im in the process of laying down the foam base on top of plywood on my layout. whats the best way to hide the gaps in the foam? ive concidered usingsculptamold, but ive never used it before.
Thanks
btw, great railfan day today. after seeing P&W in old saybrook and NECR in new london, i accidantly caught P&W heading north in the norwich branch. i have to thank mom for that one, she didnt feel like cooking, so we got fish and chips and headed down to the river, and i thought there was now way my luck would hold out…i also saw it crossing the thames river bridge as i was watching the NECR.
GEARHEAD426
I use spray-foam in a can, the stuff for filling gaps in windows,etc. Use the one that expands the least. “Great Stuff” in the red can works good. I use it to fill in voids and to help shape hills, etc. It’s easy to carve with the break-away razor knives. Don’t try to fill more than 2’’ voids at a time or you’ll end end up with big air bubbles. Wait at least 48 hours before trimming and shaping. To finish it off, I use a thinned vinyl spackling brushed on and blended into the pink/blue styrofoam. Vinyl Spackling is best for use with foam as it stays flexible and is less likely to crack or break off if bumped.
If you are going to top coat the foam with some form of ground goop, use that. I use lightweight premixed drywall seam cement for everything. It will fill gaps nicely, though the expanding foam sounds interesting. I mix it with paint and saw dust for my version of goop.
Interesting idea with the expanding foam goop - I’d never considered that one. I usually try and sculptamold across the gaps.
I cover all my scenery with scultamold. It adheres very well to foam,Its controllable. Paintable,sandable, carvable and has a lovely dried oatmeal like texture when dry that looks alot like natural soil. I find it works better with a spatula of some sort, I use an art spatula. The worst problem with it is one has to be careful not to plug up the sink with the paticles of the stuff. If I’m going to do a lot I get a 5 Gal. bucket and fill it half or more with water and use that to clean up with , then throw the waste down the toilet which can handle that kind of waste. Its all water soluble so don’t worry about pollution.
I usually use Sculptamold or plaster to blend rock castings into a foam base. But if I am creating something with a smooth slope (like just a hillside to be covered with ground cover) I fill the gaps with cheap acrylic caulk.
I spread it along the seam, then dip my finger in water to smooth it in. I use an old margarine tub (one of the big ones) half full of water to rinse my finger off. A paper towel is handy also to clean up. You can get a perfectly smooth coverage this way very quickly. The foam and caulk gets a coat of paint, then glue, then ground cover in repeating layers.
I have also built up some of my foam scenery so that it fits into an area of the layout, then finished the scenery on the workbench. After I place it on the layout (supported by risers just like track) I fill the seam with caulk. When dry it gets paint, glue, dirt, grass, ground cover, whatever.
My two cents - it works for me anyway.
George V.
Here’s an example of how we built mountains at Dunham Studios. My co-worker Zoe, used all the scraps around the shop for this one. The yellow foam is spray foam in a can. I don’t remember what we used for “snow” on that job.
not dial-up-friendly:
http://www.villagephotos.com/pubbrowse.asp?folder_id=1717626
this Lionel layout was built for the Valley Junction R.R. Museum (Lionel) in Des Moines. BTW, the viaduct in the 3rd photo was also made of blue styrofoam!
Since I don’t use any plaster on my foam layouts, I fill large gaps with Great Stuff, and small gaps with latex caulk (the same stuff I use to lay track). In a few areas, I’ve actually “kept” the gaps by sculpting them into depressions and stream courses.
Zoe appears well outfitted for the job!