Lift Help

[tziola]

Hello Everyone--

I'm working on a show idea, and we're in need of a simple lift for a few props.. The lift probably needs to be capable of around 200-300 pounds, but definitely not more.... I drew this picture in paint to explain the simplicity of what I'm thinking.

Thanks!!

 

[MPowers]

Can you be a bit more specific as to what you need?

Is this in view of the audience when it happens? How fast does it need to move? What are the objects being lifted and how are they to be attached to the lifting dvice? Do they simply fly up and out of sight? do they appear being lowered to the stage and the talent removes the rigging and uses them? Is the facility a stage or gym or warehouse or....?

 

[tziola]

Can you be a bit more specific as to what you need?

Is this in view of the audience when it happens? How fast does it need to move? What are the objects being lifted and how are they to be attached to the lifting dvice? Do they simply fly up and out of sight? do they appear being lowered to the stage and the talent removes the rigging and uses them? Is the facility a stage or gym or warehouse or....?

Yes it's in view of the audience, and it doesn't need to move too terribly fast.. There will be a variety of objects attached to it, mainly made of PVC pipe and wrapped in fabrics with dancers using the fabrics. It's going to occur during a halftime show at a football game, over a track. I was thinking we could build an X frame, each of the four ends in the ground with the cross being where the motor is. It only needs to lift 150lbs, not 200-300. The talent would not be leaving the ground, simply putting some of their weight onto a hanging prop.

 

[MPowers]

I'm sorry, I will have to drop out of this thread. If a person is going to put any of their weight on the rig at any time, it becomes performer flying or aerial performance and that is not something that can be advised on line or long distance, only if I am on site as a (the) rigger. When the performer puts their weight on a rig, it may well experience a temporary dynamic loading several times their body weight, in several directions, not just vertically downward. And, while it may seem minor, an awkward or out of balance fall of only a few feet, less than the performers height even, can seriously injure someone or worse if they hit their head or twist their neck on impact.

 

[tziola]

I'm sorry, I will have to drop out of this thread. If a person is going to put any of their weight on the rig at any time, it becomes performer flying or aerial performance and that is not something that can be advised on line or long distance, only if I am on site as a (the) rigger. When the performer puts their weight on a rig, it may well experience a temporary dynamic loading several times their body weight, in several directions, not just vertically downward. And, while it may seem minor, an awkward or out of balance fall of only a few feet, less than the performers height even, can seriously injure someone or worse if they hit their head or twist their neck on impact.

Thanks. It sounds like we might be in over our heads a little with this one. We're going to have to rethink it.

 

[FatherMurphy]

You didn't mention the intended size of the X, but rigid trussing tends to be rather weak over long spans, and force vectors are a concern with horizontal cable methods of rigging things. The short version is, anything substantial enough to hold your hoist will probably be too substantial to have next to a playing field (in case a player collides with it), or will be too big to easily set up during halftime.

Perhaps your props could be held aloft on a pole supported from below? (Although the pole itself can present a hazard, if dropped on a performer's head)

 

[tziola]

You didn't mention the intended size of the X, but rigid trussing tends to be rather weak over long spans, and force vectors are a concern with horizontal cable methods of rigging things. The short version is, anything substantial enough to hold your hoist will probably be too substantial to have next to a playing field (in case a player collides with it), or will be too big to easily set up during halftime.

Perhaps your props could be held aloft on a pole supported from below? (Although the pole itself can present a hazard, if dropped on a performer's head)

We thought about that... or we thought about the structure idea, with a manual pulley set-up. We've reached the conclusion that no weight is to be put on it and that feet will not be leaving the ground unless a performer jumps.

 

[What Rigger?]

Good thinking. I'd further encourage you to make sure that whatever is to be flown/suspended/lifted be given a minimum standard of a 5:1 design factor, and that all your pulleys and ropes are made for overhead lifting. Just to save time: what's sold at Home Depot, Lowe's, etc...is NOT generally rated for that function. So save time and don't go there.

 

[tziola]

I should note that this is a high school production, student produced (I being one), with student talent!

Thanks!

 

[What Rigger?]

I would also encourage you to NOT do this at all if you have no prior rigging experience.