Making walls fold down...

[superdoo]

I am trying figure out a way to make walls fall towards the audience so that they can become decking and reveal scenery behind them. I was initially thinking of using counterweights and a pulley system underneath the platforms. I may also be helpful to note that this at an outdoor theatre and there is no fly system and I start construction on a bare stage. I usually use 1/4 inch ply to face the walls and 3/4 inch ply for the decking.

I could go on with more details, but I am hoping for any advice at all.

[soundman]

Broadway style flats will float down on a nice cushion of air all by themselves. They will create a nice puff of dust which will be pushed into the house which might not be such a great idea though. Plus once you add some 3/4 ply for decking the weight might be too great to do safely and smoothly.

If you were able to get a few decent sized air cylinders you could rig them up to act as resistance brakes by puting a regulator on what would be the input as the stroke is extending and then mount them to the wall of flats.

Ive attached a quick and dirty sketch of what I think it could look like. You would have to cut a slit in the decking as well as come up with a way to hide the cylinder. Both of which are doable. The anchor point for the cylinder will have to be butch as it will be taking a load alot (150% to 200% not in the mood to do the math) greater than the weight of the flat because it will get side loaded.

[jwl868]

Is it feasible to just attach the panels to the floor with hinges, and then have stage crew members bring them down one by one, after detaching and removing the braces?


The face of the wall on the floor may pick up dirt or otherwise get marred from the floor. That may be a secondary consideration.

Joe

[Footer]

I would probably to it as a hinged counterweight, draw bridge style. You will have to build it all fairy stout, basicly building the walls as you would a standard deck. Few questions, are the walls on a raised platform/do you have access to the underside of the deck that the walls will be sitting on? Can you weld? To make sure this thing won't blow apart when its in the down position, you will have to build it out of steel. Let us know those two important things, then we might be able to help. I would try to stay away from anything mechanical supporting this load, it could easily get away from you.

[bobgaggle]

How tall are the walls? Are they perpendicular to your center line? If you have a curved wall of flats it'll be impossible for them to fall flat.

I may be adding more problems, but how are you going to support the wall before it falls? you can't very well push over a flat with 45 degree braces on the back of it.

This idea would work well if you had access to under the stage, but it can work above stage too: You can attach a line to the top of the flat and run it at an angle through the deck of the stage, on the upstage side of the flat. (it would look like a giant triangle from the side) below you can have some sort of apparatus that will slacken the line, gravity pulls the flat down. You could even have a few stagehands manually letting out the line, (might be a bit dangerous) Once the flats are down, you can wait till the next blackout to untie the lines from the flats/new deck, and pull them through to under the stage.

[superdoo]

In regards to footers comment about welding, the answer is no I can not and don't believe I would have access to someone who could. For extra bracing I was thinking of bolting in angle iron (or something of the sort) to the 2x4 frame in key areas of stress.

I am going to have access to the underside of the "main" deck. I have to add 2.5 foot platforms in the lowest area so the audience (do to a slowly rising hill that makes up the house) can see.
I would like the walls to be 8 feet tall but they could go as low as 7. They will be flat as I am not the greatest carpenter and my staff consists mostly of teenage girls that are in the show!
I like soundman's approach, but then I believe I run into the same problem as my counterweights/pulley system gave me. When the wall is down I need people power to get it back up and assuming I went with pulleys and cable under the platforms, wouldn't the weight needed to counter the walls weight change with the angle of the wall?

[thelightingmancan]

What is your budget for this show?
If you had some money, you can use a pheumatic actuator, which uses air pressure to turn with a huge amount of torque. You can run the air lines outside, and have someone relieve pressure and let the flat down, you then add pressure to raise it back up.

A simpler way to rig it is to join 2 4x4's together on each side to form a long plank making something that resembles ski's. You then attach (with a hinge) a 2x4 on the back of the flat, or the deck face so when the deck is down it forms a big triangle with the wire running from the fornt of the deck to the top of the 2x4 to the back of the 4x4's to the back of the deck. You put the winch at the back of the deck and you will get great leverage to lift and lower the deck. With the hinge on the 2x4, you can put extra wire on the winch and let the 2x4 down, leaving nothing behind it. You could also make a device to let the cable slide along to fold the 2x4 without much extra cabling, but you would have to raise the 2x4 in order to winch the deck up back to a flat. I'll post a sketchup design when I get to my computer.

[Radman]

How much vertical space is there under the deck, and is it free of obstructions? I'll try to make a quick worksheet to clarify my twisted idea...

[thelightingmancan]

Here is my thoughts CB Help.jpg

[superdoo]

David, the show is of course on an extremely limited budget (what show isn't). I like your idea of using 4x4's as posts and I think I could make it work. Would you mind explaining how I get get the posts to drop in greater detail?

But for arguments sake.... I'm still contemplating my original idea of pulleys running under the stage and counterweights behind it.
The problem now is that the upright wall has no weight to be countered and as it becomes more parallel with the stage its weight increases.
How would I go about designing a "variable counterweight" so to speak?