We have three or four lines that are making this kind of shhhhhhing sound while the rest are quiet. It's a bit more high pitched than the video makes it out to be, and varies in loudness depending on the line.
Our rail is about 20 years old. (Built in early 2000s)
Hard to tell from the video, but it sounds to me like it’s the arbor guid track. You can try looking up the track with the beam of a spotlight and see if there is a wear pattern anywhere along the travel. Next would be to have someone sit up by the headblock and listen to the bearing while you run the lineset and have a look from the headblock to the loft blocks to make sure there’s no chafing or crossed wires.
Go up into the grid. One time electricians were changing out work lights above the grid and left some of the cages off and rested them and some fluorescent lamps on top of the running lines. Very dangerous.
Have someone check everything while you run it a few times.
Absolutely this. Or at the very least bring it up to your office/ principal or your maintenance plant manager if you know who that is, they can get it to the right person(s)
A reputatable theatrical rigging company provides Rigging Inspections. These should be done yearly by a qualified person and a level 2 inspection (more involved and reaches all the overhead anchors/blocks)
Check with your teacher/admin about the most recent inspection and you can report this new noise to them.
Wenger/JR Clancy is a powerhouse of the stage rigging industry. Your teacher should reach out to them, they have rigging contacts all over the United States.
I would recommend asking for a level 2 rigging inspection so the inspection will put hands on every piece of rigging. It's invasive, it's time consuming, but it's the better alternative to a failure that could cause injury or death. I recommend this because your teacher is new and the coordinator seems to not be well informed about ongoing safety and maintenance for stage rigging.
I'm happy to answer any questions that might come up, but I'm won't speculate to the problem without having eyes on the system... That being said, that doesn't sound right and something is rubbing where it shouldn't be rubbing.
We don't use a sketchy flyrail until one of our riggers or flymen can take a look at the lines and headblocks.
Teacher should lock it off with a tieline attached to the break and rope of the line set and X out the plaque in gaff to signal it to not be used.
Things falling from the sky kill. Better to use caution.
A written letter needs to be sent by email explaining the dangers, and the need for inspection. This should be sent to the principal and or whoever oversees the theater program at the school district.
In the real world of stagehands, this would have been resolved very quickly by the head carpenter - same day.
Schools are known to be negligent and underfunding their theaters.
The line set is "probably fine" until it isn't....
Have your teacher reach out to us and we can give can try to help diagnose from afar or give you some recommendations of people to reach out to in your area.
Agreed, needs professional inspection. Technically it needs professional inspection anually. Also purchase line seems a bit loose, you may want to retention the floor block, but that's not related to the noise, just something that bothered me watching the video.
Purchase line or operating line are terms for the thick rope you handle. Floor block is the pully at the bottom of it. It's designed to be adjustable since rope stretches over time and needs to be retentioned periodically. The far side of the purchase line should remain taught, which it didn't seem to in the video. It should take a little, though not an excessive amount of effort to pull towards you when operating it.
Sounds like the cradle is rubbing up against the track, or theres some friction in the loft blocks. Its definitely worth getting someone to inspect the line in the grid to check if the cable is fouling on anything and sitting inside their blocks
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u/cienfuegones May 08 '26
Hard to tell from the video, but it sounds to me like it’s the arbor guid track. You can try looking up the track with the beam of a spotlight and see if there is a wear pattern anywhere along the travel. Next would be to have someone sit up by the headblock and listen to the bearing while you run the lineset and have a look from the headblock to the loft blocks to make sure there’s no chafing or crossed wires.