Foam....an expanding question

n-scaler-dude

New Member
I was just at my parents house tonight where my dad had a can of expanding foam insulating material laying around.

Is this something that has been tried by anyone for scenery? Maybe just for filling in small holes or anything??

It seems like it could have some use. When it dries it's pretty stout and can be cut easily with a blade, and it sticks to almost anything it touches.

Excuse my beginner question, but inquiring minds want to know.
 

Lighthorseman

Active Member
Expanding Foam...

The first I ever heard of this was reading articles about Mal Furlow's "San Juan Central", a smallish HOn3 layout made for Model Railroader magazine. I have not tried it myself, but will be following this thread with interest. I am hoping for POSTED PICTURES!!! :)
 

n-scaler-dude

New Member
Just found a thread on the n/z board (Copper Ridge Railway), where expanding foam was used to create scenery. Lot's of pic's and posts, and a very interesting thread.

The foam looks like a wonder product for fast scenery.
 

jon-monon

Active Member
A recent MR article used the stuff. They made a big viaduct out of plastic sheet, filled her with foam, and covered it with brick paper. Looked good. They said they did it to save on weight.
 

spitfire

Active Member
Hi n-scaler dude!

I seem to remember reading recently on either this forum or another one about using expanding foam. The key word is e-x-p-a-n-d-i-n-g..

In other words, it keeps expanding even after you stop spraying so it's best to apply less than you think you need. The guy who tried it said this caused a problem on his layout as the expansion caused some existing scenery and track to be forced out of position and he had to do a fair bit of repairing afterwards.

I guess the thing to do would be to try it on a scrap piece of ply or cardboard first, til you get a good feel for how much it continues to expand.

Hope this helps.

Cheers
:p Val
 

n-scaler-dude

New Member
I can attest that he is right, it keeps on expanding. I've used it for sealing drafty windows and door frames, so I guess that makes me an experienced user of GS?

Maybe the trick is to NOT apply it under roadways and allow it to push it up. Maybe use the crumpled newspaper trick under any roadbed, and apply the GS on top of it. Don't worry, I'm sure it'll stick. It sticks to almost anything, I can also attest to that?:)
 

pcentral

Member
I have read threads about this somewhere also. Some people have said it is hard to carve for rock castings, etc. I have also heard the problems of E X P A N S I O N. I use a specially designed for railroading foam. I know I have mentioned this before but I can't say enough about how great this stuff is. I shudder every time I hear of someone using plaster or Hydrocal for scenery and taking forever to finish their scenery. With this stuff you could have mountains covering an entire 4'x8' layout in a day, starting with a flat table. Please don't take my word for it alone, check out their website at www.bragdonent.com Once I started using this stuff I have found many ways to use it and save time and energy to actually run trains.
 

60103

Pooh Bah
Someone at the trains shows a few years ago was selling ready made foam scenery. They weren't there this year.
There is also non-expanding foam.
I tried using the expanding stuff to fill in under a window where the plaster had rotted and I needed a backing for the new plaster. When it was done, I had to carve off the stuff that stuck out, plaster the joint a bit, and wallpaper over the result.
Saw a handyman on TV using foam for insulating walls. He had an assistant with a saw carving it flat so the wallboard could go on.
 
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