Mid Traveler Broke again...what is the issue here, and how can we fix it

[Anonymous067]

Okay. I'm convinced the MT at my facility is cursed.

(problem #1) About a year ago, (forgive the un-technical terms to follow), the first, most center-stage, grommet got ripped out of the top of the curtain, which, is the only one that actually does any pulling work to move the curtain open/closed. Next thing I saw was the little runner in the track moving without the curtain.... I suspect what happened was somebody really hauled on the rope, when the runner actually got jammed somehow in the track (bad design??)

Our MT has always been a PITA to open/close, mainly because when flown out, the weight bag likes to spin...causing the pull ropes to get a twisted (20-30 twists usually). Then people try to pull on them without untwisting them first...

(problem #2) Last Friday, I ran a dance recital rental in the space. I used the MT as the most upstage curtain, and flew it out, and closed, at the end of the night. Now, Wednesday rolls around, and suddenly, the middle grommets have been ripped out of the curtain, in the same fashion as listed above! What!!!??? This of course creates a weird dip in the curtain, and it's natural waviness is screwed up, due to lack of support. Of course, nobody told anybody this happened, the leave it for us to find out when we need to use it again.... I walked into an in and open mid traveler, which, while still functional, doesn't look very pretty!

I pose the following questions:

How do I make the weight bag STOP SPINNING??!
How did problem #2 (the more recent one) happen?

 

[derekleffew]

First, follow this page for some nomenclature: Besteel Model 170, 171N, 171R, and 172, and attachments / #170 Besteel / Curtain Track, Curtain Hardware & Stage Fabric / Home - Alcone Corporation .

Don't have a clue as to why #2 happened, as there were apparently no witnesses. Sounds like with previous failures, the first single carrier after the master carrier jammed.

As to the weighted floor block spinning...I suspect on initial installation the operating line was removed from the spool wrong, perhaps off the end instead of un-spooled. All rope and cable has an inherent lay (twist) and should be installed in a relaxed state. I've had floor block ropes want to twist one or two times, but never as much as 30. Sadly, the only way I see to attempt to fix the issue is to remove the operating line entirely, stretch it out straight and remove any unnatural twists or kinks. If going to all the trouble it might be good to replace the line entirely. Someone else can recommend the proper rope; in my day it was braided 1/2" cotton rope with an iron core, not sure if that's still the best. Hopefully MPowers and others will steer you in the right direction.

 

[mstaylor]

Travelers can be very agrivating to keep working. I agree with derekleffew, fly it into a working height, pull the rope completely and stretch it out straight or replace it with a new rope. I would try reusing the old one first. Before bringing it in close the curtain. If the grommets are torn out and are not repairable then sew in the string or chain that attaches the curtain to the carrier. Trap one end of the rope to the main carrier, string the rope through the curtain carriers, mice, and through the down pulley. At center there should be a piece of hardware to carry the slack of the rope, go through that, bypass the slave carrier and string the other curtain. Go through the slave pulley on the other end and back to the master carrier. Attach the second end to the master carrier. Estimate the amount for the drop of rope, then attach the slave carrier to the rope.
Fly it back up to trim, weight the down pulley, and then adjust the tension at the main carrier. If you do not have a way to get to the carrier at trim then close the curtain completely, get any slack past the down pulley and tape the two ropes together just above the pulley. Fly the curtain back in, work the slack through the top pulley and either tape it or have someone hold it. Then go to the center, take all the slack through the main carrier plus little more. Take all the tape off, fly it back up and check it. That should take care of the tension and the spinning.

 

[wolf825]

Not sure...sounds like you need a visit from your local drape rigging company. It could be your mid is having dry-rot issues--give it a feel around the grommets to tell....could also be your carriers or track may have 'issues' and perhaps if its buried the chain is getting in the way and is putting a stress on the curtain itself when pulled to hang out....replacing carriers is easy to fix things like that...and if needed track can easily also be changed out.. If its difficult to track open and close or noisy it could be the carriers or track. As for the bag spinning--we have pinned, spring clipped and finally just stitched our bag strap to the upstage side of our mid curtain--it won't twist without twisting the curtain which it can't...so it always stays untwisted (and it stays nicely hidden behind the curtain and doesn't get wild and swing around etc.). You may want to give that a try... We did the pinning and clipping to test out how well it would work and last etc....before we stitched it with heavy drapery thread for perm...


