I have discovered on the internet a new technique for cutting stonework that is so much easier than carving plaster with an X-acto knife. Some of you might be able to use it.

Start with a sheet of Elmer's Foam Board. I believe it comes in different thicknesses and colors. I used 3/16" thick that was green on one side. Available at Michael's in their picture matting department.

Always use a NEW single edge razor blade to cut the foam. Any nicks in the blade will give you a ragged edge. After cutting the pieces to size the paper on one side must be removed to expose the foam. On the arch to the left I removed the white side, and it wasn't easy, requiring repeated steps of wetting the paper and peeling it off one thin layer at a time. On the arch to the right I removed the green side and discovered that it can be peeled off in one piece without wetting.

You can see how the green side peels off in one piece.

Side of viaduct has been glued on and is now ready for the stone cutting.

No X-acto knife is needed. All you need is a straightedge and a sharp pencil.

All the stone cutting is finished. Really a fast job compared to using plaster.

Finished viaduct, stained with a mixture of india ink and alcohol. The foam takes the stain very well. Just experiment on the ratio of ink to alcohol on scrap pieces until you get the shade you want. I start with a peanut butter jar half filled with alcohol and add a little ink at a time until I get it right.
Copyright(c) 2012 Bill Defoe, Division Two, NMRA-MCR . All Rights Reserved.
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