Brush-On Low-Expansion Polyurethane Foam?

[wazzou]

I just had a vision of you working in the train room wearing a clean suit. 

[C855B]

I do, however, try to wear a clean suit for concerts. Provided the dry cleaners is open that week.

[rodsup9000]

   Mike,
 If you go look for a "Joel Bragdon's geodesic scenery" DVD, it will show you how to get the land forms you want using foam. His foam is just about like the Smooth-On you tried, but doesn't have the expansion. For land forms, if I remember right, you place the mixed foam on a piece of plastic (saran wrap) and then add a second piece on top and roll it out to a thin layer. Then just before really kicks pull one side off and drape over your land forms.

 Maybe do a youtube search on it.

[nscalbitz]

I'm from the school of thought that irregular surfaces are both realistic and more easily obtained from raw model surfaces like foam.  Surfoam planing has few natural processes as an analog.  Heavy equipment produces these surfaces to some extent, but many modeled landscapes look more like parks than the typical natural or disused adjacent areas you often see near the tracks.

Some of the best surfaces I have produced have been paint over roughed foam (even beaded EPS) and covered with grout, a little foam and other texture finishes like static grass.

I've also used expanding foam to fill gaps and even did an entire mountain out of it on my current layout.  It has many advantages in the former application as @Sokramiketes illustrates, but I remain unconvinced that it is easier for surfaces because it is hard to dispense for that purpose.

Certainly agree with this; generally that adherence to some fallacy of 'correctness' is endemic in modelling and that frustrates the hell out of me who would rather see progress than procrastination. Anything can be recovered, re-covered and revised if it's that bad. Personally I've spent more time 'tarting up' others crass attempts at scenery than the reverse.

And while I'm no fan of latex paint (especially when they say... "well we wont see it"- but do!), unless there's valid need for some super-structured surface, just let it be... and move on. Experiemnt with parts and places. Again it won't matter...

[nscalbitz]

I must disagree with you, especially in N scale. If you don't start with a smooth base, you're going to have a moon crater scene. I'm not saying it needs a mirror finish...

And yet the Earth is crater like so many places.
The only smooth surface I need model for a Rio Grande branch would be a bowling/ golf green next to the tracks for a Denver suburb slot. The rest has to be random surfaces and textures with elevations and dips that could well hide  a man, beats or train.

That's part of the illusion our brains seek to identify the 'micro-scale' image of something we inherently know is vastly larger than we are- and could kill us in the stride of a T-Rex dinosaur (despite them now saying humans could out run them!).
Regds dave