-w

 

[MPowers]

There are obviously several problems here, and there may be several causes for them, so it is not possible to tell what the real problem is without actually looking at the track and curtain. It would seem that one of the problems is that continuity of personnel and communication between different crews is not as strong as it could be. I can't help with that, but I'll try to help with the equipment issues.

The rope issue is mostly as others have said, it was installed without regard to the natural "twist". Again, as others have said, remove the operating line and examine it for damage, frays or other problems. If your track has back fold hardware, make sure you check how it is installed so it may be replaced the same way. If the rope is undamaged, it may be re-installed. If there is damage, then a good cotton braid of the same diameter may be purchased from your local stage equipment company or ordered direct from ADC or H&H. For manual operation, it should not have a wire core unless the curtain is unusually large or heavy like acoustical curtains. If the curtain is, say 60 or more feet wide and 30 feet or more high, then a wire (GAC) core is necessary to limit the amount of stretch when the line is operated. The "Twist" when using a sandbag weighted tension pulley is, unfortunately, more common than not. Replacing the rope with the twist laid out and removed will help but not necessarily completely eliminate the bag twist, only a floor mounted tension pulley can do that and then you run the risk of someone flying the curtain and forgetting to un-fasten the floor pulley first.

While the rope is removed is the time to inspect the rest of the track and the curtain. Remove the curtain from the carriers. Check the webbing for brittleness, tears and other grommets that may be loose or partially torn out. If the webbing or fabric are brittle or crumbly or tear easily with just your fingers, it is time to replace the drape. If the curtain seems OK except where the leading edge grommets have been pulled out, then some sewing and new grommets are in order. first remove the grommets that have been torn out. Sew a new backing of either new webbing or several layers of canvas, not muslin, to the rear of the existing webbing for the first 12"-18". Install new grommets. If the master carriers of your track have 2 chains, put two grommets in the leading edge of the curtain the same distance apart as that chain spacing.

While the curtain is off is also the time to inspect the track and hardware. Examine all the carriers for free rolling wheels, cracks, missing chain hooks or cushions or bumpers. If the track is the "Channel" type rather than the "I" beam type, check all the channel for dust, obstructions and foreign objects. Clean as necessary. Check the track slot to make sure it has not been bent or pinched, making the slot too narrow at some point, or too wide causing the carrier wheels to bind. Check any splices to see if they have gotten out of alignment and need to be re-adjusted. If you have any idler pulleys to support the rope, check them for free and easy movement. Check both the live end (the double upright pulley at the operating end) and the dead end pulley ( the single horizontal mounted pulley at the opposite end) for free and easy operation and that the guides do not pinch or snag the rope.

Finally, when re-installing the rope, curtain, carriers etc., pull the curtain to the fully closed position and note where the off stage end is positioned. It is possible that the off stage side was tied off short and when the operator tries to fully close the drape, it pulls the curtain too tight ripping out the leading grommet. Check the last grommet and if it also shows signs of being torn out or stressed, that may be the problem. If that is part of the problem, install a drift chain on the last grommet and attached to the tie off point on the track. The drift chain should be similar weight to the trim chains on the carriers, and just long enough to allow the curtain to close without stress or stretch on the curtain. Along this same line, if the curtain overlaps more than 24", reset the stops at the center to restrict the travel.

I hope some of this solves your problem with the curtain and track. If you find the problem, post and let us know.

 

[mstaylor]

Nice explanation on the things to check Mike. The only time I put travelers together anymore is when I am supplying trusses and curtains for theatre touring companies that are in arenas. That's why I came up with my bounce method, I can adjust the curtain while the show is loading in without having to have a lift in the way.

 

[FatherMurphy]

Detwisting the floor block can be as easy as loosening the clamp on the master carrier on the floor block side, and spin multiple twists into the end of the rope, opposite the direction the floor block spins. Work the twists back through the live end pulley, and they will neutralize the twist you are fighting. After some experimentation, you should be able to get the spinning down to a manageable amount. Some residual twist in the rest of the rope may work itself back over to the floor block, so you might have to repeat the process after a couple shows.