# Plaster of Paris vs Drywall compound



## piperman (Jan 17, 2015)

On my last layout I used Plaster of Paris for mountain building. I'm wondering if I can use Drywall Compound instead. I'm thinking that Drywall Compound won't set up so fast. Problem I found last time with Plaster of Paris is it dry's so fast in the mixing bucket I end up chucking out a fair bit.
What is your experience?
Regards
Piperman


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## mikek (Dec 29, 2013)

Thick drywall takes long to cure, and may crack as it dries. Look into liquids or additives that will slow down plaster drying time, I bet they are out there.
I checked Google, vinegar, citric acid (lemon juice). These are mild acids. Experiment with small batches.


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## wvgca (Jan 21, 2013)

plaster of paris, once set or cured, is not water soluble, regular drywall compound is ... some drywall [dry powder- not premixed] does cure and is not water soluble later on, these are usually marked ith 'cure times' 45, 60, 90 minute ...and are normally used for drywall in wet areas or bathrooms, etc ... any premixed tubs of compound can be softened later on by water spray, comes in handy sometimes for changes ...


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## CTValleyRR (Jul 26, 2014)

I use a product called Sculptamold. It is basically a mixture of plaster, powdered white glue, and shredded newsprint. I spread it over rough landforms made of carved foam insulating boards, but it can be used over screen / wire mesh, newspaper, cardboard lattice or any other foundation. 

It has a much longer working time than plaster does, about 30 minutes, but it isn't as sensitive to moisture content as plaster, so that if it starts to harden on you, just add a little more water. I have a 2 cup mixing bowl and a 2 qt one. I use the small one for small areas and careful application, and the large one to cover larger areas, where I'm just slopping it on and spreading it.

It can be bought in 3, 10, 25, or 50 pound bags. I can usually find good deals at local art supply or craft stores, but it's available on Amazon.com too (just watch the prices, because some private sellers way overcharge for the stuff).


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## DonR (Oct 18, 2012)

You might try making your own plaster cloth by soaking
gauze or veil type material in a somewhat diluted dry wall paste
then applying that over the wadded newspapers or whatever
you use for a base. 

Dry wall paste is designed to be applies thinly, thus, if you try
to put it on too thick it will crack. Yes, it did for me.

Don


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## SBRacing (Mar 11, 2015)

My greandpa used drywall putty all the time when i was little. And later in life when I became better at scenery I tore down some of his stuff and that drywall putty was to hard to rip up. Never used plaster of paris, I have alwayes used foam sheets, Stuff (foam in a can), and foam putty by WS.


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## Cycleops (Dec 6, 2014)

Yes, POP just dries too fast if you mix it and use it 'neat'. Dons idea of finding some sort of scrim, or maybe medical gauze is good. There used to be a product in the UK which I've used called 'Modroc' which came as a a gauze with POP impregnated into it and it worked very well over crunched up paper.


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## Water Stop (Apr 18, 2015)

Why mess with all that?

Buy ready-made mountains from Home Depot! 

Just plop 'em down on your layout, spread a few rocks, gravel, and sand round the base, and you've got *THIS!*

(O-scale shown...your mountains will appear to be almost _twice _as tall in HO scale!)

Water Stop


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## CTValleyRR (Jul 26, 2014)

If you're satisfied with that, great. Many of us aren't, however.

Gauze impregnated with plaster is available in from many sources, including our very own Woodland Scenics. Many craft stores, most medical supply places, and most educational supply places carry it more cheaply.


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