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Rigging Question (Tieing off a line set)

Discussion in 'Scenery, Props, and Rigging' started by wemeck, Feb 7, 2004.

  1. wemeck

    wemeck Active Member

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    Back in my college days at SIUC they use to use tie lines to secure the line sets while loading. After a change in faculty the theater program started to use 4' pieces of 1x4 to twist around the ropes and then place the 1x4 between the arbor tracks to help prevent movement during weight changes. Well one day we ran out of weights at had to borrows some "pigs" from the campus events theater. While there I noticed they did not use 1x4 or tie lines but had a steel bar that had two or three 3" by 1/4" to 1/2" steel pegs that the ropes were fished through. I was wondering if anyone had seen or know of such a tool and what it is called? Also if you have any other suggestions on tieing off a line set.
     
  2. wolf825

    wolf825 Senior Team Emeritus Premium Member

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    This is usually called a "dog" on an arbor. Like "watch dog". Dogging an arbor basically means putting a catch or bind in the ropes to lock them off. This is usually done by sticking a piece of pipe--usually old bottom pipe works well, into the ropes and wrapping the ropes together to lock it off--and then propping the rope into the steel to hold it in place. Works very well and is very common--and there are various techniques when dogging a pipe and releasing it, especially when you have a heavy loaded arbor and you do not have wieght yet on a pipe..this is usually called "rolling the dog"...otherwise you risk a freefall of heavy weight that can get out of control. Rolling a dog alows you to maintain control while the pipe rolls. Additionally--the Dog in a rope simply binds the rope together so the rope will not run...if you were to simply twist the rope--the simple application of pressure to the twist will hold the rope in place.

    The other device you mentioned--with several smaller rungs that the rope is weaved thru--is a similar thing. It breaks the straight up and down tension on the rope thus binding it--and this device is used more in Nauticle and sailing applications then in Theater from my experience. But I have seen them in theater--and it works and is safe. Cannot remember the name of this instrument tho... If you have ever made a catspaw knot onto a loop or hook, this and dogging are similar in principle.

    Tieing off a rope is, in my experience, one of the least favorable and least safe ways to secure it, because you get rope onto rope that are usually of different sizes--and thus you can have "cutting" into the main arbor line by the hold line. Using rope on rope simply puts too much pressure into one spot on a rope and can weaken that area of the rope severely under heavy weight, where Dogging spreads out the grip and pressure among all the turns so it is even and not to one point. The dog pipe is simply a keystone to hold the dog in place... The tieing method also relies heavily in the person who wrapped the rope on and applied the tension..which IMO is open to slippage...where dogging--even if you did only two or three wraps, you are pretty darn secure and it cannot really slip until you either take out tension or remove the dog pipe.

    The only other way I have seen to tie off an arbor is to use a 1/2" - 1" webbing ring, and a clip.. Similar to tieing off, the web ring wraps a few times around the rope in a pipe-hitch type of way, and clicks onto the clip to hold it in place.

    Hope that helps...
    -wolf
     
  3. ship

    ship Senior Team Emeritus Premium Member

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    Stagecraft debated the various methods for safetying the rope/arbor a few months ago. Good debate went on between the “Line Lok”, twisting and the stopper knot/prusik knot. Stage Rigging handbook says 4 to 5 twists on the rope and never to rely upon it to hold an un-balanced load. Stagecraft also If I remember right had something said about the damage to the rope and equipment if the rope was too tight at the start. I always prefered the prusik knot method given a strong lock rail or other steel to tie off to. I would be using ½" spectrum dracon braided rope on 3/4" Stage Set X. Back to Stage Rigging Handbook, the synthetic rope allows for a tighter circle around the lineset for better grip. At least better grip for all but EZ-Trim linesets. I would not trust it for that rope. The book also mentions using this method alleviates stress on the tension block from the twisting. I have also seen Wolf’s websling used, both a repelling websling and the more rough commercial grade of 1" websling in a prusik. I still like rope for doing this better, I like the friction of rope more than slings, plus the easier bending in all directions.

    I prefer it also because there is little to no chance of a runaway or getting beamed in the head by the bar - I used to use 3/4" sch. 40, much less if you use it to control decent, you don’t have to get it out of the way before the twisted rope gets hit by the carriage. Also the knot will allow you to slip it down in acting like a safety for out of balance loads. That’s what I used to use. This method also allows you to check the balance without untying it.


