2 cross members every 12 inches. For the table top, he used a luan door skin with the track layed directly on the luan. The luan did not sag even a little bit. If I remember correctly the layout was 1' wide x 4' long (may have been 3"). It was very light and very sturdy.

 

[SAL Comet]

Ha Guys, That's for all the input. I agree with you Fred, I'd end up sticking my arm right thru Robin's layout (the Gerald Ford sindron). Sinse all my layout section are going to cantilever out from the slope ceiling, I decided to go with 1/2 plywood for structual rigidity it provides. I'm still undesided on the roadbed material. (homasote or foam) the faom is a lot cheaper,$7 a sheet vs. $25. Also still considering using layers of 3/4" foam for the above track grade areas. I'll figure that one out later, it's time to stop planning and start sawing. I have to get started before my girl backs out of the realestate deal I spent the last 3 mouths negotating!

 

[Matthyro]

Sal the spacers are 12inches apart. I use cork roadbed and glue it right to the foam with white glue.

 

[SAL Comet]

Ha Robin, Thanks for the info, I'm kinda suprised that white glue would stick to the slick surface of the foam. I'm thinking of using the foam on top of my plywood, mostly because of cost. It's good to know that white glue will stick to that stuff.

 

[Papa Bear]

Thank P.B., What kind of glue did you use to laminate the foam? I can get 3/4" foam to create the higher elivations, so I guess I could use it for the lower elivations also? After cuttting out the plywood?

I used Liquid Nails adhesive caulk between layers and to attach it to the wood frame. I started out at the bottom with a flat layer, then built up with contoured layers like a wedding cake. The track is 1 layer above the bottom to allow for scenery below the track.

Also, what did you use to attach the track to the foam? I have a lot of Atlas code 83 super flex track I had a friend give me, and it really likes to stay striaght.

My current layout uses Kato Unitrack, which I attached with double-stick tape. On a previous layout, I used flextrack on cork roadbed. I was able to keep the track positioned with track nails, but if that doesn't work for you, I would do like Matthyro suggested and use white glue.

I bet if you add the price of the sheets and glue it costs more than the 2" or 3" stuff net.

It does. I pay $7-8 a sheet for the 1/2" vs $26 a sheet for the 2". But, I'm building small layouts, so I would probably only use 1 or 2 sheets on a whole layout.

John

 

[60103]

On my previous layout, I used homasote for roadbed, about an inch wider than the track, and the glued foam under it in layers moving out. I also used various other bits including all the variations on sheets of X + plaster, plaster cloth, scenic pastes. It all works.
If you can't get economical foam sheets, use whatever's there.