Swing

[gunner]

Hi Guys,

 

For this years panto the director/writer has requested a swing as part of the set. I have had a quick search, but have only found garden swings. What I am really looking for is something that I can rig to the grid (a bit like these (http://www.covent-garden.co.uk/Theatres/images/matilda7.png) . Does anyone know where I might be able to source one from.

 

Thanks

 

Dave

[ImagineerTom]

It's really not as easy as you'd think it is. You're going to have to get something custom made (or heavily modify an existing item) and the rigging is no-where near as simple as you'd expect. The swings in matilda literally cost thousands of pounds and several days work to get looking that effortless. That's not to say it's impossible but there's so many complications that make it a pain in the ass to do.

[J Pearce]

Assuming the swing has to be sat upon, rather than just set dressing It will probably be easier to get a freestanding swing and screw it to the deck or a heavy steeldeck riser.

 

The loads imposed by a swing are obviously dynamic and quite complex to understand, and unless you have a very low grid attaching it direct to the grid would result in a very long chain/rope meaning it wouldn't swing right and would swing very slowly (simple harmonic motion, A level physics etc).

 

Circus and aerial performers are probably the people to speak to, but expect to have to add lots of extra bracing and other gubbins to get it to work safely.

[trussmonkey]

you could look at a modified trapeze. these have rope (fibre or steel wire or both) as the vertical suspension points. these are terminated in an eye at the top. would be very easy to rig using rated spansets/slings etc assuming you were happy with the motion of the swing.

 

for trapezes do a search on google and you will come up with some manufacturers who might be willing to do a custom one for you.

 

you wont have significant vertical dynamic loads if you are only sitting on the swing and not performing tricks. you will have to brace the fly bar it is rigged to very well to prevent lateral movement. and you will have to take into account the lateral forces on anything the vertical ropes touch. if you go to in between fly bars to the grid you will still have to pay careful attention to the bars as the swing moves.

[kitlane]

Many moons ago I created a couple of simple simulations of a swing to show my students

 

The first is a swing attached to a fixed beam (such as a very sturdily braced fly bar)

 

http://youtu.be/sXuBgzHRlQY

 

The second is the same swing attached to the same bar but with no bracing to the bar.

 

http://youtu.be/Nl07cLM-wkc

[Andrew Edwards]

Nice little animations BUT to clarify for the uninitiated, a double pendulum shown in the second video produces a completely random and unpredictable motion. That's before we even get into lateral movement.

 

Have a quick look for double pendulum on YT and enjoy an interesting distraction. It always reminds me of the 80s kids show 'The Lowdown' only without the lasers.

 

Oooh now then, a double pendulum with a laser on the end... :D

[gunner]

I think Jon has probably come up with the easiest/best solution if I can convince other people that a conventional swing attached to a steel deck would be the easiest way forward. I may know someone who has contact with circus performers and to be honest it wash't something I had thought about until suggested here. With regards to the rigging element, I have got a rigger who is willing to have a look at what is or isn't possible, but even if we can sort that element out, the actual swing itself is the one item I have as yet been unable to source. Thanks everyone for your input and I will try and keep this updated to let you know what happens.

 

Dave