The above Ad will no longer appear after you Sign Up for Free!

quick release

Discussion in 'Special Effects' started by silverbullet761, Feb 12, 2007.

  1. silverbullet761

    silverbullet761 Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Tuscaloosa, Alabama
    I need to drop a 4 meter high curtain (86 inches wide roughly) from about 3 meters in the air. It needs to be hoisted up from around a table via 30 lb fishing line (i'm using a total of 4 strands, 2 in the middle and 2 on the ends). I need to be able to drop the entire curtain on cue, all the way to the floor. The 4 hoisting wires (fishing line) are attached to a false top, which is about 6 inches long and spans the entire curtain. This allows for me to just hide whatever quick release system I can find behind the false top, and I don't have to worry about trying to release the curtain from the main hoisting wires. I need to know, what's the best technique or system to do a quick release? I want the curtain to fall evenly (as evenly as it can) and not have one side get released faster than the other. However, this is not a priority, as long as the entire curtain drops.

    What could I do for a quick release that could be triggered remotely (by pulling on a wire or something from off stage left)? I thought about using a quick release from a Bow & Arrow, but I'd prefer not to buy one.

    -stephen
     
  2. Footer

    Footer Senior Team Senior Team Premium Member

    Messages:
    9,413
    Likes Received:
    1,808
    Location:
    Saratoga Springs, NY
    Solenoids, electro magnets, that kind of thing would be the best option. Do you mind if you cut the lines?
     
  3. What Rigger?

    What Rigger? I'm so fly....I Neverland.

    Messages:
    1,091
    Likes Received:
    492
    Occupation:
    Polishing the brass on the Titanic.
    Location:
    Not at home, that's for sure.
    Okay, first things first in the name of safety:
    Fishing line is NOT acceptable for rigging ANYthing. EVER. If something happens and there is an injury, YOU can be held responsible in court.

    What you need to do is find a competent rigger to do this job for you.

    Fishing line is for just that-fishing. Not rigging.
     
  4. Footer

    Footer Senior Team Senior Team Premium Member

    Messages:
    9,413
    Likes Received:
    1,808
    Location:
    Saratoga Springs, NY
    Mono filament is used a lot for different things, its fairly common. Could you also define "curtain". From what i gathered, you are taking a curtain of 12', pulling it up to 9' at the top of the curtain, and then dropping the entire thing? or are you pulling it up to 21' from the top of the drape? Big difference there.
     
  5. avkid

    avkid Not a New User Fight Leukemia

    Messages:
    5,948
    Likes Received:
    225
    Occupation:
    Stagehand/ Production Company Owner
    Location:
    Howell, NJ
    Just because it's common doesn't means it is safe!
     
  6. Footer

    Footer Senior Team Senior Team Premium Member

    Messages:
    9,413
    Likes Received:
    1,808
    Location:
    Saratoga Springs, NY
    It completely matters what he is lifting with it. If its a piece of muslin that weighs 2 lbs, I wouldn't be worried about it. If its a 50lb velor drape with 100% fullness, then that might be a problem. Mono filament works very well in certain situations.
     
  7. wolf825

    wolf825 Senior Team Emeritus Premium Member

    Messages:
    1,155
    Likes Received:
    93
    Location:
    Eastcoast USA
    FWIW...monofilament is very common--but I agree, common it does not make it right. I would never use it as lift or rigging--especially when 1/8" & 3/16" aircraft cable is just as thin for very light loads...its just a not-safe and not secure product for overhead or rigging use.

    A few things folks forget about Mono that I might as well point out is that over time (whether in storage or in use) it deteriorates and becomes brittle easily, and as it ages it can lose its strength. It is easily effected by solvents, oils and chemicals which can break down its polymer bonds. It also is designed to stretch (a lot) under load and tension, and is just not designed or rated by anyone to be used as a overhead rigging or lift line in any manner. Once it stretches--it is not elastic--it does not stretch back..its next thing to do after stretching is snap...and there is no way to tell, except by a very fine experienced feel, if a piece has been stretched or not. As a former Redman tourney fisherman back in the 80's, I can tell you that most anglers change out or will cut away old mono that has been used or exposed to water/sun even only for a few hours, because it can and does deteriorate over time and exposure.

    Under UV light it deteriorates and becomes brittle very fast, under heat it melts and can stretch (stage lights get hot--and a light focused into a piece of mono will just cook it til it brittles and breaks very quickly). You HAVE to use special knots for Mono (Trilene knot for example) or it slips easily or is easily damaged--if you tried to use a square knot or regular clove hitch etc you could damage the line..and improper knots in mono can kink and weaken the mono making a easy breaking point. It is near impossible for a person to grab mono and securely grip it like a rope if they had to for lifting or tension--if you doubt that--try lifting a 20lbs sandbag with a strand of 25lb test wrapped around your bare hand and see if it does not slice into your hands like a wire cheese slicer into a bar of cheddar...

