# Conversion from Standard Platform to Stress Skins.



## wemeck (Oct 2, 2003)

Back in the late 90's I worked at a summer stock company that was adding stress skin platforms to replace traditional theatrical platforms. Here at GBS we still use traditional theatrical platform extensively and I was wondering what you all think about stress skins. How many of you are using stress skins and/or traditional platforns?

More Info about stress platforms @:
http://hstech.org/howto/carpentr/plats/platfrms.htm


----------



## ship (Oct 3, 2003)

stagecraft just had a large discussion on it. I love stressed skins in concept myself but have never had the chance. For legs, it might be necessary to make the legs have a top piece of plywood and supports that attach to the leg as it's own unit. Than just screw in the plate to the stressed skin. If you put the leg plates so that they will support more than one platform at a time, all the easier to install. I think I would make some "X" shaped legs with sway brace or even some say 12" cross section legs out of at least laminated 1.1/4" ply with a top and bottom plate so you don't have to do any sway bracing if under 30". Than have a top and bottom plate perpendicular to the X shape that's well attached with nailer blocks of cross grained lumber instead of plywood end grain. That way you can screw the as it were colums to both the plat and the floor. After that height, you would probably need further sway bracing.

Otherwise, there is the truss method. Simply put, long frames of leg as if stud walls or hard flats that are sway braced between them that screw into the stress skin bottoms. That way if your stage were a bit uneven you would not have to worry about shiming the platforms. It's a normal alternative legging platform method that would work well.

How you face such platforms without damaging them might be a good question. Since it's only end-grain plywood and foam to attach to, what you drive into the plywood could become difficult unless you put nailers at the edges of the stress skin counter sunk into the foam. That might work. Perhaps two nailers per platform if 1x stock. Or perhaps if you want to get really complex you could also mount coffin locks to the interior sides of the stress skin and lock them together as per a normal platform. Could be interesting.

On the stress skins themselves. Getting such things professionally made would be a good idea for the maximum strength. Otherwise, you would be best served by doing some industrial contact cement and weighting the things until dry. But in making them, if there is a problem, that's a large liability factor. But least that way you would not be stuck with I think wafer board lumber as per a normal stress skinned panel. A 7-ply ACX or Poplar for the tops might be good enough that you don't also have to masonite or what ever stagecraft currently recommends - them for the top. You can also get 7-Ply poplar in 5' square sheets. Might be possible to get away with 5-Ply 1/2" plywood for the bottoms of the stress skins - but that's an engineering question. Cold be interesting on the 5' platforms f you want to get even more radicle yet. 30" centers for the legs should be fine and lend a whole new world to platforming.


----------

