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Vertical Mouth Cable Mechanism

I am attempting to create a simple cable-operated mechanism for a rod puppet with a vertically oriented mouth. I am very bad at anything engineering-related, so I've been struggling. I attempted to have a loop of fishing line fed through vinyl tubing secured with a hook that would "close" when pulled downward, but after trying latex tubing and cutting various-sized wedges to create a weaker hinge, I had no success. I tried another approach with two pieces of tubing glued to the lips of a latex test skin, and it was only slightly more successful but provided very little movement. I found this mechanism online and emailed the creator but have yet to receive a response: https://www.instagram.com/p/BozhEi3nclw/?igsh=YnhnOW45M3R3dm1x but this seems to be the best approach I would need.

So far, the puppet's armature is made with brass tubing with eyelets for joints and secured with epoxy. The "head" is a piece of brass tubing that will be operated by a rod secured around my thumb, like this design by Hobey Ford: https://www.instagram.com/reel/Cuf6zm7Nish/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==

This is probably very easy but like I said, I am very illiterate when it comes to anything with moving parts, my brain is far more inclined to aesthetics than functionality so I need it to be explained to me like I'm five. I have a video with a test skin demonstrating my desired outcome but I don't think I can attach video files in the OP. 

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    I cant share the video of the casted test skin but here is a WIP pic of the sculpture before I finished and molded it to give an idea of what I'm trying to accomplish: 


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    Update: I've been trying to make a similar mechanism out of steel wire like this eyelid mech, but I can't get them to align, and it seems the mouth is too small for something practical with this design. 

    ;
    credit: https://www.eldergeeksman.com/blog/2015/2/3/ithorian-eye-mechanics
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    Is the skin latex or foam latex? Regular latex can be stiff and may require a lot of force to move depending on its thickness.  It's hard to tell from the photo, but it also looks like any movement of the mouth may pull on the face if the mouth does not have enough material to close on its own.

    A cable-operated mechanism does seem to be a good option here.  Part 2 of this course has a section that focuses on making a mouth mech that may work for your application:
    https://www.stanwinstonschool.com/tutorials/how-to-make-a-foam-puppet-part-2

    /Chris
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    @Chris Ellerby The test cast I did is regular latex but the final skin will be a silicone with an equivalent softness to Platsil Gel 10. I'll check out that course and see, thank you.
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    I would need it to return to an open position. Could I make a little hinge out of ultrasuede or a similar matierial, or would it not be strong enough? 
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    If you need it to return on its own you may need to add a spring, elastic, etc. to the mechanism.

    A fabric or ultrasuede hinge should be fine.  It just depends on the range of movement and your tolerances.   Fabric hinges can move around more, so it depends on how rigid you need your hinge to be.

    /Chris
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    Darrell GreenDarrell Green ✭✭✭
    I wish I knew what the material is but my brain says "sticky hands". Remember those really stretchy toys that had the hand on the end of the really stretchy cord? They were always in candy machines and sold at novelty shops. If the material were available for molding.... and if I knew what it really was.
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    From what I can find, the "sticky hand" toys were made out of hydrogenated polyterpene resin.  Some modern versions are made out of a low-durometer silicone with an additive to make them more tacky.

    /Chris
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    I used a piece of craft leather as the hinge and made two crisscrossing "tendons" like the eye mech I posted earlier, and they seem to function. I am finishing the entire puppet armature, but hopefully, the silicone will cooperate; I'll update. 
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    Awesome, glad to hear you are making progress!  Looking forward to seeing your results!

    /Chris
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