Diorama Tip: DIY Sculptamold

[PHPaul]

Sculptamold is a common material for building larger terrain features.  It's basically paper fiber mixed with plaster powder and works much like plaster but is lighter and goes further than plain plaster.

However, it is - at least on my budget - expensive with a 3 pound bag running around $20US.  For larger dioramas and model train layouts, 3 pounds doesn't go very far.

There are a number of Youtube videos on how to make your own.  The consensus seems to be that the best source of paper fiber is the gray paper egg cartons.  The cartons are torn up into small pieces and then chopped into fine fibers with a blender.  The video I watched chopped them dry, but that didn't work worth a hoot in my old cast-off single knife blender.

After some experimentation, I found the following "recipe" works best for me:

1 egg carton

20oz of water

2 cups of plaster of paris.

Put about half the water in the blender.  Add torn up bits of carton slowly, adding more bits as they are reduced to a slurry.  Add more water as needed to keep the mixture about the consistency of sloppy oatmeal.

When the entire carton has been reduced to slurry, pour it into a bowl and add the plaster of paris in roughly 1/2 cup portions, mixing thoroughly as you go.

Obviously, this mixture is for immediate use but one batch will cover quite a bit of area.  Working time is dependent on how wet the mix is.  The proportions I listed worked well for me, the mixture held it's shape and working time was more than adequate.

Edited March 25, 2024 by PHPaul

[Rick L]

I helped a friend with his train layout years ago collecting homasote fibers through a jointer. As I recall, he added his plaster material in the same manner.

[dave branson]

In your picture what is the blue material called and were can I get some of it.

[BDSchindler]

When I did our Racetrack in the basement, I used scrunched up newspaper and covered it with cheesecloth (about $6 for 45 yards) impregnated with Plaster of paris ($11 for 4 pounds dry).  I just cut strips of the cheesecloth and once it dried painted it green or tan depending on what the surface of the landscape was to be (grass vs. dirt) then sprinkled Woodland Scenics grass or real dirt saturating it with thinned down Elmer's white glue.

For chunks of rock, Woodland Scenics train track balast and in some cases. real pebbles

The result...

Edited March 27, 2024 by BDSchindler

[NOBLNG]

9 hours ago, dave branson said:

In your picture what is the blue material called and were can I get some of it.

I think that is just styrofoam sm. Any building supply store would have 2’x8’ sheets in different thicknesses.

Edited March 27, 2024 by NOBLNG

[dave branson]

thank you

 

[PHPaul]

18 hours ago, dave branson said:

In your picture what is the blue material called and were can I get some of it.

NOBLING is correct, styrofoam insulation board.  Great for building up thickness, light and easy to carve with a hot knife.

Edited March 27, 2024 by PHPaul

[PHPaul]

After further testing, a couple of notes:

1.  Blending the fiber goes MUCH faster and more thoroughly if you pre-soak the torn up carton in water with a drop of dish soap.  I put it in to soak and went off to do other things so I don't know exactly how long but it was thoroughly soaked and I actually wrung it lightly before popping it in the blender.

2.  This should have been obvious, but the more plaster you add the quicker and stronger it sets up.  Of course working time is reduced but not inconveniently so.

 

Edited March 28, 2024 by PHPaul