Hooking Light Clamps to an I beam

gmff

Member
Due to a Rooftop AC leak at the school theater we use for a yearly dance recital that trashed the floor we have to move to another school where there is no lighting system or place to hang lights.
Hanging the over the house lights I will be installing a batten on the basket ball backboard holders and hooking the lights to that and with enough cord we can make that work. The problem the stage which is usually the band and chorus room there is nothing except an I beam 18' above the floor to screw the lights to. It looks like I will need to add a piece of wood to take up the space because the clamps will not tighten down enough to tighten to the beam. If you have another recommendation I am open to that. We got bounced from our regular place on Thursday and this is the only place that we could move into quickly and easily enough to make everything work. I will be moving the strapping that is hung 9' above the floor with some 12 ga copper wiring that they stripped down from some romex. The school staples some bed sheets to the strapping so they have a background for graduation.
 
I would recommend getting some lighting trees over putting wood spacers on the bean so your clamps will accommodate.

Or

The proper clamps to fit your ibeam. Here are some clamps that might work. You didn't say what style beam you have so spec the clamps accordingly.
https://www.grainger.com/category/ecatalog/N-1z0dund
 
... It looks like I will need to add a piece of wood to take up the space because the clamps will not tighten down enough to tighten to the beam.
Don't do that!

Remove the existing lighting c-clamp and get yourself some "I-beam conduit clamp s" from any electrical supply house (not sure about Lowe's/HomeDepot though). They're not very expensive.
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https://www.lawsonproducts.com/lawson/I-beam-Conduit-Clamp-38/28658.lp

Goes as oriented on one side of the lower flange of the beam, then a 3/8" bolt goes head-down up thru the fixture's yoke. Safety around the entire beam (may take two safety cable s per instrument).

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... The school staples some bed sheets to the strapping so they have a background for graduation.
Well, that's just plain sad.:(
 
Welll, I have seen the local union use wooden blocks (1x1s cut into very short pieces) to hang lights over a very expensive Porsche at a car show... I'm not saying it was right, but I did see it from union members.

I have also done it myself, but it always feels very dirty. I will probably go out and buy myself a starter pack of those clamps.
 
Don't use wood blocks. Wood tends to compress and it can split. You're only relying on friction. I've seen it done but it is unsafe.

Lowe's and Home Depot both carry beam clamps. $6 for the large to accept your 1/2" yoke bolt. Derek linked to the smaller 3/8 variety, which would probably work fine, but I prefer the big beefy ones. An electrical supply house might be cheaper in bulk, and have more in stock at any given time. They're not designed for stage lighting, but they are designed for hanging heavy things from I-beams, often overhead, so they're certainly suitable.

The 1/2" bolts from your c-clamps may fit these, but could be too long depending on which clamps you use. Last time I installed fixtures on I-beams I think I had to buy 1/2 x 1" bolts.
 
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+1 ont he beam clamps. They are cheap. Every found-space theatre I've worked in, I'vce given them several beam clamps.

I saw one theatre that used the beam clamp, added the C-clamp do it and hung 10ft sections of pipe in ht c-clamp attached directly to the I-beams with the Beam clamp. Luckly for them their span was opn 8 ft between beams.
 
Another +1 for the beam clamps, I use the ones that take a 1/2" bolt generally and they work great.
Of course when I was younger (in highschool) I admit I had used wood blocks to get it done a number of times, but in retrospect it was a bad idea. Especially after seeing the safety go to full use once when a Fresnel got hit by scaffold (not very hard; also I did not hang that particular light nor was I moving the scaffold). The clamp just slid right off the wood (which hit the deck) and thankfully there was a safety on the fixture.
 
Due to a Rooftop AC leak at the school theater we use for a yearly dance recital that trashed the floor we have to move to another school where there is no lighting system or place to hang lights.
Hanging the over the house lights I will be installing a batten on the basket ball backboard holders and hooking the lights to that and with enough cord we can make that work. The problem the stage which is usually the band and chorus room there is nothing except an I beam 18' above the floor to screw the lights to. It looks like I will need to add a piece of wood to take up the space because the clamps will not tighten down enough to tighten to the beam. If you have another recommendation I am open to that. We got bounced from our regular place on Thursday and this is the only place that we could move into quickly and easily enough to make everything work. I will be moving the strapping that is hung 9' above the floor with some 12 ga copper wiring that they stripped down from some romex. The school staples some bed sheets to the strapping so they have a background for graduation.


