# Standard practice or dumber than dirt?



## JChenault (Aug 7, 2010)

I was dragooned by my wife into doing a show at a local high school. In general I am not impressed by the installation. Lots of dumb, over-designed things.

IE the traveler track rope is SL- the SM console is SR. The house light controls are so complex that they cannot be fully used. The fixtures from front of house which should be 19 or 26 degree are 36 degree units. Lighting circuits that are miss connected. Some dimmers randomly blink off, etc.

One item that seems problematic is the rigging of the electrics. The system is under-hung and the stage house looks to be 50 feet tall ( I expect to avoid a fire curtain). Single purchase counterweight system with a minimal pit for the arbors ( about 8 inches ). The electrics will come into the deck ( and when at the deck the arbor is well positioned to the single loading rail). but they will not go all the way out. IE there is a hard stop on the counterweight tracks about six feet off the deck to stop the electric from going further out.

Looking at the install, it appears that the stop was installed to stop the cable cradles ( two per electric) from hitting the ceiling. The cradles are not attached to the primary lift cable. IE there are two extra cables from the arbor to move the two cable cradles. There seems to be lots of slack in the cable when the electrics are all the way in. 

My question - is this the 'way it is usually done' these days? It seems wrong to me, but I am wondering what others have seen. What are the generally accepted ways to rig the cradle so it moves at the proper speed ( IE slower) than the batten?

Note - this question is for idle curiosity only. I have no authority or responsibility for this venue, and have no plan to try to fix anything.


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## sstolnack (Aug 7, 2010)

Was this by chance Roosevelt High school? It sure sounds like it. Traveller rope, SM box, confusing house lights, etc, and I see you're from Seattle. I don't know anything about the rigging though, I just do lights. I don't know anything about mis-wired circuts or blinking dimmers though, so maybe not roosevelt?


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## JChenault (Aug 7, 2010)

sstolnack said:


> Was this by chance Roosevelt High school? It sure sounds like it. Traveller rope, SM box, confusing house lights, etc, and I see you're from Seattle. I don't know anything about the rigging though, I just do lights. I don't know anything about mis-wired circuts or blinking dimmers though, so maybe not roosevelt?


 
Nope - this is West Seattle. I have seen three recent Seattle area theaters with the same consultant and installer. Sounds like Roosevelt may be number four


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## Sony (Aug 7, 2010)

NNHS's cable cradles were built similarly, except the cradles move at the same speed of the electric and only have ONE extra lift line per electric. They were however built to stop much lower then all the other battens so the cradle does not crash into the loft block, like you said, they stop about 8ft lower than all of the other battens.


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## sstolnack (Aug 7, 2010)

Ok, yeah, it seems most high schools are built interestingly. I've seen some other threads about that here. The traveller rope however makes sense for our system because it's on the side of the rail, so the riggers can open the traveller during shows. At least that's how we do it, I dunno if it's done differently elsewhere.


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## MPowers (Aug 8, 2010)

Just thinking about the rigging.... and the electrics. Are these line sets permanently dedicated electrics? If so, why would one ever need to fly them to the grid? Electrics usually trim about 4' or so above the bottom of the borders at trim. One does not usually, in my experience, light shows from the grid height. It sounds, from your description, that the electrics will fly to a storage height above show height, just not all the way to the grid. If limiting their travel about 6' or so results in simpler or less complicated rigging, and subsequent lower installation costs, why not? If the line sets were to be converted to scenic use, uninstalling the cable picks and removing the short stops would be simple and cheap as opposed to rigging the cable picks to allow full flight. 

All the above is just IMHO and judging from the description of the space without specs, or dimensions or other information. On site inspection might or might not change my view point.


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## JChenault (Aug 8, 2010)

MPowers said:


> Just thinking about the rigging.... and the electrics. Are these line sets permanently dedicated electrics? If so, why would one ever need to fly them to the grid?



Well - try this scenario. I have some platforms on stage that preclude the third electric from coming in to the floor. I can't put weight on the arbor because I have to bring it in to the floor to access it from the loading rail. I have to bull it out, and then climb on a ladder up 8 feet or so to put weights on the arbor. If I could take the arbor to the floor, I could simply do that and then add weight.

