Is foam board really required

Model Railroader Layouts and layout building
1

I’m wondering if I could scrap the idea of using foam board on top of my layout. I’ve got this stuff 2" thick on top of 3/4" plywood, and I’m wondering if maybe I should just attach the track and roadbed directly to the plywood. I figure that would be enough that I could use Atlas under-table switch machines or a Tortoise since the combined thickness I’m guessing (plywood + roadbed) would be right at 1".

Might be better in the long run, I’m thinking, because I could wire under the layout and not have to have really long lengths of wire. Since the water feature I’m planning would not be very deep, I’m not sure it’s worth making a 14’ deep (approximately 2" in HO scale) water feature, instead making a bridge over the creek.

2

You don’t have to use foam board at all if you don’t want to use it. There are other methods for scenery that work just as well.

I attach my roadbed directly to strips of plywood that are mounted on risers. I do use foam board stacked and carved for landforms. And then I paint on plaster and attach rock molds to the foam board.

If you have you plywood base attached to risers, you can stack foam board below track grade and carve away at for your creek.

Craig

3

You see, that’s kind of what I thought. I’m having a heck of a time getting the foam board back together and I could always use pieces of it for mountains and the like. And, yes, I do know not to cut it with a hot wire cutter.

So I get like maybe a 1" riser set and put the water under that, forming it directly on the table, right?

I got some really good plywood, so I think I’ll do that. I got to thinking of a layout a friend of my father’s showed me one time, and I didn’t see any foam board. Plus, with the table one of my coworkers built for me, it looks pretty level as it is.

I assume I need to paint the plywood top first, or at least paint it when I get the roadbed laid down (which won’t be for a while as I was recommended to get the layout working the way I wanted it first). Any suggestions?

4

The risers I am talking about are part of the bench work. They hold up the plywood that is usually cut out cookie cutter style.

But yes, you can buy the foam riser set to change track grades if you are building on a flat surface such as a hollow core door or sheet of plywood.

Craig

5

That’s exactly what I’m doing. Not against cutting out plywood, but I’m going to mangle the board enough as it is.

Okay, I’ll try it without the foam board. Seemed to work before, and I can mount the switch machines under the layout.

At this point, I can always go back to foam board, but this will give me greater flexibility.

6

Nothing is really required. There are many combinations that work well. But the idea that switch motors won’t work with foam - I actually have 4" total of foam on top of 1/4" plywood and there are no issues with mounting my turnout motors. I happen to be using servos, with the Motrak mounting brackets, but that makes them end up being pretty much exactly like a Tortoise. Nothing special needs to be done, I just use longer pieces of piano wire than come with the Motrak mounts.

With just plywood you can glue a servo directly to the plywood. which is how my friend has been doing his. That might not work with layers of foam on top.

----Randy

7

I’ve been using 2 inch foam over plywood for the last couple of layouts and have no problems with tortoise machines. Just use thicker music wire. Foam is never required but it does lower the noise level and give you more options with scenery.

8

I found that the plywood isn’t necessary. I have lightweight benchwork and just 2-inch foam - no plywood at all.

9

To answer your basic question, NO foam is nto needed.

Some build their layout with a plywood only base.

SOme build with a luan plywood and cover it with foam.

Some build with rigid foam on an open grid framework of 1 by’s.

Some build a layouout table tehn build up the scenery with wads of paper covered with plaster of paris.

Some build the table then use the foam to create changes in terrain.

Some build a layout base that is all different heights to get terrain effects they want.

YOu can build you layout however you want. There is NO “carved in stone” or “hard fast rules”.

One of the ideas behind using the foam is that it creats a lighter weight layout should you have to move it.

10

I would disagree. It seems to me you are letting your choice of switch machines drive your scenery. There are many alternatives to Atlas under-the-table switch machines that don’t have the 1" limitation; some of these were discussed in your other thread. To me, switch machines don’t do much to help me create the desired final effect of my layout - the depth of a water feature definitely does. So I would give the water feature priority. That doesn’t mean you have to use foam to get where you want to go; there are many alternatives there as well.

I think that often on early layouts in one’s model railroading “career”, one tends to forget that a flat table top is not a necessary element for building a layout. You can have places where foam and/or plywood don’t exist - places where you can see the floor until the scenery is put in. The only parts of the layout that have to have something like foam and/or plywood is under the track - the rest is optional.

I personally don’t think laying the track straight on the plywood is a great idea. I would use some kind of roadbed, with cork being my least favorite personall

11

My layout is built on a 2" x 4" frame with 1/2" plywood as the surface.

I drill 5/8" diameter holes in the plywood to mount my Tortoises.

The roadbed is 5mm Woodland Scenics Foam Track Bed.

I see no use for foam board on my layout. Where bridges need to span water, I just remove an area of the plywood and built auxiliary supports out of plywood to support the bridge and trains running over the water.

Rich

12

One of the nice things about foam over plywood is that if you decide to do any major changes, the foam will pull right up with the scenery on it. Underneath you’ll have bare plywood to start over with another layer of foam…

13

One word, Sir, Homasote.

Jimmy

14

One word, just foam, easy to cut and fix if you want to change something (and you will). Also you said something about not using a hot wire, as long as you use a hot wire less than 450 degrees, like WS’s, no problem, you go (if I remember right) over 467 degrees and you can emit toxins!!!

15

When I make my benchwork, instead of using a sheet of plywood under the foam, I nail 2" wide strips around the top edge of the frame of the benchwork. This gives me more surface to glue the foam to. When I used a full sheet of plywood, I found it a PITA to wire the track. I have areas of my layout, where the track is on top of foam up to 12" thick. I made a tool out of a wire hanger that works pretty much like a sewing needle to pull the wire through.

I sanded a point onto one end of a straightened wire hanger with a bench sander.

I flattened the other end of the hanger with a hammer and bench vise. Then, I drilled a hole in the end. Thread the wire through the "eye’, and twist it around the end. Push the pointed end through the foam, then pull the wire through.

16

If foamboard disappeared from the planet, I wouldn’t miss it.

17

Homasote is awfully heavy. Is it really worth using?

18

When you say “just foam” what kind are you talking about?

19

Homasote works just fine for roadbed, provided you support it with something solid. I’d think the weight wouldn’t be a concern except for large portable sections that were intended to be moved frequently.

20

Two inch blue, pink, whatever, personally I use the white beaded as the other stuff is usually not available to me on the west coast