Box boom base weight ratio

DuckJordan

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I had heard of a mythical table of weights to heights that USITT had produced, However after much searching I haven't found said formula and am looking at getting some manufactured for our space, I'd like to make them mobile and free standing but I want to also make sure they aren't going to tip over.

Anyone have a link to that table or maybe the PDF?
 

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Senior Team
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It falls well within the standard but that doesn't really help my question of what the weight of the base should be compared to its height.
Depends on where the fixtures are... how fare out they are from the pipe.... etc. I've never seen this chart either. In my book, I always put at least 100#, usually 150# hanging on the opposite side that the lights hang on.
 

techieman33

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topeka, ks
I've also never heard of a specific table. There are way to many variable to make it into something that simple.

My take is to make the base light enough that one person can pick it up and move it by themselves. The Altman bases are around 60lbs. From there make it easy to add more weight and keep it stable on the base. One design that I've like has had posts with the same spacing as their arbors so they could put their stage weights on them and not have to worry about them getting knocked off.
 

gafftapegreenia

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At a certain height base weight no longer matters and the boom needs to be secured rigidly from the top as well, not just safetied off.
 
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Amiers

Renting to Corporate One Fixture at a Time.
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Phoenix, Az
Just do all the maths of everything on it. But gaff is right after a certain height it just becomes top heavy and you gotta drop a line from the grid and screw in the floor.

I would go no higher than 10ft with your boom and add the proper weight to counter what’s up in the air.
 
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kicknargel

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Denver, CO
In the interest of clarity (and not pedantry I hope): "box boom" is a front of house lighting position, just downstage of the proscenium, in the general vicinity of the box seating. Sometimes literally a boom in a seating box, other times built on the wall of the house, etc. What's being discussed in this thread is just a "boom," or a "lighting boom," or "boom and base." As far as I know.
 

danTt

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NY
At a certain height base weight no longer matters and the boom needs to be secured rigidly from the top as well, not just safetied off.
Yes and no. If restriciting to "standard" schedule 40 pipe attached to a base I certainly agree. That doesn't prevent engineering truss booms/rovers of various sizes that will be fine as ground supported--Look at a tower crane as an extreme example.

If I were to have some booms manufactured I'd probably look at rolling dance towers/truss builds if they fit in the venue and budget, they are certainly easier to move around and stabler.
 
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RonHebbard

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Waterdown, ON, CA
I had heard of a mythical table of weights to heights that USITT had produced, However after much searching I haven't found said formula and am looking at getting some manufactured for our space, I'd like to make them mobile and free standing but I want to also make sure they aren't going to tip over.

Anyone have a link to that table or maybe the PDF?
@DuckJordan and @techieman33 Control Booth's search function dredged up this this thread from six months ago when we last thrashed this topic into submission.
https://www.controlbooth.com/threads/side-lighting-solutions.44740/#post-390192
Toodleoo!
Ron Hebbard
 
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DuckJordan

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It's not quiet what I'm looking for however, very helpful. These would be semi permanent positions on our third floor box positions. Slight modification to traditional setup. Think a vertical ladder with a built in side ladder. These are close to a 40' drop so trying to figure best way to build the base to either A come close with weight ratio, or B design it to concrete anchor to the floor.
 

RonHebbard

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It's not quiet what I'm looking for however, very helpful. These would be semi permanent positions on our third floor box positions. Slight modification to traditional setup. Think a vertical ladder with a built in side ladder. These are close to a 40' drop so trying to figure best way to build the base to either A come close with weight ratio, or B design it to concrete anchor to the floor.
@DuckJordan Back in the latter 1970's The Stratford Shakespearean Festival had one box boom position based in their first box on both sides (SR and SL) of their Avon theatre venue; the upright was 1.5" ID Schedule 40 and it was chock full of 6" ellipsoidals and a sprinkling of Fresnels with boom arms sprouting in three directions for its entire height. The Festival operated in a rotating rep'. Once a given production's set and blocking were decreed set in stone, gobos were photo etched with each ellipsoidal's shutter patterns, the gobos crimped into their holders, the holders color coded for a specific production and tied to a specific fixture with short lengths of tie line. Flame resistant cardboard gel frames were similarly color coded with their cuts and split cuts stapled in. At every elevation an open topped wooden "mail box" was U-bolted to the rear of the boom's vertical to safely store all of the color frames for a given elevation.
The problem was access and dealing with ladders in the limited confines of the box seating space. Two of us finessed a way to secure a 20' length of an aluminum extension ladder to the boom using sleeves around the boom with angle iron welded to the sleeves and bolted to the ladders. On the bottom of the ladders we had one caster on a horizontal length of I-beam spanning across the bottom of the ladder to support it vertically. On the vertical member of each ladder furthest out from the boom we affixed an adjustable brake with a rubber foot to spread its pressure across a few square inches of the box seating's carpeted floor. This allowed one tech' to ascend the ladder to the top and remain at that elevation while an assistant rotated the ladder approximately 150 degrees around the boom. Having changed all gobos and gels at a given elevation, the tech' on top would descend a couple of rungs and the other tech' would rotate the ladder in the opposite direction. Down another couple of rungs and roll around. Down another couple and around again. Repeat as necessary until at the base of the boom. The bottom of each boom was locked with a cup pointed Allan set screw in a heavy duty Kee Klamp floor flange lagged into lead lag anchors drilled into the poured concrete floor. Having all of the shutters fully opened with photo-etched custom gobos, meant the booms could be re-gelled and focused in full work light with zero need to light the fixtures and with zero need to wait for a previous set to be struck and replaced with the next set scheduled in rep'. Worked like a time and effort saving charm, was a little rough on the carpeting but I believe a layer of rubber matting was soon added. At three or four elevations up each boom they were bracketed off the face of the proscenium with lag screws in lead lag anchors drilled into the face of the prosc'
Toodleoo!
Ron Hebbard
 
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JonCarter

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Weld up some ladders out of 1-1/2" sch 40 pipe, as large as will fit the space, with 8" x 8" x 1/4" plates on the top & bottom of the verticals. Bolt these plates to the floor and whatever is structural in the ceiling and don't worry about counterweights.
 

danTt

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NY
Weld up some ladders out of 1-1/2" sch 40 pipe, as large as will fit the space, with 8" x 8" x 1/4" plates on the top & bottom of the verticals. Bolt these plates to the floor and whatever is structural in the ceiling and don't worry about counterweights.
I certainly don't want to see 70' tall ladders any time soon.
 
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RonHebbard

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I certainly don't want to see 70' tall ladders any time soon.
@danTt We have at least two venues in my area with grids substantially higher than 100' above their decks; from memory, 104' and 120' plus more than ample head clearance above their grids. Centre In The Square in Kitchener Waterloo, Ontario has an elevator barely big enough for two persons running from USL to grid level with stops for their fly floor and loading floors; they also have a straight ship's ladder adjacent to it as a back up. Many hands ride up and climb down. In downtown Toronto, The Four Seasons Opera and Ballet venue has a much larger elevator in parallel with a standard enclosed stairwell wide enough for at least three people abreast all the way to grid level. Seventy feet would be a short ladder in many of our area venues.
Toodleoo!
Ron Hebbard
 
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DuckJordan

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So we ARE talking about box booms! I agree with others; for this I would prefer a structurally integrated solution that does not rely on ballast weight.
I would prefer that as well but I have to offer multiple solutions not a single plan. I'll be urging to bolt into the floor and secure to the catwalk above but may get some kick back due to the facility being owned by the city but managed by a private corp.