I got some brand-name "Gypsolite" from Scenic Express in the past, and really liked it for scenery hardshell. But it's pricey. I went to Home Depot and found this stuff:
"USG Sheetrock Lightweight pre-mixed joint compound" Comes in drying time versions of 20 min, 45 min, 1hr plus.
...that seems to be the same thing as Gypsolite, just the Scenic Express container did not list ingredients, so I can't be sure. Same stuff, different name? Just wanted to see if anyone used this as a substitute, or whether anyone knows if it is virtually the same or if there are any downsides to using it. I really liked the texture of the Scenic Express stuff, and want to be sure that the HD stuff has that.
The ingredients for this stuff start out the same as Gypsolite as I know it...gypsum and perlite. But this sheetrock compound also contains mica and a silicone compound.
I've never used Gypsolite from Scenic Express, but dry wall mud will crack as it dries if it is put on too thick. Anything over about 1/8 inch thickness will crack, so you need to apply it in thin layers and allow it to dry before adding more if you have any areas that need to be filled in.
My personal favorite for scenery is 20 minute casting plaster, but it comes only in a 120 pound bag. We use it at our club.
True gysolite and structolite are very different from joint compound. They are for use as brown coat plaster and contain perlite "grit" for texture and weight reduction. You can find one or the other at any real lumber yard, at least in the northeast. 25 pound bag goes a long way and is cheap.
The USG joint compound is for use with sheetrock (drywall sheets) and does not have the same texture. It's meant to be sanded perfectly smooth. Plus it cannot be applied thickly or it takes forever to dry and it WILL crack. Great stuff for finishing the walls and ceiling but not for scenic landforms. Joint compound comes in pails (I think that USG is green, blue or purple lettering depending on dry time). Structolite comes dry in a bag (similar to cement).
I'm surprised that the borg store doesn't carry the good stuff.
Anyway good luck finding what you need.
The mind is like a parachute. It works better when it's open.
I found what may be the same thing, its smooth set compound for drywall. It also came in 20-40-60 minute types. I used the 40 and am happy with the results, although I did mix it with paint, water, and vermeculite for some texture. I put this mixture over a plaster cloth shell to add strength and give me something to drill hole for trees and such.
I think you will be ok with it. Shoot some guys even add cement to the mixture.
I like the Structolite brand from my Home Depot. As mentioned, this is a brown base coat plaster that contains grit for good texture. It is also extremely slow setting (hours) so you have all the time in the world to work it.
spidge wrote: I found what may be the same thing, its smooth set compound for drywall. It also came in 20-40-60 minute types. I used the 40 and am happy with the results, although I did mix it with paint, water, and vermeculite for some texture. I put this mixture over a plaster cloth shell to add strength and give me something to drill hole for trees and such.I think you will be ok with it. Shoot some guys even add cement to the mixture.
I'm not sure if the product you refer to is the same used at my club in place of plaster. We use the USG Durabond (brown bag 45, 60 and 90 min) not to be confused with the Sheetrock white bag fast setting joint compound. The Durabond 90 is mixed with vermiculite or sawdust colored with powdered dyes and applied over shop towels glued to the cardboard web. This works great for very large areas and has sufficient base for drilling of trees.
A note: this area was purposely left unfinished for the last show to show the steps of scenery. Large rock cut is the Cripplebush rubber rock (Santa Fe Canyon), portal is WS, tunnel liner is cast hydrocal. We will need quite a few more trees to finish, upper distant trees are polyfiber balls to show distance and height.
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