Model Railroading > Using extruded foam board for bench work

Our club is getting ready to start building our new HO layout. We are a few weeks away from starting bench work. Our old layout was built using plywood with a layer of homasote up top of it. We haven't really decided how to do the current layout but extruded foam sheets are an option. For those that use it, have you had any problems associated with the foam? If you're layout uses another technique, what do you use? I'm hoping to gather information to share with other members to help determine which way to go. Thanks for any help you guys can offer.

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I have built my N scale around the wall/island layout using 1x4 framing with the blue dow board glued to the 1x4's without a problem. Unless you really hit the foam board from below, I don't think it would pop off the wood. I used a foam compatible liquid nail adhesive.

Framing areas range from 2'x2' to 2'x3' grid depending on wall length, etc.

I have also used adhesive to glue down the cork with great results.

Mike

I have a 30"x8' module I made with extrude foam, It transfers noise readily and not really the best option.

Ted Curphey
Ontario, OR

Is there a trick to reducing the sound on the foam?

Ryan Wilkerson
Fair Oaks, CA

I found that using Woodland Scenics soft foam roadbed dulled the sound.

A fellow I know used that AMI sticky type roadbed and it worked even better.

Mike Bannon
St Catharines, ON

I second the soft foam roadbed glued down with liquid caulk . I hear nothing but the motors on the locomotives .

I'm curious as to the comments that keep being made on this and other forums about foam being noisy.

My current layout is double deck with 2" foam glued and screwed to 1x2 and 1x3 supports on roughly 16" centers. The track is laid on thin luan plywood (used to hold the spikes - I hand laid the track) which was glued to the top of the foam. It is also fully ballasted and sceniced. It is DEAD quiet. My staging yard, however, is thinner foam (used for lower cost and some needed additional clearance) with flex track glued directly to the foam and fewer cross supports. It does drum somewhat.

Additionally, I recently had the chance to visit an HOn3 layout that was built ENTIRELY of foam (benchwork, roadbed... even the support legs!) and it was silent as well.

Based on these experiences I suggest that the thickness of the foam and what method you use to mount the track may make a significant difference in the end result.

Having said that, I love the ease of construction and the ease of doing scenery with the foam (easy to shape/carev away and "plant" trees, etc. into). I would certainly suggest at least experimenting with it.

Bill Schneider
http://home.comcast.net/~oandw/

Based on other discussion threads (here and in several YahoGroups) regarding foam board noise the key to reducing the "drumming" and resonance is to have at least one layer of a dissimilar material between the track and the foam.

Have been to and operated on at least three shelf-type walkaround layouts than do not have ANY plywood support under the foam, just small pieces of dimensional lumber (1x2, 1x3) either made into L-girders to support the foam or glued to the foam as cleats to screw shelf brackets into. The quiestest of the three used VinylBed glued to the foam (anybody know if this product is still available?), the other two used cork. All exhibited at least a little resonating wheel noise, none of which seemed objectionable to me.

BTW, here's the big eye-opener for me: Even without any plywood underlayment or box-grid support, all three were plenty study to hold the trains and scenery up with no problems. Sure, you can't jump and and down on it, but why in God's name should you have to??

My take-away from all this was you can save a LOT of $$ and construction time by not over-engineering your benchwork, which seems to be an affliction many of us have.

NZ

I used HomaBed roadbed glued with foam friendly Liquid Nails onto 3" thick slabs of Dow Styrofoam©. I never experienced any appreciable noise level versus cork over plywood or Homasote over plywood. Benchwork framing was a combination of conventional L-Girder and open grid.

Some images below of the old layout. The first one shows the yard which was nice and flat and foam board. The last two show before after shots of the mill area with a road dropping down to the middle right of the two pics. The roadway was carved out of several layers of foam and made for a nice 'cut' as well as providing a place for the double track trestle to cross the roadway. Sadly this layout is no more having been dismantled in June 2003. (Still bummed!!)

As others have said..."Your mileage may vary"...

SV



Edited 1 time(s). Last edit at 08/19/13 17:50 by SandingValve.

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Thanks for all of the input. There are a few areas I believe would be good to try the foam method as long as everyone at the club agrees to it.

I have never been big fan of gluing track down right off the bat because glue tends to be a little too permanent as a first measure. I like the option of adjusting or revising track geometry during the early phases. Thus I prefer track nails or spikes, which can be easily removed.

The homabed on foam does allow track nails or spikes which seems appealing. Otherwise I expect I will only use foam for area's not requiring track subroadbed. I have never compared cost of foam vs plywood, but in area's not needing a yard, thin sections are all I ever use, just enough to hold the track.

If you feel comfortable that you can glue track down and get the geometry dead-on first time, then maybe foam is a good option for you.

I've always put down a 1/2" of plywood then the foam on top of it. Maybe this time around I'll just use the foam.

At any hardware store, foam board seems to be higher priced than plywood. However, i look on craigslist to see if I can save some money. I hardly ever find plywood but there always seems to be contractors selling extruded foam board. Some of it didn't pass the requirements for a building project or is just left over. I have seen 4x8 sheets that are 2 inches thick on there for $3-5 per sheet.

On my dad and I's last HO layout we used shelving board. It was less expensive than plywood and looked better, had a flatter surface and held nails and anything else. We could also jump up and down on it.

I have several N scale friends (well they are real sized but they do N scale) who use foam instead of wood. With N I do not notice that much noise after things are scenicked. I too plan on using foam instead of wood for a shelf layout that will probably not happen until next year at best, if anything just for less weight. I have two rolls of the Woodland Scenic foam stuff so I might use it under KATO track just to deaden the sound after what has been mentioned here. My mom threw away the boxes and that was as far as she got on building her own N scale layout several years ago so I may as well use it for something.

Jim

harrier09 Wrote:
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> At any hardware store, foam board seems to be
> higher priced than plywood. However, i look on
> craigslist to see if I can save some money. I
> hardly ever find plywood but there always seems to
> be contractors selling extruded foam board. Some
> of it didn't pass the requirements for a building
> project or is just left over. I have seen 4x8
> sheets that are 2 inches thick on there for $3-5
> per sheet.

Cool! That is one heck a useful modeling tip!

Jim

I didn't get that good a deal but I did find some on craigslist. Too much for my use and I WISH it was that cheap!

tq-07fan Wrote:
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> harrier09 Wrote:
> --------------------------------------------------
> -----
> > At any hardware store, foam board seems to be
> > higher priced than plywood. However, i look on
> > craigslist to see if I can save some money. I
> > hardly ever find plywood but there always seems
> to
> > be contractors selling extruded foam board.
> Some
> > of it didn't pass the requirements for a
> building
> > project or is just left over. I have seen 4x8
> > sheets that are 2 inches thick on there for
> $3-5
> > per sheet.
>
> Cool! That is one heck a useful modeling tip!
>
> Jim

Ryan Wilkerson
Fair Oaks, CA