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How fast can I drop a hemp in


blinddog

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Hi

I want to drop a cloth in quickly, so that it looks almost as though it has fallen. It's lightweight, on a hemp. The bar does not need to actually hit the deck. I want to avoid using a kabuki. Can anyone advise if it is possible to manually achieve that speed without causing the line to jump?

Thank you!

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There is no answer. The weight of bar, weight of cloth, size of cloth, air resistance, friction in the system, gauge of rope and whether you get rope burns all make a difference and you need to suck it and see.

 

Why no kabuki and why the speed? This is intriguing.

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There is no answer. The weight of bar, weight of cloth, size of cloth, air resistance, friction in the system, gauge of rope and whether you get rope burns all make a difference and you need to suck it and see.

 

Why no kabuki and why the speed? This is intriguing.

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Thanks Kerry,

If I could get access to a stage to play around I would, but in the meantime I’m just asking around, if anyone has tried this before.

I don’t want a kabuki because they fail. A good fly man is way more dependable and responsive. Several other reasons as well...

 

Most the guys I’ve talked to have said that just letting the bar free fall might cause the line to jump the block, but I’ve not found anyone who has tried to intentionally do just a really quick drop in.

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Not a flyman but a cautionary tale. I crewed a panto once and had to fly in one set of silks during a set change with the curtains open. Worked a treat at rehearsals but once an audience was in, the air moving from auditorium onstage sent them sailing behind the set.

 

I tried it fast, I tried it slow, I tried it so slow that snails raced past but I couldn't get the bloody things down in front of the set. So they took the job off me and gave it to one of the house regulars

 

Not only did he nearly topple the set over in furious frustration he solved the problem of the silks by tearing them to pieces. Even the most experienced cannot answer your question beyond, try it. If it is purely hypothetical I doubt anyone can help as there are far too many variables.

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There is a reason for not dropping kit to the floor in an uncontrolled way.....it is dangerous!What happens if someone is in the wrong place at the wrong time, what happens to the kit that is being dropped, what happens when a rope gets caught round something and brings the system to a dynamic stop, if the kit is corrrectly installed why would the line jump the block (rope keeps keep it in place) etc etc?

I don't know which kabuki system you have used in the past, they are designed to be reliable and user friendly, cheap to hire (from Flints for example) or reasonable to buy.The dynamic forces exerted by a barrel in free fall could be very high. my advice us find an alternative method to achieve the same result

.

 

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As others have said it depends...

 

It's a long time since I was a flyman, but that's what I started as in a hemp house. I vaguely remember a shipwreck/storm scene where the sails had to come crashing down. As they were quite lightweight, they could be held by one flyman and released, with the in dead being securely cleated off on the lower rail. We only dropped them about 3 or 4 metres and they couldn't hit the stage. I think we tied off the different lines at different lengths so the sails all ended at jaunty angles.

 

Initially we had concerns about the ropes jumping off top pulleys, but in practice this didn't happen to us. What did happen however was a gentle rain of dust, confetti from last years panto, fag butts and assorted rubbish drifting down throughout the next scene as the shock load on the grid dislodged all sorts of rubbish!

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What did happen however was a gentle rain of dust, confetti from last years panto, fag butts and assorted rubbish drifting down throughout the next scene as the shock load on the grid dislodged all sorts of rubbish!

 

Having just done a fair bit of rewiring at local churh hall I can well imaging the sort of stuff you're describing, including too much where I started with 'what the f...'

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Many years ago we had a new director/designer putting on "Electra", with a "set" consisting of 2 timber squares, 24' & (IIRC) 16', angled towards each other & covered in fuller's earth (to create the dusty plains of Attica, or wherever). After 3 weeks there was more fuller's earth on the grid than the stage, & we were still finding pools of it years later. The show has stayed in my mind for another reason, as I had to create a sunrise, fader-by-fader, on a (very) manual board, over 15 minutes, before the first actor appeared.
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Love this anecdote, thanks. Yeah this is exactly the kind of thing I was hoping to do...sans the fag butts...Thanks for the insight!

As others have said it depends...

 

It's a long time since I was a flyman, but that's what I started as in a hemp house. I vaguely remember a shipwreck/storm scene where the sails had to come crashing down. As they were quite lightweight, they could be held by one flyman and released, with the in dead being securely cleated off on the lower rail. We only dropped them about 3 or 4 metres and they couldn't hit the stage. I think we tied off the different lines at different lengths so the sails all ended at jaunty angles.

 

Initially we had concerns about the ropes jumping off top pulleys, but in practice this didn't happen to us. What did happen however was a gentle rain of dust, confetti from last years panto, fag butts and assorted rubbish drifting down throughout the next scene as the shock load on the grid dislodged all sorts of rubbish!

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It is worth noting that rigging kit (ropes, pulleys, shackles, cleats, tie off points) is designed to be predominantly used in a controlled manner with relatively steady forces predominantly but enough tollerance to be able to cope with occasional excessive shock loads. If it is your intention to be "dropping" then if nothing else you will be dramatically shortening the lifespan of your kit and possibly putting existing items way over their rated use resulting in failure during the show as you will be putting several years of stress on them in a single rehearsal session. In circus there's a distinct difference between kit used for static loads and for tumbling/jerking performers for exactly this reason. If you are really determined to not use kabuki systems then at the very least you should look at installing a set of pulleys (attached to inspected points) and ropes specifically for this project so that ultimately you are only risking £50 worth of "disposable" rigging kit and not potentially triggering thousands of pounds repair to the building flys.
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Thanks, Imagineer Tom. I appreciate your thoughts. Perhaps I did not articulate what I'm after. I think xllx (above) understood what I was at. I don't want to actually let the thing freefall. Automated systems allow folks to measure the rate of speed, whereas there doesn't seem to be anyone out there who has measured an average rate of speed or range of speeds for a manual system. I was asking for a range of experience out there as to how fast folks have dropped in a hemp line, not whether its a good idea to simply let go of the rope.

 

It is worth noting that rigging kit (ropes, pulleys, shackles, cleats, tie off points) is designed to be predominantly used in a controlled manner with relatively steady forces predominantly but enough tollerance to be able to cope with occasional excessive shock loads. If it is your intention to be "dropping" then if nothing else you will be dramatically shortening the lifespan of your kit and possibly putting existing items way over their rated use resulting in failure during the show as you will be putting several years of stress on them in a single rehearsal session. In circus there's a distinct difference between kit used for static loads and for tumbling/jerking performers for exactly this reason. If you are really determined to not use kabuki systems then at the very least you should look at installing a set of pulleys (attached to inspected points) and ropes specifically for this project so that ultimately you are only risking £50 worth of "disposable" rigging kit and not potentially triggering thousands of pounds repair to the building flys.

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The point still stands though - hemp lines are normally flown in a fairly controlled manner and quite a specific way; As soon as you start using something "faster" than normal (and remember, the faster it flys in the "sharper" the stop will be) you will be putting stresses on that are outside the normal ones.
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Whatever you hope or guess, have you any proof that the arresting mechanism will be able to stop the bar in the position that you want from the travelling speed that you want. Have you any specification for the fly system stating what deceleration (g force) a single bar can give you and how accurately you can place that deceleration.

 

What happens if the bar doesn't stop as planned and comes below head height?

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