# New to foam



## B.M. Sturgis (4 mo ago)

Hello all. I'm new to using pink extruded foam and would like to know the best way to cover flat areas which will be modeled as lots near cities and the like. Do I cover with plaster or some similar product, paint or what? Thanks for any advice.


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## OilValleyRy (Oct 3, 2021)

IMO it depends on the lot.

For grassy city lots: green or brown paint covered in ground foam etc. Don’t spend full price. Check the “oops paint” which is mis-matched batches on clearance. Every big box has a rack, which changes weekly.

For a parking lot etc: I’d use a thin layer of dyed plaster. Dye can be acrylic paint. This means if it chips etc, the area won’t be white. By using plaster you can add pot holes, cracks, broken surfaces, man hole covers, etc.

Just my opinion.


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## JeffHurl (Apr 22, 2021)

I used plaster cloth on my entire layout, and I am very happy with the results. But it does leave seams unless you smooth everything out with a then coating of more plaster. Some people also use drywall mud instead of the additional plaster. I used both, and just "painted" it on with a cheap paint brush after the plaster cloth had dried. 

Then, I pained the whole thing a light tannish brown... used gaffer's tape for streets, and sprinkled on some grass "turf," some trees, structures, etc.

Beginning the plaster cloth:
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One of teh benefits of using plaster cloth, is that you can mold rocks using plaster molds. You just "glue them in place with more plaster, lol!









Some paint and grass





























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## B.M. Sturgis (4 mo ago)

Thank you both for giving me some direction. This is my first layout with a foam base. In the past, it was plywood with plaster, but that tended to crack with changes in humidity. I chose foam for this layout to avoid some of that. I'll try to post pictures.


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## JeffHurl (Apr 22, 2021)

Hopefully the foam is less prone to swell and shrink with changes in humidity.


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## Mixed Freight (Aug 31, 2019)

B.M. Sturgis said:


> Hello all. I'm new to using pink extruded foam and would like to know the best way to cover flat areas which will be modeled as lots near cities and the like. Do I cover with plaster or some similar product, paint or what? Thanks for any advice.


In my experience, you can use whatever the heck you want (or not). Sheets of styrene plastic, cork, cardboard, card stock, paper, plaster cloth, drywall plaster, spackling compound, latex paint, sanded grout (makes excellent gravel, IMHO), or anything else that you might deem suitable. If it ain't the right color, then paint it as required.

After laying down sheets of pink or blue foam, a quick coat of flat latex house paint will toughen up the surface. Use a good ground-type color (light tan or light gray or similar), and it will also make the foam a lot more palatable until you can come in later with some serious scenery work.

Incidentally, pink and blue foam are impervious to moisture. You can use all the water-based scenery techniques you want with no fear of swelling or shrinking.


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## Millstonemike (Aug 9, 2018)

OilValleyRy said:


> ... For grassy city lots: green or brown paint covered in ground foam etc. Don’t spend full price. Check the “oops paint” which is mis-matched batches on clearance. Every big box has a rack, which changes weekly. ...
> 
> Just my opinion.


What he said ^ ... especially for large areas (like 8'+ x 4'+). And ask the Big-Box paint guy to change the color. They'll do that for their paint, even after you've returned and used some.

You don't need a $50 gallon for small areas. You can buy an 8 oz sample expertly mixed to your color of choice using the in-store paper swatches. $6+. I'll be buying a colored sample at HD tomorrow ... Christmas layout building


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## CTValleyRR (Jul 26, 2014)

JeffHurl said:


> Hopefully the foam is less prone to swell and shrink with changes in humidity.


Hopefully? Foam is dimensionally stable with respect to changes in temp, and is impermeable to water. That's why it's used as home insulation. No hoping necessary.


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## JeffHurl (Apr 22, 2021)

It was a courtesy using "hopefully" but thanks for picking that nit for me.


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## wvgca (Jan 21, 2013)

water doesn't bother high density foam .... that's why it's used a basement / foundation insulation ...
and the only difference between pink, blue and green foam is the manufacturer , white bead board foam board is whole different animal ..


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## B.M. Sturgis (4 mo ago)

Thanks all. I didn't mean to stir up a hornet's nest. I'll be carving out some ditches and river beds soon plus building some small elevations - hills not mountains - then painting a base with foliage over it. It's a 3x6 n scale, so plenty of room. I've been happy with some practice pieces where I carved rock walls into stacked foam and then painted, but I wanted to know if it is more traditional to apply a coat of plaster first. All of my previous layouts have been plaster over wire mesh. Old school.


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## CTValleyRR (Jul 26, 2014)

People do it both ways. I personally use a thin (~1/8") layer of Sculptamold over my foam. It helps to break up the dead flat look of the foam, and hides some minor imperfections (sometimes, the lettering on the foam is slightly indented, and still shows up through a coat of paint). Both ways work, though.


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