    Its designed specifically for a limited and specific use....using it (or anything) for rigging that is not designed or rated or safe for rigging, is opening the door for danger-danger-danger... If you wished to use Mono to settle or straighten out something--in a situation where it has no lift-support, like if you have a picture hung with proper cable, that you wish to keep from spinning or orienting off axis left to right, then I can see where it could be acceptable as a diagonal line...but anything more then that, or that would require it to be a support line...nope.. Simply put when it comes to rigging--you do it right, or you don't do it at all...

    As for the original question posted here--drop lines and boxes can be made using some creativity, or can be done using solenoids..depends all on the weight and how you wish to trigger the device and mount the device. If the original poster could provide some more info to that nature, then I'm sure the folks here could advise further on a possible solution(s)...

    JMO...
    -w
     
  8. silverbullet761

    silverbullet761 Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Tuscaloosa, Alabama
    Okay, let me clarify something. When I said "curtain", I meant I am lifting a very thin sheet (the thickness and weight of a bedsheet) NOT a full velvetine curtain. Also, our stage doesn't go up 21 feet. It goes up about 8 feet. I'm raising the curtain just above the sightline, so we can project a sillouette onto it from behind, with a small ellipsodial (sp?) and someone standing behind the curtain. That's all. I'm not trying to raise an entire curtain.

    Also, I'm very aware of the limits of fishing line, and how it CAN be unsafe. I've been fishing all my life, and I have used it in many a project. I am using 4 individual strands of 30 pound test line to lift less than a half pound of fabric. I am also aware of deterioration of the lines, however, our show is in two weeks, and the rig is completely temporary.

    I have only a few ideas for a quick release mechanism, and I've looked into solenoids and such, but I would just rather not rely on electic means to do this- there is to much that can go wrong and not enough time to properly test such a system. I'm looking for more mechanical, like pulling a small wire off stage to release it. Does anyone know where I can buy a quick release or know how much I would look at paying for one?

    and replys appreciated.
     
  9. vulcan

    vulcan Member

    Messages:
    15
    Likes Received:
    0
    Location:
    eastern us
    i have been working with a small production and we are useing electro magnets.....ive learned many things...they are very simple to make but you need to find a good balance between volts and amps.....for instance, a car battery would work great for my application but there are too many amps and the resistance in the circuit heats up everything very quickly. 6 volt flashlight batteries wired together in parallel provide lots of voltage but low amps and make it neccessary to use a lot of them. however, an electromagnet may be a good way to go if you have the time to experiment with your needs.
     
  10. jwl868

    jwl868 Active Member

    Messages:
    697
    Likes Received:
    47
    Location:
    Pittsburgh, PA
    Try this (from a stagecraft book)

    I am assuming that you have a pipe or something solid to attach the drape to. (But I’m reading fishing line, so this may be too much weight, in principle.) Attach two heavy duty eyelets about 1 inch apart to a length of wood. The openings face each other and the axis through them is parallel to the floor. A 2-inch (or longer) hitch pin passes though the eyelets, and rests on them (lots of “play” here). A cord attached the hitch pin, and the cord is supported off stage, turns down with a pulley, and terminates at a handle about 7 feet off the floor (arms reach). Note that the cord goes off to the side at the same elevation as the hitch pin, not at an angle, though you may be able to suffer a little deflection.

    Back at the hitch pin. The drape has now been fan folded or rolled up and is to be secured with another cord. I attached the two ends of the cord on the length of wood a few feet apart and secured them above the drape. There is enough cord for sufficient slack to attach a steel ring at the middle point of the cord (At the point of the “V”). Bring the cord around and under the drape and up to the hitch pins and eyelets; place the steel ring between the eyelets and then pass the hitch pin through the eyelets and steel ring. The weight of the drape will bear down on the hitch pin, and friction holds it all in place.

    Attach a fishing bob to the hitch pin cord, close to the hitch pin.

    Crisply pull the handle offstage, the hitch pin comes out of the eyelets, the steel ring drops free, releasing the drape. If you have this rigged in the right direction, the steel ring is hidden behind the drape. Meanwhile, after you release the handle, the weight of the hitch pin pulls the handle up, but the fishing bob stops at the eyelets, and the hitch pin stays up, out of sight.

    (Your backlighting may silhouette the ring and hitch pin, though..)

