I have decided on a solid plywood top to my benchwork.That is one thing i want for sure. the oher is that i want to work things in below grade as well as above.The pink/blue foam board around 2" thick would work great for me( “i think”). The problem is that it is to hard to get here and its expensive.IF i understand correctly the white foam board they sell at lowes here in 4x8 sheets is not good for this purpose. Is there a good altrnative to the ever elusive pink/blue board.
You are describing what many, if not most of us, would conclude is best done by open frame bench (and not the solid plywood you are firmly resolved to have…) and using either cardboard strip woven and glued lattice covered with some sort of hardened goop, or what I used…aluminum window screen cut to fit here and there, hot glued to the splines/roadbed sections and to the frame members as needed, and then slathered with a hardening goop.
However, I find it hard to believe that the insulation panel extruded foam is not available somewhere within 30 miles of where you live. I agree, though, it isn’t exactly cheap. Where it is used a lot, guys dumpster-dive or drive by construction and ask for waste.
Consider open joist framing, with risers from the joists to your sub-roadbed of choice, and glue strips or mesh to that with grocery bags stuffed with newspaper shoved below it to force some topography. You can make lots of dips, cuts, rises…water courses…anything you like that way. Then start mixing small quart batches of goop (three parts fine vermiculite, two parts plaster of Paris, one part Portland cement, add some masonry dye for natural tones) and spread it.
-Crandell
thank you for the advise.The reason i dont want open benchwork is that most of my plan calls for large flat areas with the exception of the roadbed itself.Most of what iwant below grade is small. sutch as dips in roads,ditches,ect.Not alot obove grade either. I am working with N scale so it dose not take mutch space to do this. I am in the Tampa area and when i ask about the foam board they just look at me funny.
I used blue foam most places. However, I also used a good deal of thick white foam for hills & mountains with good results. One of the main disadvantages of the white foam are the dangerous fumes when you melt it with a hot wire cutter. I only did limited hot wire work and used a lot of ventilation.
I covered both kinds of foam with a modified plaster/concrete mixture described by Joe Fugate. (I added a little vinegar to retard curing) This formed a hard shell. It came out much better than I thought I could ever hope to achieve. You can even fill in with crushed paper or such taped in place with masking tape, and cover with the hard shell.
The white foam is not quite as dent resistant as the blue and pink. But who cares after it has the hard shell?
Just my 2 cents
Many people in warmer climates have difficulty finding the thicker sizes of pink or blue foam. The insulation is used in colder climates not only for its insulating value but also as a vapor barrier (when the edges are properly taped). Warmer climates can benefit from the insulation, but not as much is needed, hence the availability of only the thinner material.
Try going to the Dow or Owens/Corning websites and use their locator for a supplier near you. Look here for Owens suppliers: http://insulation.owenscorning.com/homeowners/get-insulation/
Hope that helps.
Darrell, quiet…for now
I have found 1/2 inch blue foam board in 4x8 sheets at Lowe’s in Bradenton - they don’t seem to carry the thicker sheets that we would use here in Michigan. As far as the white stuff is concerned, it’s okay if you own a hot wire to cut it. If you try to shape it without a wire, it goes EVERYWHERE. Don’t ask how I know this…
Foam dose not give off toxic fumes below 450 degrees, just make sure your foam cutter is designed to stay below that as the Woodland Scenics dose.
If you haven’t started construction look into open grid bench work with risers and plywood sub roadbed covered with cork roadbed or Homabed. Then use hard shell scenery techniques. There are many varieties of the later, cardboard strips covered with red rosin paper and white glue, screen wire and plaster cloth etc. A fantastically inexpensive and very flexible means of doing scenery. Especially good for positive and negative scenery like your looking in to doing.
While not for your specific area there is still some good advise here:
http://layoutvision.com/id44.html
ratled