I use plaster of paris and cut up bed sheets to add 'land' to my layout. This is put over hot glued cardboard strips. The problem I have with plaster, is it sets up rather quickly. So today, by accident I tried joint compound.
I was cleaning out some old cans of this-n-that when I found a small container of joint compound. It had been sitting so long that the compound had turned to sort of clay. Wondering if I could save it, I mixed a small amount with water. The mixture was like a thick soup, the same consistancy I use for plaster. Hmmm. I wonder how this would work as scenery? I cut a small piece of bed sheet, dunked it in and applied it to a section of my layout that was waiting for 'land'. It worked fine. But the best part was that it didn't set up very fast. Actually it is rather slow. Lots of working time and what was in the mixing container didn't get hard. I managed to get a small section done.
I wasn't planning on doing this today so the layout wasn't properly cleaned off.
But dilutted joint compound works just fine with a long working time.
I believe the joint compound is not as strong as plaster. Which may or may not be a problem. That close to the aisle, I predict a problem.
I used a pre-mix type spread over foam and it developed visible cracks which were a royal pain to fix. I also used a dry powder version mixed with water that didn't. The stuff is a dream to work with, as it's very soft (see first sentence). And, yes, has a long work time.
If I were doing paper-towel-dipped-in-glup, I'd use plaster or maybe hydrocal for the glup. If I needed to follow up with more glup, I'd consider joint compound.
Ed
I used it too for the "concrete" and paved areas. As Ed mentioned, the powdered seems to work better. You can get with different "set" times.
Penn, the cut up sheet thing is a new one on me!
Mike.
My You Tube
I use 'plaster wrap' to build up my scenery - quite fast and economical if you buy rolls off the Internet.
I 'paint' the plaster wraplease with joint compound. What I have purchased comes in 18 lb bags, and you mix it with water. You can get anywhere from 20 minute to 90 minute setup time. I usually buy the 45 minute setup bags. It 'paints' on and one has enough working time so it does not set up in my mixing bowl.
Modeling BNSF and Milwaukee Road in SW Wisconsin
In my opinion, joint compound isn't an especially good choice for scenery: it's too soft to stand up to any use and will re-soften (to it's pre-application state) when it gets wet. In thick applications, it will crack as it sets.Instead, I used Durabond 90 patching plaster. It comes in several versions, with the number suffix representing, in-minutes, its approximate setting time.It can be mixed to pretty-well any consistency needed, and will still set in the proscribed time, and can be applied as thickly or thinly as needed, without fear of cracking. It's extremely durable (who'da thunk it?) and cheaper than most hobby products, such as hydrocal.
I use it, over aluminum window screen, for landforms...
...and atop plywood, like this....
...to create "water"...
...and in homemade styrene moulds to make bridge piers and abutments...
Wayne
I have used joint compound for river beds. It spreads easily and sets up slower. It also sands easily. I seal it with Gesso Surface Prep before painting and adding water products.
It will shrink and crack if applied too thickly though, so not sure how it would be for land formations?
tim
Joint compound or mud is all I use, applyed to foam land forms, sometimes with the aid of fiberglass mesh tape. Easy to apply, can be worked with a wet brush,carved, colored with any water base paint.When done, just put cover back on tub. I had some sit around for at least 7yrs,still good. Sure beats mixing, messing, and clean up.
I tryed to water it down and use paper towels, it works but I found that useing the mesh tape is faster and less mess.
I have not had issues with becomeing soft again, (unless I want it to) or not being hard enuff
IMO D90 dryes too hard and heavy
Wow, looks like i'm a little behind on the joint compound and other materials.
Mike, I have been using bed sheets for a very long time. They hold together no matter how wet they get, form fit to almost any terrain, and drys hard. A single twin size flat sheet covers alot of area. If you decide to try a sheet, wash it first if it is a new sheet. It will hold the water/plaster better.