Large Rings

[Marius]

Howdy,
For my next show the designer wants several macrame type hanging peices consisting of a cone of ropes tied around the circumference of a ring, and then more ropes hanging from the ring to the floor that can be moved around by the actors. Most of these are hula hoop sized, and that is what I'll be using for the ring part. Two of them, however, must be very large. 8' and
14' to be precise, and I am at a loss on how to make such a large ring. I thought about aluminum conduit and a pipe bender, but if I did my math right the 14 footer has a 43' circumference. Do any of you incredibly smart and clever folks have any suggestions?

Thanks,
Rick

[derekleffew]

I think you're on the right track thinking of EMT (which is usually coated mild steel, not aluminum.) This site may help. What thickness do you desire the rings? Anything larger than 1" requires special, expensive, machinery. Would a 12'-8 7/8" diameter work instead of the 14' (as that's 4 x 10' lengths)?

I would see if anyone knew an electrician, or call an electrical company and job it out to them. They can probably get better prices on materials than you can, and will certainly do a better job, as conduit bending is a craft requiring many years of practice to perfect. I'm guessing your largest ring would cost you $20-50, depending on the stock size and whether or not they had it leftover from a previous job. Keep the screws on the connectors to the inside of the circle, cover them with knots and they won't even be noticed.

The above is for decorative, non-weight supporting rings only. If you want structural (and expensive) contact Tomcat or another truss manufacturer, who would be glad to build whatever you like from 50mm aluminum alloy stock. Arrow Dynamics bent some 12" pipe stock for a certain project here in Las Vegas, and you don't want to know what that cost! (I didn't know they went bankrupt, but it wasn't due to the Las Vegas job.)

Edit: Just read your profile. It appears you're a teacher, so your first call should be to Facilities. Either there's an electrician already on campus, or they have a preferred electrical contractor who would be willing to do you a "favor," for a six-pack of appropriate non-alcoholic beverage. I don't generally offer this advice, but: "go hang out around a construction site." Outside the fence, of course.

[jwl868]

You might also be able to make a large diameter hoop with polyethylene pipe that is used for natural gas lines and drinking water, too. (This type of pipe is made in a continuous length, rather than 10' lengths.) The pipe is small diameter (I think an inch or so). I've used it for a 6-foot hoop to support an oversized "hoop-skirt". I'm not certain if will work for a 14-foot diameter hoop, though. That is, I'm not sure if it will stay rigid enough to support the hoop shape.

Joe

[Marius]

Two great ideas. Many thanks. And the only thing the rings have to support is ropes hanging from them.

[Van]

I've used JWL's idea before and it works great. The black poly pipe can be picked up at any home improvement store and there are even double ended connectors availible so you can stick the ends together. EMT will work pretty well also. you can bend it easily with a conduit bender or build your own table top pipe/tube bender. I'll draw a picture of one I built just for futre reference, it may not come in handy on this project but you never know what the future holds.

[avkid]

Is this poly pipe you're referring to also called Pex?

[Van]

I'm not sure of the Brand name. It's about 1" 1 1/4" OD about 3/16" wall thickness usually used to install Sprinkler systems in yards/gardens.

< hope this doesn't double post I got a "can't display page" error the first time I tried to submit.>

[Marius]

Originally Posted by Van

I've used JWL's idea before and it works great. The black poly pipe can be picked up at any home improvement store and there are even double ended connectors availible so you can stick the ends together. EMT will work pretty well also. you can bend it easily with a conduit bender or build your own table top pipe/tube bender. I'll draw a picture of one I built just for futre reference, it may not come in handy on this project but you never know what the future holds.

What's driving me nuts about this is I remember way back when I worked at the Burt Reynolds Dinner Theater we had this groovy hand-cranked pipe bender, but I can't for the life of me remember what the darned thing looked like!

[soundman]

SOmethign like this? http://www.tnfab.com/rolx_bender.htm

[jwl868]

Originally Posted by avkid

Is this poly pipe you're referring to also called Pex?

PEX is cross-linked polyethylene. The PEX is very similar to, but not identical to, the polyethylene (PE) pipe that I was thinking of.

Joe