    The Line Lok or “Uncle Buddy” believe it or not is not sold by Sapsis Rigging. Three is a decent drawing of it in the book of how to construct one as well as a sample of a commercial version of it, and I think also some new designs and sources for it presented on Stagecraft. What was it 9 months ago. Uncle Buddy might be a search phrase of use. I like the idea of them because they allow you to lower the line with friction, but if you need to slow it down you just raise the lever some or hook it’s lower half. Good idea up until the arbor gets too low for it’s use. That say 4' drop between arbor and tensioner unless you get a ladder to unload weights before hand can do a lot of damage.

    A hoist or winch might be a final solution for locking off the lineset.


    In general, I differ from Wolf in opinion of the advantages of tying off verses twisting. A knot around a rope will be more distributed than a rope lock’s pressure or cutting into it. If your rope locks don’t cut into the hand line than a prusik won’t either. On the other hand, twisting the rope can be bad for it in addition to the tensioner and other rigging parts. The tensioner is still taking the main load plus the tension load while with rope tied off to a pre-arranged to be safe place and not always the lock rail, you get a lot less load on the tensioner pully and a lot less problems with slack in the line after you max out the tensioner due to the twisting. In other words, unless you like a lot of play in your lineset, you will have to keep re-adjusting it with the twisting.

    On dogging the line off, I tend to agree that it’s easier to twist a pipe around it than dog it off using rope to do the same thing as the pipe given this is what you mean. Not sure I have ever seen this method used. I have also never seen tie line used anywhere around a fly system.
     
  4. soundman

    soundman Well-Known Member

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    wow thats instreasting amazing what happens outside of your little theater, we just use a 4 foot 1*1 that we called a 'snub' to prevent sliping while transffering wieght much like the one mentioned. That worked fine Untilll we stripped an electric of 'just a couple lights and some cable' and the snub like shot out and the runawy arbor was been held up by 3 people and osme one had to resnub it. It turned out that the person that put in the snub only did one twist and the 1*4 was barely been held in now we take wieght off as it is taken off the arbor like it should be.
     
  5. wolf825

    wolf825 Senior Team Emeritus Premium Member

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    Ahh..ya...well the dog only works when its wrapped at least 3 or 4 times. Less than that and it will roll and pop out. Just like a catspaw knot. FWIW, the dog shouldn't really be wood--wood is dense and can splinter and cut up your rope. smooth bottom pipe sections that you cut the threads off of, and smooth over, works..the best dog pipe I have seen tho was solid rod about 1" thick and rounded on the end--resembled a huge marlin spike. The correct and proper method for arbors and unweighting is what you said tho--unload and strip at the same time, or unload the arbor to pipe, and then strip.

    wolf
     
  6. EntRigger

    EntRigger Member

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    RE: Metal Line set lock

    In the second edition of the Stage Rigging Handbook of Glerum, he gives instructions on how to use it and make it in his book starting on page 150. He calls it a Line Lok, he also mentiones it can be made in a shop or bought in a store.

    Hope this is the same thing,
    Jason
     
  7. The_Guest

    The_Guest Senior Team Emeritus Premium Member

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    At all the venues I've worked at I have never seen any extra hardware or anything done to secure the lines while loading other than just using the standard rope locks. Why is this? I'd like to introduce these methods to my facilities, because with the ways I've seen people operate this stuff lately is disgusting. I'm always up for more safety in show biz.
     
  8. ship

    ship Senior Team Emeritus Premium Member

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    Rope can slip in a rope lock thus my 80# figure for it’s capacity I read off stagecraft last week. This is very dependant upon the age and wear on the ropes, much less that ropes of no matter the type will tend to flatten out some if not used constantly in those areas under the head or foot block. Such flattened out ropes will tend to prevent the otherwise adjustable rope lock for the time of the season (we all do adjust our rope locks do we not?) from gripping flattened out rope the same as rope normally at rest without bearing on a pulleye. I also remember that if using a hemp line, it might start out at 3/4" but in a few years it’s more like 5/8". Same with a few other styles of cable be it with how much squeeze they develop over time within the rope no matter the size it seems to be or in general wear and stretching out. I forget the figure to how frequently it’s necessary to change a hand line but it’s something like every five years if I remember right. In any case the rope lock is insufficient to trust to hold and out of balance load thus the commercial rope locks or twisting of lumber, pipe or what ever around them in preventing movement. Otherwise the prusick knot is also useful especially as a safety when moving an out of balance load given a good solid place to tie off to. Best option is what we had way back when in high school and that was a wire rope winch with pulley that could be individually mounted to any foot block with the hook attached to the carriage so as to more safely move a load out of balance. This after one spectacular crashed arbor. At times I have also used a block and fall.
     