I've used these in the past. They work really well for not-permanent installations. Hopefully, you can find a way to safety the lights around the I beam (or I wouldn't hang em - safety first...). Good luck!

https://www.grainger.com/product/CA...m/rp/s/is/image/Grainger/1RUY3_AS01?$smthumb$

WB
 
The other solution is Strut. A 12" or so piece of strut with a couple of beam clamp parts (many types) and you can hang whole battens or just more strut. Far more flexible than individual fixture clamps. And often cheaper!
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Welll, I have seen the local union use wooden blocks (1x1s cut into very short pieces) to hang lights over a very expensive Porsche at a car show... I'm not saying it was right, but I did see it from union members.

I have also done it myself, but it always feels very dirty. I will probably go out and buy myself a starter pack of those clamps.

Yeah...from the box pushers union. You might find better, but you wont pay more. Just because a union rigger's, neighbor's, cousin's, kid, used a wooden block, does not make it a good idea, or an informed choice.

Don't use wood blocks. Wood tends to compress and it can split. You're only relying on friction. I've seen it done but it is unsafe.

Lowe's and Home Depot both carry beam clamps. $6 for the large to accept your 1/2" yoke bolt. Derek linked to the smaller 3/8 variety, which would probably work fine, but I prefer the big beefy ones. An electrical supply house might be cheaper in bulk, and have more in stock at any given time. They're not designed for stage lighting, but they are designed for hanging heavy things from I-beams, often overhead, so they're certainly suitable.

The 1/2" bolts from your c-clamps may fit these, but could be too long depending on which clamps you use. Last time I installed fixtures on I-beams I think I had to buy 1/2 x 1" bolts.

I agree, the larger 1/2" ones are much better, bigger and wider clamping area; the smaller ones do work fine for single fixtures though, or small cable pick and such.
 
Yeah...from the box pushers union. You might find better, but you wont pay more. Just because a union rigger's, neighbor's, cousin's, kid, used a wooden block, does not make it a good idea, or an informed choice.

I never said it was a good idea. And when I did it, I was super careful to make sure there were no splits in the wood.

In my experience, IA 'employees' tend to do crazy, unsafe things just because they know they can get away with it. It's one of the reason's I've been avoiding the union.
 
I never said it was a good idea. And when I did it, I was super careful to make sure there were no splits in the wood.

In my experience, IA 'employees' tend to do crazy, unsafe things just because they know they can get away with it. It's one of the reason's I've been avoiding the union.

I'm not judging you. You saw it done with the wooden block, did it yourself, then decided beam clamps would be better. Fair enough. As far as some locals go, I don't know if its that they can "get away with things" or that they just don't know any better. Don't get me wrong, there are certainly some very qualified union hands out there, but they are often overshadowed by the boneheaded ones.
 
I never said it was a good idea. And when I did it, I was super careful to make sure there were no splits in the wood.

In my experience, IA 'employees' tend to do crazy, unsafe things just because they know they can get away with it. It's one of the reason's I've been avoiding the union.

Depends on the 'IA employees', the venue, and what they typically do. By a LOT. There are IA guys that do it RIGHT, and there are IA guys who really don't know what they are even doing. It runs the spectrum.
 
Depends on the 'IA employees', the venue, and what they typically do. By a LOT. There are IA guys that do it RIGHT, and there are IA guys who really don't know what they are even doing. It runs the spectrum.

I'm sure it does. But in my experience, I've found IA members to be rude and arrogant, and want no part of it, in this particular Local.
 
I'm sure it does. But in my experience, I've found IA members to be rude and arrogant, and want no part of it, in this particular Local.
Some call it nepotism, we call it tradition.
Toodleoo!
Ron Hebbard
Retired from IBEW 105, IATSE 129 and IATSE 357.
"You may find better but you'll never spend more!"
(I can feel the flames of Hell licking me now.)
 
I learned my lesson with the wood block hack ... even without splitting, they slip. One nonprofit venue I support has unistrut hanging from threaded rod, with blockfilled clamps and ancient instruments. Step 1 was safety cable, which have saved people and instruments a few times. Still $ raising for real schedule pipe.

Wonder - how many Fresnel drops a safety cable can sustain before it needs replacement?
 

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