# Weatherproof foam core board



## marioporto (Jul 22, 2020)

Hello everyone. I'm looking to source some foam core board that I can use to scratch build structures. I have used some before but can't recall who I bought it from and i do recall that it was quite expensive. Have any of you ever used the material that is used for outdoor signs? It seems like it should work. Looking forward to some feedback and it's nice to be a member of this group!

Mario Porto
Bergen County. NJ


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## placitassteam (Jan 2, 2008)

I am not sure exactly what you are referring to. the stuff I am familiar with is foam with paper on the outside, not good for outdoors. One of the guys on this has done some beautiful buildings using a solid foam which was quite expensive. I wrote an article for the Garden Railways Oct. 2018 magazine detailing building structures using 1/2 inch foam insulation board which is about $10 for a 4 X 8 foot sheet. There are a number of projects on this forum I have posted under the handle placitassteam.


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## Naptowneng (Jun 14, 2010)

Sign building material is called Coroplast, very common and easily obtained from sign shops

eg.: https://www.homedepot.com/p/Coropla...te-Corrugated-Plastic-Sheet-CP4896S/205351385

Jerry


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## placitassteam (Jan 2, 2008)

I have used the material that Jerry mentions especially for sub roofs. It is very stable and can be obtained for free after elections as a lot of political signs are made from it.


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## Ironton (Jan 2, 2008)

What you might be interested in the foam core board sold in Dollar General or other dollar stores. This is designed to be used by crafters and the paper peels off easily. Then you have a thin polystyrene board to build with.


Hope it helps.


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## James Kuhns (Jan 12, 2008)

The stuff you are probably looking for is a PVC foam board, very stiff and comes in colors and varying thickness. One on the brand names is Sintra. It is supplied by any of several company's that supply plastics. One of the supplier in San Diego is Ridout. There are others that maybe a little cheaper. This material is used in outdoor signs. I have used it on my railroad for years and it stands up to UV quit well.


James


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## marioporto (Jul 22, 2020)

Thanks everyone, great suggestions.


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## toddalin (Jan 4, 2008)

...Or you could make your structures out of styrofoam and add a layer of hydraulic cement.

Simply sift it over the foam with a strainer and alternately use a spray bottle with water to wet it. You can even alter the final layer between "stucco" and "concrete" by how much water you spray during the final coat.

Sift then spray generously for a smooth cement finish or spray then sift for a textured finish. I have lots of structures (e.g., bridges, ramps) and buildings built this way and they last a very long time outdoors in the elements.

Here's what to use.


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## denray (Jan 5, 2008)

Mario
The only thing that makes me think that you mite be refering to Presision Board is you stated it is quite expensive. 
It is used for outdoor signage, and with stands all the different weathers VERY WELL. 
https://precisionboard.com/, It is easy to machine with any woodworking tools and weathers great.







[/url]IMG_4951 by Dennis Rayon, on Flickr[/IMG]
This is a structure I built out of precision board
Dennis


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