  9. soundman

    soundman Well-Known Member

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    Every five years? I can't say that any of the high school theaters I have been in follow that, granted they are really only used for 4 or 5 shows worth compaired to a real house which may do upwards of 100 but still five years that seems a little frequent, not that I doubt you, just seems a little outlandish.
     
  10. ship

    ship Senior Team Emeritus Premium Member

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    Does sound outlandish and it could be more recommendation than anything else such as a fire link on the fire curtain or vent needing replacement every three years.
    Been a few years since I pulled rope for a living but this figure might be about right. More that the rigging system needs a professional inspection every year no matter how much it's used and at that time the hand lines would be inspected for possible necessity for replacement.

    Stage Rigging Handbook along with some for free off the JR Clancy website or Sapsis Rigging's tech notes would have such and more info.
     
  11. techieman33

    techieman33 Well-Known Member

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    the "unlcle buddy" can also be called a buddy bar, and i prefer them over using a piece of pipe, they give you a lot more contol, when you let it off, you can still use it to slowly let the arbor down. They are really easy to make, i think it cost me around $3 of supplies in metals shop, and took me an hour to make. If i remember right, there rated to hold something like 250lbs. and you can put a twist in the rope with the buddy and hold more weight.
     
  12. ricc0luke

    ricc0luke Active Member

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    I recently was part of the rigging for a show at Krannert Center for Performaning Arts @ U of I. Most of what we hung was light weight stuff, so we just used the 'uncle buddy' method. When we had to move the legs and the hang the heavier set peices, we used a 1" or 1 1/2" thick peice of wood which was the equivelt to a brook stick- a smooth finish with no splinters. What no one has said is that when you use that method, you are supposed to pull the floor tension block all the way up to give you the slack to twist the rope. If not, you are streching the rope unnessacary.

    Just out of curiosity, do you all spike your ropes with tape or with ribbon insterted into the rope?
     
  13. propmonkey

    propmonkey Well-Known Member

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    with our current system(its condemed) we used to just use tape, the ropes were to stiff to twist apart. with our new one coming in the summer we will use ribbons.

    can someone post some pictures or links to the before mentioned equipment, im just not getting a clear image in my mind.
     
  14. techieman33

    techieman33 Well-Known Member

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    I like flourescent gaf for spike, and then i hang a blacklight, and it's impossible to miss the spikes, and it doesn't really harm the system, as long as you take it off after the show.
     
  15. Tweedle

    Tweedle Member

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    I find that Bazooka Gum and Elmer's Wood Glue works to secure a lineset while loading weight. 2:1 ratio (gum to glue) . :rolleyes:

    Actually, at FSU, we use Uncle Buddies, and axe handles to break-off handlines.

    I always get confused at how to use the Uncle Buddy. So I usually just stab it with the axe handle.
     
  16. Dcdjdrew

    Dcdjdrew Member

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    there acutily is a product made just for this purpose and for the life of me cannot rember the name
     
  17. msaunier

    msaunier Member

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    Hey everyone,

    My buddy and I are doing a Senior project for our engineering class and we have to define a problem and invent or innovate something to make it better.

    The problem we have identified is that un-balanced line sets have to be tied down and be "saftied" to the rail in case the load becomes to much for the lock to handle.

    We are thinking of designing a tool the you can easily put the ropes in to secure the load. We are having trouble getting enough justification for the problem.

    Would you guys use a tool like this? How would you justify the need for this tool? Also, do you know of something that is already out there so that we do not steal any ideas or come into patent problems.

    Help a brother out!

    Take care guys.
     
  18. erosing

    erosing The Royal Renaissance Man

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    Assuming you are talking about unbalanced lines during weighting and not that your lines are always out of weight enough to need to be safetied, see below.

    This is just one example (from in-house productions), there are many slightly different ones, basically to replace a snub line, safety hitch, or prusik hitch.

    Almost everywhere I've been that has had a counterweight system has used knots or made their own "tool(s)." It's a good project, cheap, and there are a number of exacting plans available.

    ImageUploadedByTapatalk1348579483.897464.jpg
     
    Last edited: Sep 25, 2012
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  19. Sony

    Sony Active Member

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    476433_10150647277137688_180171617_o.jpg

    It's called an Uncle Buddy or more officially a "Line-Lok" and it's use is controversial, some people swear by it, some people swear AT it.
     
    bobcatarts and (deleted member) like this.
  20. DuckJordan

    DuckJordan Well-Known Member

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    Well Secoa said its okay for our space so I'll swear by it, I personally have seen how it will help when your line set can get close to 300-400 lbs over weight. Your average rope lock shouldn't hold more than 50lbs on its own. honestly the safest thing is to take a piece of steel make two twists between the two lines and tie off with a rope shackled to the rail.
     

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