paper towel + plaster - Model Railroader Magazine

It sounds like you've got it going pretty well.  The first time I built scenery, I was living in Coos Bay, Oregon.  Couldn't locate any Hydrocal nor the recommended industrial-strength paper towels.  So I substituted regular Plaster of Paris and regular kitchen paper towels with the fiber reinforcing (Terri brand, I think).  I didn't have much success with the masking tape and balled-up newspaper system for creating the "form" for the scenery.  And suspicious of how strong Plaster of Paris was compared to Hydrocal, I stapled some non-metallic window screen in place as my form.  Worked like a champ.  There is a group today that favors cardboard strips, hot glue and cheesecloth.  They just "paint" the plaster onto the cheesecloth - no paper towels.  I had already learned I could do the same with the window screen.

The advantages of plaster shell scenery (compared to foam) to me:

- the ease of visualizing and adjusting your land contours as you set up the forms (whether you use screen, cheesecloth, or cardboard strips).

- scenery is hollow underneath, leaving room for hidden track access, wiring, switch machines, and uncoupling ramps

- is naturally not flat.  You must carve nearly every square inch of foam to avoid flat spots.

- easily carved, detailed, and/or added on to.

- the shell can be colored a natural color by adding tint to the plaster mix.  Foam is inherently pink or blue.

- plaster shell is cheaper than foam

The advantages of foam (compared to plaster shell):

- lighter weight (although much of this is lost if you coat the foam with plaster)

- much easier to install trees (important if you are modeling a forested region)

- much easier to install buildings and structures "into" the ground

- some folks visualize the topography better by subtracting foam to arrive at desired result

- significant changes at a later date are much easier to make - just carve or glue on new foam

Both are very messy.  You must protect against plaster drips.  Mixing buckets and any application tools have to be cleaned.  Foam leaves dust and small pieces everywhere that must be vacuumed.

my thoughts, your choices

Fred W