3
3. Epoxy castings of a door and frame from an RTV
silicone mold produced from a 3D-printed mold box
are on the left. A freight door cast from an RTV silicone
mold made from a machined mold is on the right.
convention, one of the presentations was on making models
with this technology, and the resulting small structure models
looked very good. I decided to try it on a door with arched win-
dows in the transom that had been giving me trouble.
I made a 3D model of the door and frame and sent it to
Shapeways
to be produced in their
Frosted Ultra Detail (FUD) plastic. Although this process pro-
duces the finest detail available today, I soon got a reply that
they couldn’t produce the fine detail I was asking for. The
window mullions are 0.01” (0.25 mm) wide in HO, and the
material was too weak to support free-standing elements of
that size. I can easily cast details of this size, so I decided to
try something different.
