# Styrofoam on Modular Layout Glue Question



## FishTruck (Feb 18, 2015)

Hi!

I am building a modular track which will live in my house during the winter season, and be stored in the garage for the rest of the year. I am planning to use Styrofoam with plaster cloth (woodland scenic style).

One of my modules is pretty big, and will have to be carried sideways. I am concerned that the Styrofoam and/or plaster cloth might be at risk to fall off the bench work. 

Here is my question. 

Can I follow the woodland scenic instructions and glue the layers of Styrofoam, risers, plaster cloth, ballast and track... or, do I need to do something special to make sure it can withstand tilting to 90 degrees?

I have read that "clear caulk" is the best adhesive. Thanks for any advice!


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## cole226 (Feb 8, 2013)

i've always used liquid nails adhesive. and they do make one that says its for foamboard.
you can still put a few screws in it.


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## flyboy2610 (Jan 20, 2010)

I would go with a foam safe construction adhesive, such as Liquid Nails. Loc-Tite makes one as well. They would be much stronger than caulk for your application. Caulk is excellent for gluing down roadbed and track, however.


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## CTValleyRR (Jul 26, 2014)

When I was ripping apart my last layout, foam that had been glued together with hot glue and covered with plaster cloth needed a two-handed tug at full strength to pull it out. I think it would be strong enough to support its own weight when carried sideways.


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## FishTruck (Feb 18, 2015)

Thanks Guys!!


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## flyboy2610 (Jan 20, 2010)

CTValleyRR said:


> When I was ripping apart my last layout, foam that had been glued together with hot glue and covered with plaster cloth needed a two-handed tug at full strength to pull it out. I think it would be strong enough to support its own weight when carried sideways.


I was just responding to the "clear caulk is the best adhesive" statement. I'm sure that hot glue is stronger than clear caulk.


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## grashley (Aug 27, 2015)

Good advice. 

One issue I have run into: If you use Woodland Scenic BRAND styrofoam, glue, etc, you should be okay with your plaster, etc. I tried to use their plaster product on construction grade styrofoam and on wood to make terrain. IT WOULD NOT STICK AT ALL. When I contacted the company, they told me it was designed to stick to THEIR foam, and not designed to stick to wood or construction foam.


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## johnfl68 (Feb 1, 2015)

You could always add a couple long drywall screws (3-5 inch long) through the styrofoam along the middle with about a 1" x 1" piece of scrap styrene as a washer on top, just screwing about 1/4" - to 1/2" or so into the benchwork. This could be done while you build and be covered over.

This would help support the styrofoam when carried sideways.

Put some notes on the bottom of the benchwork with a sharpie as to where they are located, as a reminder if you ever tear it apart years from now.

John


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## CTValleyRR (Jul 26, 2014)

grashley said:


> Good advice.
> 
> One issue I have run into: If you use Woodland Scenic BRAND styrofoam, glue, etc, you should be okay with your plaster, etc. I tried to use their plaster product on construction grade styrofoam and on wood to make terrain. IT WOULD NOT STICK AT ALL. When I contacted the company, they told me it was designed to stick to THEIR foam, and not designed to stick to wood or construction foam.


Interesting. I had WS foam, packing crate foam, newspaper, plywood, and extruded foam panel. Their plaster cloth stuck to all of it (I had to use a putty knife to scrape it off some of the wood that I was reusing). I wonder if they've changed their formulation.... or if it's a marketing gimmick to get you to buy their stuff.


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## grashley (Aug 27, 2015)

The specific WS product was Lightweight Hydrocal. I tried to use it to raise ground level on a 1x6 side board and sculpt a mountain on structural foam. It absolutely refised to bond to either.


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## CTValleyRR (Jul 26, 2014)

grashley said:


> The specific WS product was Lightweight Hydrocal. I tried to use it to raise ground level on a 1x6 side board and sculpt a mountain on structural foam. It absolutely refised to bond to either.


Ah. I use Sculptamold for that purpose. I find Sculptmold to be a much more versatile product than hydrocal (except for casting). It will stick to darned near anything. It 's a little heavier than plaster, but it's cheaper.


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## grashley (Aug 27, 2015)

CTValleyRR said:


> Ah. I use Sculptamold for that purpose. I find Sculptmold to be a much more versatile product than hydrocal (except for casting). It will stick to darned near anything. It 's a little heavier than plaster, but it's cheaper.


I agree. That is what I used when the other failed. The WS was available locally. I had to order Sculptamold on line. Sculptamold is GREAT stuff. The water / product ratio is very forgiving. You have 20 minutes + to use the mix, but it firms up very quickly, less than an hour. When dry, it can be cut with a knife, sanded, filed, chiseled (with care) or covered with spackling. I love it!!!


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## gunrunnerjohn (Nov 10, 2010)

For most of the scenery like bridges, mountains, etc. we start with 2" foam and then use wallboard compound to finish the structure. It's dirt cheap and very easy to work. The bridge and stone wall both were all done with wallboard compound. Harry Henning carved the individual bricks on that bridge, definitely a labor of love!


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## CTValleyRR (Jul 26, 2014)

You don't have trouble with the wallboard compound cracking as it dries? I tried it once and had no end of troubles.


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## gunrunnerjohn (Nov 10, 2010)

You must be using the wrong compound, we use the powder and mix it. I've never seen any cracking issues. If it cracked, it would be pretty worthless for wallboard use as well.


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## CTValleyRR (Jul 26, 2014)

Maybe I just had a bad batch.


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## gunrunnerjohn (Nov 10, 2010)

If you mix it wrong, I've been told it could crack. Also, you can't put it on too thick, about 1/8" or so is all you can do in one coat. I believe there are also multiple types of joint compound, perhaps we're lucky in our selection.


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## DonR (Oct 18, 2012)

CTValleyRR said:


> You don't have trouble with the wallboard compound cracking as it dries? I tried it once and had no end of troubles.


If you put it on too thick it will crack as it dries. Use it as a thin
top coat of 1/4 to 1/2 inch thickness and it will do OK. 
I tried the powder mix. Easier to
use only what you need from the compound container, cap it and save the
rest for next project. It's also less messy.

It does seem to mold in the container. You might
have to scrape that off.

Don


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## CTValleyRR (Jul 26, 2014)

Well, clearly I could have experimented with it a little more, but I'll stick with Sculptamold. Much more forgiving, it seems.


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