Hi all,
I’ve decided to use pink extruded foam to make a mountain with ten portals in O gauge.
It will be large.
I am looking for tips on working with the foam, especially the best glue to layer it, cutting it, painting it… and perhaps some resources for portals, or portal molds… I could also scratch build some portals…
Thanks in advance
Your best bet for cutting the foam is the hot foam cutter. Cutting it with a knife leaves jagged torn edges. I use the foam board glue in the caulk gun canister. It takes awhile for it to completely dry though. Another handy tool is a wood rasp so you can shape the contours of the mountain. The tunnel portals can also be cut out with the hot foam cutting tool.
This is your decision, but I’m sort of old school and believe that extruded foam leaves a bigger mess than using plaster cloth to build mountains. I have both on my layout and have found the plaster cloth makes for better mountains.
I take large pieces of cardboard (like those found for refrigerator or washing machine containers) and cut them into long 2" strips. I then weave them together in the shape of an upside down basket stapling the ends to the plywood and using hot glue and clothes pins to hold the pieces of cardboard together where they cross one another to form the mountain. I then cover the whole thing with plaster cloth. Finally, i’ll work in about an 8" x 8" area and slap some plaster on the wetted plaster cloth and just before it sets, i’ll take a a painter’s putty knife and cut and gouge the rock formations into the plaster.
It’s also messy, but in my opinion, not as messy as all those little blue or pink pieces of foam everywhere is…chuck
Hey Kyle
I use and like foam but I also use Sculptamold with it. Sculptamold is cheaper than lightweight Hydracal. For glue I just went to Lowes or Home depot and bought caulking gun tubes that are listed, for foam.
I use the 2 1/2" and 1/2" foam board which I stack either horizontal or vertically to get my basic shape. There is no need to make the mountain solid foam. For tools I like a long flexible very sharp fillet knife to flake out rock like designs. For some things an electric kitchen knife works well. ( don’t get caught doing this) [:-^] I know there are hot knives (wire) that work well also.
I paint the foam with interior house paint all one color and then work with the different hues of craft paint. I’m no expert but this seems to work for me.
Best of luck
Lee
PS. wiping the foam with a damp cloth kills all the static foam cling. A sawing motion with a very sharp knife leaves a slick smooth rock like finish.
This thread http://cs.trains.com/trccs/forums/t/171611.aspx over on the Layouts and Layout Building forum has an interesting technique for cutting tunnels through solid foam bases.
Remember to allow for access to your tunnels. Trains will derail in there. It’s not a matter of if, just a matter of when. For that reason alone, a hollow-frame mountain is often more practical than a solid foam mountain.
For my layout, I needed tunnel portals that were smaller and thinner than those available from Woodland Scenics, etc. I bought one portal, and then used latex rubber to make a mold. From that, I was able to cast my own portals to my requirements. They came out very well. Since you have a lot of portals, though, you should consider a variety of different portals to add visual interest. As a railroad added more tunnels through the years, they would have used different techniques anyway, so having too many identical portals would not really be prototypical.
Hi,
check out this video series on youtube http://www.youtube.com/watch?v=y2_yQoalTWk&feature=fvw .
Hope it helps
Frank
I’ve used foam and plaster cloth to make mountains. When I’m using foam to build a mountain that has tunnels in it, I stack strips of foam; just wide enough to stack on top of the strip below. And, I ALWAYS leave access to any track under the layout. I used common bead-board to make fillers that fit snugly between the benchwork. When something happens in the tunnel, I can roll underneath on my crawler, pull out the access board, fix the problem, then reinsert the board. What I find that helps is to glue a small rectangle of bead-board to the bottom side of the filler pieces; it works as a handle, so I don’t have to pry it out. To glue my foam and bead-board, I only use acrylic latex caulk; it holds well and it’s foam friendly.
I read your post and the responses you received with great interest since I hope to begin construction on a new On30 pike soon, and plan to use a similar technique. All posts were good things to think about. Thanks. I have only one thing to add. Someone, in some magazine, (Maybe Jim H in MR) taped a wet/dry vac to the handle of a Stanley Sur-form tool and claimed it helped eliminate the mess. Haven’t tried it but plan to unless somebody here tells me it is a waste of Duct Tape. Thanks again
Cheap latex caulk works well for an adhesive. Cut and snap for basic form of peices, then shape. To help keep down the mess I have used a cheap anti-static spray with success. Yes, you will have cleanup to do if you saw it. If you use a hot knife or hot wire tool, be sure to have good ventilation, it does give off fumes, which some folks have had problems with.
Good luck,
Forgot to answer part of your question. For paint many folks use a cheap latex paint in an earth tone. You can often find something close on the OOps shelf. I have read that some even thin it some before painting. Many put sculptamold, plaster cloth, gypsolite or some such over the surface to add texture before painting. If you are going to use a lot of ground cover (forrest floors, etc) just paint the surface, it holds paint quite well.
As for the portals, you can cut foam with a hot knife to the shape you want and you will have a smooth surface. If you want a stone look, you can scribe lines into the foam using a ball point pen tip or similarly pointed object. Give it a try, very little expense if you goof a time or two.
Since you are working in O scale, you might give a try over on the Classic Toy Trains portion of the forums and see if anyone there has made something similar in your scale.
Good luck,
Thanks all, the project begins
EK