Question on using foam

[jimh]

I have never really used any type of foam in my layouts unless it was some store bought piece. When I landscape something it is usually out of a plaster based paper mache type stuff.

Anyway there is a lot of different kinds of foam products out there from styrofoam, to the insulation board type, to the type you often use to replace a seat cushion with. So what type of foam do like to use to landscape with?

 

[jbaakko]

Insulation type. "Dow Board" is a easy pick, its smoother, not like the bubbly stuff you get when you buy a new TV, or computer. It cuts easy and leaves little mess.

However, if you're living in an area like me (San Diego) and you ask for Insulation foam at a home improvement store, they usually reply "Is that what its used for?" then point you to the bubbly stuff.

 

[jimh]

ROFLMAO.........I can only imagine.

Living in the midwest we have more types of insulation products than a person knows what to do with.

 

[MT Hopper]

Hi! I use Dow Cornings 2" extruded insulation foam ( usually coloured Blue but also comes in Pink). It is fairly easy to use. Most folks seem to use a serrated edged bread knife to cut it. If you use a jig-saw then I would recommend a smooth edged blade be used as it reduces the dust. The extruded foam is readily glued togethjer by using water/latex type adhesives. Liquid Nails or PL 300 Construction adhesive in a caulking tube are the ones I have used. My favourite tool for cutting and shaping the foam is a "Hot Wire" tool. I am currently using 1" X 2" "L" girder framing with "supports" underneath every 16" as in a stud wall. My foam is inset into this framing and so far I haven't glued it in as I am considering experimenting in a fashion with Ian Rices' jigsaw module concept.

RAFLMO

Cheers Will

 

[Gary S.]

I used the 2" dow blue foam and I love the stuff. It cam make a mess though, especially if you use a wire brush to do the shaping. But, keep the shop vac handy and it ain't so bad. The best thing about foam versus plywood is it is so easy to cut in ditches and features that are below the tracks.

The question of California and insulation foam... I seem to remember discussing here on the gauge that the blue and pink stuff was banned in california.

 

[MT Hopper]

Oh boy! If you can't use extruded foam then you really can't use foam!The only alternatives are white bead board or florists green foam neither of which has any real mechanical strength. The only other "foam" I can think of is the very expensive high density foam they use in display work. The operative phrase with the latter being "very expensive". Anyone else know of a "California" foam? - other than the surf that is.

Cheers

Will

 

[MasonJar]

Extruded (blue or pink) is best where strength is also required in addition to form. But the "traditional" white beaded styrofoam can be used for building up landforms over some suitably built strong benchwork. Dave Frary had an article in MR some time ago about using this type with the cans of expanding foam to make "Arizona desert" type scenery.

Andrew

 

[jimh]

I really appreciate the tips.

As far as my bench work goes the table top is a 3/4 inch plywood with a 3/4 particle board over that. That sits on top of a 2X6 frame set 24 inch on center. The legs are also 2X6. I can walk on the thing and it does not bow, wiggle or jiggle, and I am 240 lb. LOL

Rest assured though I am certainly filing away all of this info for future reference, as well as any more that comes my way.

 

[MT Hopper]

Hi. I would agree that white beadboard is used for land forms. I don't recall the MR article ( Mason do you have an issue date for the MR article?) but I would suspect that Frary covered the beadboard with something like celluclay or one of the types of plaster. I have never done this myself. My question is ..... If you use white bead board and a covering material such as plaster or celluclay, then, must the covering material be applied in a thick layer in order to give the trunk pin or whatever, of a model tree, something to be mechanically secured to?
I ask this as I have a concern there would be no ability to resist laterally applied forces.

 

[MasonJar]

I think the Frary article is mid-1990's (I want to say 1996), but the index of magazines at Model Railroader should be able to pinpoint it for you.

IIRC, Frary used chunks of white styrofoam glued together with the expanding foam to form the base for the landform, much as cardboard strips are (were ) laid over crumpled newspaper for support. Where you would have (maybe) removed the newpaper after the plaster cloth hardened over the cardboard, with foam, you just let it stay.

Even with a pin in the trunk of your trees, you would still need glue to secure it, and some sort of landscaping to blend it into the ground.

Andrew

 

[rhtastro]

J, I concur with MT Hopper with using the hotwire for shaping and his use of Liquid Nails latex glue for gluing. Also, I have found that the denser foam found at art stores, Michaels for example, works much better than any found at a home improvement store. I used the 2" foam and it can be found in white or green. With the green you have instant grass. I found that using latex paints works well for covering without disolving the foam. See my corrent thread "pics of Equity Junction" for views of the finished product using this foam. Have fun, that's the reason we do this, I think.
PS. I see that there is some discussion of the availability of foam in CA, not the sea type from the ocean. My local Home Depot has several types and art stores as above have more. Of course, you do have to pay for it. We use a lot of it every winter to insulate all those Canadians who seem to live here for long periods every year. We try to protect them from the sun as much as possible. But they're nice people and the best of visitors.

 

[jimh]

I had a little time today so I went to a local Home Depot and took a look at the foam insulation board. I have seen and used it before, but always looked at it through the eyes of carpenter and not through those of a modeler. I certainly can see why many of you tout the advantages of it.

I have seen the foam boards and other similar products sold at hobby supplies and while I am sure they would work very nicely, the price is not very compatible for a MRR on a somewhat limited budget, not to mention the fact the closest hobby store to me is about 60 miles away.

Thanks to Wally World we no longer have any local hobby shops, or fabric stores, or craft stores. Of course now that they have destroyed all the local competition they no longer carry squat when it comes to craft materials.