It's not so much flying the pipe to the grid as it is getting the arbor to the floor. ( which is the same thing)


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## Sony (Aug 8, 2010)

Do you not have a mid-rail?


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## MPowers (Aug 8, 2010)

John, Are the platforms show specific or always there like permanent choir risers? If they are permanent, then the rigging should have been installed to accommodate. However if they are show specific, then the loading situation is, unfortunately, a situation that has to be dealt with on a show by show basis. Because the travel of the arbor is known, and the design of the show is known to restrict loading at the loading rail, the TD, LD and ME should get together early and figure out the conflicts. The LD should then do a preliminary plot for the problem pipes and hang, cable and balance them before the platforms or other set pieces are in place. That way the weight balance is already taken care of. If one or two units need to be added or removed, that's only about 30 lbs. max, not much weight to move or change. In a 50' high house, the transfer of lift line weight (depending on the # of lift lines) can approach or exceed that each time the batten runs in or out. Another solution is to make the platforms or other scenic units movable even if they don't have to move for the show. When I worked at Meadow Brook, a LORT house in Michigan, The electrics were dead hung and the only access was by lift, so on platform shows we designed and built the platforms to roll and move to allow lift access for focus and maintenance. Even though your electrics can fly, a similar approach might be in order. Because the arbors are at a good loading height when the batten is at floor working height, the cable pics are rigged so they can not be fouled, pulled or forgotten, the design seems to be if not fail safe, at least Idiot Resistant. In a high school situation as much prior planning as possible should be done to reduce or eliminate the need to bull unbalanced lines in or out and to absolutely eliminate loading weights from a ladder. 

BTW, having the cable pic on their own lift line is a GOOD practice. I have seen far too many installations where the cable pics are on the short and/or long line lift lines, pulling them out of plumb and that too stops the battens from going to the grid except now the cable attachment can jamb in the loft block if the operator is not careful or stops are not put in the arbor track, right back to where your are now. Far too many theatres have them installed on hand lines and they forget to loosen them when the batten flies in, (I've seen bent pipes due to this) or forget to pull them out at the time the batten is raised and the multi cables get tangled in the ends of the battens.


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## derekleffew (Aug 8, 2010)

MPowers said:


> ... the design seems to be if not fail safe, at least Idiot Resistant. ...


I like that, Michael. Can I use it?

I agree that the SM Panel, Fly Rail, and all operating lines should be on the same side of the stage, but I've been in many houses where that wasn't the case. It's (relatively) easy to re-rig a traveller track to reverse the live and dead ends. That hardest part may be relocating or adding a new "floor block socket plate" on the other side (if so equipped. I prefer a weighted floor block).


Image from H&H Specialties.pdf.


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## Footer (Aug 8, 2010)

Thats the way cable cradles should be done. Limiting the travel of the arbor is the second part that every install that does cable cradles in this way should do. I have seen installs where the cable cradles can smash up into the grid. Its not a pretty thing. That extra 6' of clearance is not a deal breaker for me vs. having two or three swags of cable come crashing to the deck. If you must grid the electric completely, it is possible to remove the hard stops and have someone on the grid guide the cradle through the grid openings.


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## JChenault (Aug 9, 2010)

Reading the responses, I don't think I was clear in my original question. Let me restate.

Is there any valid reason that a properly installed single purchase electric has to have a stop on the arbor track so the arbor will not come to the floor when the cable cradles are on their own line? 

It seems to me that you would have to rig the cable cradle so it moves more slowly than the lift line which would incur some additional costs. If that analysis is correct, how would you rig this, how much would it have added to the cost. If you were designing a theatre what would you specify to get full travel on the arbor?


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## derekleffew (Aug 9, 2010)

From JR Clancy: Cable Management for Lighting Battens | iSquint.net :

> Read more on the JR Clancy Rigging Report
> 
> If you need an electrical cable management system over the stage there are several options listed in ascending order of cost magnitude.
> 
> ...


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