Props falling apart on cue

[TomHoward]

Afternoon all

I am just on a bit of an appeal for ideas.

We are hoping for an effect at the end of an adaptation of Journey's End, where basically onstage is a bunker, and we are hoping that as part of the shelling some practical prop might fall apart on cue.

The only problem is that the stage is in the round, seen from all sides, and the only cast member left onstage to operate anything is dead.

 

We already have heavy sound going on and probably some plaster/dust loaded into a kabuki drop system that will scatter over the stage area for the finale.

 

I'm thinking of maybe some kind of 12V RF switch off ebay, maybe with something magnetic / solenoid or similar which will cause something to fail.

What the furniture/ set piece that falls apart is isn't too important - maybe a desk or a shelf or something falls down or apart.

[ImagineerTom]

If it's for a shortish run then I have a ready-made gizmo you can borrow - its a tray with a solenoid pin that fires out of it via RF control. If you have a glass on it then the glass will smash, if it's something less brittle then it will be knocked over - I realize it's not quite as dramatic as a sofa falling apart but the slightly more restrained effect of something smaller and delicate being impacted by the explosion could probably be more powerful than half the set collapsing?

[TomHoward]

Thanks for the offer - that sounds about right - I'm not thinking of walls falling down or anything, books off shelves or similar is about the right level.

Would you might sharing some details about how it's made - what kind of battery and what kind of RF switch & solenoid are involved?

If it's a simple arrangement I might be able to make one up with the time we have so we can have one to keep, or build it into a desk or something so items can fall off it.

 

I have some strong 12V solenoids left over from the kabuki drop system we made left over, but I guess we might want push solenoids for this.

[ImagineerTom]

It's a RF controlled solenoid from a radio controlled car stearing system which actually releases a spring loaded lever that provides the momentum to break/nudge things, all mounted in a tray - think of it as a radio controlled mouse trap.

[TomHoward]

Aah- thanks for that - thinking about it I could use the pull solenoids to release something spring loaded - there is a desk onstage so we could knock some items off the desk using something sprung down into the desk and latched with a pull solenoid. I do have some servos and an RC receiver system from a previous project if the solenoid doesn't have the power.

[Jivemaster]

Member "Cedd" is good at things that work on cue. IIRC he has a clock that falls apart on a remote signal.

[dbuckley]

One can get RF remote controls from Ali for about $20 for two transmitters and a receiver. These are intended for garage door openers, having a key-ring type transmitter, but I've used them for many things, the most recently embedding the transmitters into fake rifles so a sample is triggered to go BANG when the trigger is pulled and the bolt clicks. They have two buttons so two independent control paths. The receiver has a pair of isolated contact changeover relay outputs, and operates of 12V.

 

The receiver "learns" the identity of the transmitter(s); press a PCB button, press button on remote, LED flashes, learned. The transmitters are coded by soldering bridges between pads, so (I think) 512 different codeings possible. The receiver can be set to latch or momentary by means of a jumper.

 

Finally, order the right frequency for the country! By default they supply 315MHz for USA, but do 4xx MHz for rest of world if asked for.

[TomHoward]

Those are the kind of things I was thinking of - if we were distributing though, what we'd really want is something like one of the 4-way transmitters, and then 4 individual receivers, that we could hide around in different props.

[alistermorton]

Couple of things we did (although it wasn't in the round so might not work so well for you).

 

Around the doorways there were lots of "sandbags" which we could dislodge from behind the set and as they fell loads of dust and muck fell out. Maybe you could arrange something similar with solenoids.

 

There was a netting roof which also had dirt and muck concealed in it and this came down when the bomb went off.

 

We had radio controlled hurricane lamps around the place that went out when the bomb hit.

 

The biggest stunt was a false beam that appeared to be holding the roof up which had a single post in the middle. When the bomb went off a wire was pulled that lifted the beam off the post which was biased to fall one way and then the false beam appeared to snap and the roof fell in. This all together gave the impression of the dugout collapsing around the bed.

 

Whether you can make any of these work in the round is up to your ingenuity. There were a couple of anachronisms in the set but no one seemed to mind.

[cedd]

Member "Cedd" is good at things that work on cue. IIRC he has a clock that falls apart on a remote signal.

You called.... http://www.blue-room.org.uk/public/style_emoticons/default/biggrin.gif

 

Thanks for the recommendation! It does seem to be becoming my "thing" around these parts. I'm currently trying to suss out a Cello that plays itself.

 

The Cuckoo Clock is a fishing line triggered device, but there's no reason why it couldn't have been done by a motor. My tools of choice are remote control car servos. They're cheap, have tonnes of torque and are pretty straightforward to control. They're rubbish at doing anything quickly though (well, as quickly as you need) and I'd suggest they be used to pull pins or release catches, rather than creating any effects themselves.

 

Somebody mentioned building devices similar to mouse traps further up. I'd go one step further and actually use mouse traps! They're a great little spring engine to drive all sorts of instant effects. Chop off the treadle side of it, so you're left with just the spring and everything behind it (non-mouse side), then reverse the trigger bar so it sticks out of the back of the mouse trap (will involve moving its' mounting point) and then release this bar with a servo.

 

I just bought a Spektrum DX7S radio control system used from Sussex Model Centre by mail order. Very cheap and gives you a 7 channel radio control system. The problem is that you can only bind one receiver to the transmitter at a time. You'd have to cable your servos out from the receiver.

 

Not sure if it's any use, but here's a video of the cuckoo clock;

[Jivemaster]

http://wirelessfireworks.co.uk/firework-firing-systems.htm

http://easypyro.com/

 

Both sell radio remote untis intended for fireworks but possibly repurposable for sfx. Some are powered by 4 x AA cells so 6v. Some by a tiny 12v SLA. All have some time lag usually about 0.3 seconds, all would need some kind of relay to operate a trigger.

 

http://www.ebay.co.uk/itm/1-2-WALL-CLOCKS-Battery-Operated-Large-Big-Digits-Office-School-Kids-Furniture-/181536766477

 

Clock that could be dropped on cue by pulling the hanging nail into the wall by string wire or wireless.

[TomHoward]

I had a quick play this afternoon for an hour, and I've currently found and old-ish desk, routed a slot through the top and 'hidden' a solenoid and L-shaped piece, so the solenoid pull action underneath causes the top to kick up. It's a bit of a snatch action at the moment, it throws an empty bottle clean into the air - not quite the effect I was after directly - but with some work on the prop as well it could work.

 

Also - I may not have quite mentioned clearly enough that this in the round is part of a festival performance of 5 plays - so as well as being in the round it also needs to be self-contained, portable and can be stuck - so I'd need a receiver in each prop that has kind of thing build in. I'm thinking a couple of solenoids in the desk, the director has suggested a bookshelf (though personally I'm not certain how that works in the round - I guess it would need the back off it so the books could be seen from both sides) and perhaps something like a pillar / prop that could topple on cue.