    Joe
     
  11. silverbullet761

    silverbullet761 Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Tuscaloosa, Alabama
    Well, the show came and went, and we ended up not using a curtain with a quick release. That was really just to give a really awesome finale sequence. However, there was also some stage illusion going on behind the scenes. The whole point of the drop curtain was to project the image of a sillouette onto the curtain, so it looked like someone was standing behind the curtain, then when we dropped the curtain, there would be no one there. We decided to make our lead disappear because we realized he would need to be off stage when the song in the finale ended. So, being having a hobby in special effects and stage illusion (stage magic) I opted for the classic way out-- a projector. This is how alot of pro stage illusions are done- with digital projectors. If you have ever seen where they have the magician or a "volunteer" locked in something or onto something with danger/death coming if they don't escape, and then they drop a curtain between the audience and the illusion and illuminate it from the back, that's how it's done. You are not seeing a real sillouette, that is a digital projection (trust me on this one- i know a person or two). This is the route we were going to take, and since our quick release curtain was up and working (very well I might add), I thought it'd be easy to project a moving image onto the curtain, so that way it looked all the more real and it was even wilder when we dropped the curtain and no one was back there. HOWEVER, I must give a few words of caution to anyone wishing to use digital projection onstage.
    1.) You need a very bright projector to be seen clearly, even if that is the only thing illuminated on the entire stage and the rest is dark, the light from a standard computer projector will not be that impressive.
    2.) Your image will be pixelized. TRUST ME. We used a very high-end DLP projector that my dad has for work- this is the kind that projects 1080i Nativly, and the pixels were still clearly visible. We then tried the projection of a still image, taken with a 8 megapizel digital camera, thinking that if it was the full resolution, it might look less digital. Still didn't work. You could clearly see the pixels all the way back to mid-house. One thing that sort-of worked was we blurred the image slightly, brought the projected image slightly out of focus so the pixels weren't clearly defined. This worked for the audience, but anyone that is kinda close to the screen can tell it's digital, and let's face it, if you are trying to pull off a "magic" trick on stage, it has to be flawless.

    At the end of the day, for my quick-release mechanism, I threaded two peices of fishing line through the curtain and false top, starting at each end, and having the lines meet in the center. I then fashioned a small device that was spring-loaded. You pushed two peices of metal together (driven apart by the spring) and then put a washer over the two pieces of metal to hold them together. The two peices of fishing line were pinched between the two peices of metal, and the washer attached to a "drop line". When we pulled the drop line, the washer was yanked off of the two peices of metal, allowing them to seperate and freeing the fishing line. The fishing line unthreaded itself due to the weight of the curtain, and the curtain dropped very evenly.

    Overall, I have to say that method worked quite well, I just wished really well, I just wished we could have used it...


    -stephen
    "never accept limits, they only limit you"
     
  12. SHARYNF

    SHARYNF Well-Known Member

    Messages:
    1,911
    Likes Received:
    157
    There are a couple of things that can help on the projection side of things.

    A lot depends on what you are originating from, is it a video camera, on the real subject or a canned sequence that you are using. Sometimes your problem is that you are starting with too high a res image, an rescaling. If you process the image you can put some blur in it. Sometimes the problem is lighting, and the high contrast on the edges, DV for instance tends to stair step on hard edges which is quite visable in a high contrast image.

    A lot of these are actually done with film, since high output projectors are easier with film, you then simply have two drop curtains, one is dropping as the other is rising, so that the projector is hidden from the audience.

    By far the absolutely stunning effect is quite expensive but really astounding.
    that we have ever done is the following

    Basically if you have two very large parabolic reflectors, with the front one with a hole in the middle, you can place something at the focal point between the front and rear mirror AND a full image in full "solid" will be projected out in front of the mirror with the hole in it.

    There are some inexpensive small setups that you can try, that allow you to put a small object in the mirror setup and it will be seen floating above the device. It was interestingly used for display of very high ticket jewelry items where the real item in locked down below but you can see it above.

    This is all and good, but the other point that very few people know is that if you place a scrim between the audience and the Mirrors. the image will pass thru the scrim BUT if you at the same time project onto the scrim an image from the side angle, you can make the scrim look solid like a wall or what ever.

    This is how you can really freak out an audience and make the sure they have seen a ghost since the created image looks quite real, floats, and of course is able to be passed thru etc. the scrim with the projected background covers up the mirrors.

    The only factor preventing this being used more frequently is that large parabolic mirrors of say 10 feet diameter are very very expensive, but you can duplicate the trick with small mirrors. You need to light the real image, add the scrim and project from a side angle.

    Sharyn
     
  13. leistico

    leistico Member

    Messages:
    56
    Likes Received:
    3
    Location:
    KS
    Just saw your thread, and for what it's worth, I had to help out with something similar for a dance company that came through our place. The entire number was done behind a black scrim hung just upstage of the grand drape. Blacklights, the whole nine yards. For future reference, what you're looking for is called (I don't know why) a kabuki drop.

    A wire is tied to the pipe, and the wire contains loops about 6 inches long spaced the distance of regular ties for a soft good (1' ?). That wire is also attached to a parallel wire, and for each corresponding loop there's a metal pin on that parallel wire. The scrim is held in place by feeding one wire loop through the eyelet on the scrim, then placing a pin through the wire loop to trap the scrim onto the loop. This is done in lieu of tying it to the pipe (the wire with the loops is the only thing tied to the pipe). The wire with the pins is extra long on (in our case) stage right, so that it extends to the floor when fully flown (gotta be careful flying it in and out, lest that wire gets snagged and you have to restart the whole hanging operation.)

    On cue, the dangling wire, connected to all the pins, is yanked, the pins pull out from the metal loops, and in under one second the scrim drops free into a nice neat pile directly under the pipe where it was hung. Very neat effect.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice