I have three catwalks in my black box that run parallel to one another. They are fantastic to hang from, but there are no hang positions (
grid or otherwise) between the catwalks, which leads to inadequate focus positions. What I'm hoping to do is to run a standard
batten pipe across those spans (about 12 feet) and attach them with cheeseboroughs (burgers? idk). The span doesn't SEEM long enough to cause any sag (and we're not going to exceed 50-75 lbs per pipe), but I want to check with the hive mind and make sure I'm doing this correctly. I'm not at work this weekend, but can provide a photo to better explain my idea. If there are any additional
safety precautions that I should be aware of, such as secondary methods of securing the pipe in addition to the clamps, OR if there are better methods than what I'm currently thinking of, any advice is greatly appreciated.
Thanks all!
@stolympiakos Don't misconstrue me as any manor of authority having jurisdiction in your, or any other, area.
Having said that, you're describing a method that's been used in the Hamilton Place Studio
Theatre black box space since its construction in 1973 and hasn't failed
yet. The studio is approximately a 75' x 75' black box with a
flat (non-raked) patron's balcony approximately 8' wide within the 75' on all four sides leaving a span between opposite balcony rails of approximately 49 or 50'. From the
flat floor surface of the balcony there are four permanently installed (Welded in place) ladders, one in each corner, leading up approximately another 8' to an overhead
system of parallel catwalks criss-crossing the room in both directions. All of these parallel catwalks have 1.5" Schedule 40
iron handrails of two heights on both sides. Typically designers
yoke work lights out from the upper
hand rails and a myriad of other front lights, down lights, back lights and specials from a combination of the lower
hand rails and standard
boom arms up to 24" from the lower
hand rails and any / all supporting verticals. In spite of the many positions and angles already available, it was less than a year before designers were doing exactly what you're proposing with approximately 12' lengths of 1.5" Schedule 40
iron (Never aluminum) pipe bridging across the gaps between handrails. Normally everything was kept in compression with the added pipes bearing down upon the supporting rails using a mixture of three types of clamps: Kee (Brand), Cheeseburroughs (Sp?) Roto-loks. [Not to be confused with coffin locks]
I
WON'T tell you I personally observed pipes added in compression and secured only with cotton tie-lines and / or
duct tape.
No, you won't see me putting that in print. (If you think I just did you're surely imagining things.)
As to loads; In 1973 the originally supplied inventory was 20
Strand Pattern 223 eight inch 1 Kw fresnels and 20 Century
Strand 6 x 9 500
Watt 'chimney-top' ellipsoidals with a dozen or so Century
Strand scoops. Designers were always borrowing more fixtures from the Hamilton Place Great
Hall main
stage inventory and in less than two years revenue from the studio space was purchasing more and more fixtures.
Here's another one of those things you'll never see me writing here.
12' spans of 1.5" Schedule 40
iron pipe often had six or eight ellipsoidals hung from them and occasionally ten or twelve yoked up, out and down.
I'd
like to tell you every
fixture was secured with its own
safety.
I will admit to seeing one
safety looped over a pipe and serving two adjacent fixtures.
I will
DEFINITELY state this was in a time LONG prior to 'wigglers' and fixtures in excess of 30 pounds each.
@stolympiakos Optimistically I've answered your query.
Toodleoo!
Ron Hebbard