# See-Through Flooring



## OnWithTheShow (Feb 6, 2004)

Anyone know what thickness of Lexan should be used to ensure a safe surface that can be walked on?


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## TheatreTechie (Feb 6, 2004)

OnWithTheShow said:


> Anyone know what thickness of Lexan should be used to ensure a safe surface that can be walked on?



It depends on you framing below. From my understanding if you build proper platforms you should be able to use the same thickness as the plywood or osb that you would use. If you give us more specifics we might be able to give you a better answer.

For one show we have a piece 4'x4' and it was strong enough for the actors.
A couple images from the show, Godspell.




Hope this helps.


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## wolf825 (Feb 6, 2004)

OnWithTheShow said:


> Anyone know what thickness of Lexan should be used to ensure a safe surface that can be walked on?



When working on the show Who Wants To Be A Millionaire, I can tell ya the clear flooring is a bit over 3 inches thick, and shaped in 3' long framed sections that are wedge shaped for the "spokes". The SIZE of your panels however will make the difference for thickness, support and framing--as physics tells you a 8'x8' section 2" thick piece will not support in the middle what a 3'x3' section of 2" thick will support, so your support frame and overall size of the panel will also matter greatly. This can best be done by finding the size of panels you need and consult your local dealer with your load needs--and for general safety you will want to do at least 8 times the support weight. So if you need to support a 150lb actor singly, you will want a panel that will support 8 times that body weight. Never get a thickness that will be only supportive of the wieght of the actor or a tad bit more--you need to consider physics of the size of the panel--the bigger the panel seize is between supports the less weight the center will support, and that a second person added, or if the actor should jump, dance or bounce, will increase the load and shock/flex the panel will need to be able to handle. As I recall, most safety load ratios for equipment is 3:1 minimum, while for people they are at least 8:1.. If you have multiple actors on this panel at one time--you have bigger calculations to consider, smaller frames of panels, and much more support. I would make your estimates and sizes, and consult your local dealer for a safe thickness--they have charts that they work with all the time.
That is to do it safely....


-wolf


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## OnWithTheShow (Feb 6, 2004)

Well I was think of something along the lines of 2"x4" or steel framing in standard 4'x8' platform style to create 4'x4' sections. Anyone know the safety tolerances for Lexan in an application like this?


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## wolf825 (Feb 7, 2004)

OnWithTheShow said:


> Well I was think of something along the lines of 2"x4" or steel framing in standard 4'x8' platform style to create 4'x4' sections. Anyone know the safety tolerances for Lexan in an application like this?



Hiya, 
GE (the maker of Lexan) has online calculators for these applications to help you figure out thickness and decide on their products to suit your need. Click on the link below, scroll down to click on Engineering calculators..you will want the "stiffness calculator" if I remember correctly to find thickness. Its been a while since I last used them.

For theater applications, Suggest you make it about 90degrees for temperature (under hot lights or heat--you can get stretch and give with some polymers that will make them more pliable which you do not want to happen), and your deflection (the amount of "give" under weight) ifI remember should be 0.5 inch to 1inch max. 

http://www.geplastics.com/resins/


-wolf


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