Thursday, August 24, 2017

coiling snake pop-up card

This is a card for a nephew. I've sent cards to his mother, my favorite sister, but this is the first to him, my favorite nephew. I play favorites. Why not?

I've done coiling snakes before based on an arm glued into crimps pushed into a paper step. When the card is shut the step also folds shut and the crimps in the two corners fold shut along with it.

When the card is halfway opened a single step forms to the side, with its two corners crimped.

When the card is fully opened the steps are stretched to flat band and the crimps in the corners are also fully flattened. all you see is a band.

The tiny triangular shapes of the crimps are used to glue an arm to attach to flat doughnut shapes. The discs are centered first then the arm is trimmed to fit and glued. With a snake pattern drawn on the disc it really does look like a snake coiling because the discs move in opposite directions. But you only get two coils and a third disc glued to the surface of the step. The crimp-coils rotate under the step. The step is drawn to look like a branch.

I kept trying to think of ways to have the snake coil around the branch. I kept thinking about a series of steps like a staircase that shows as such when the card is half opened, and that's still a possible solution.

This idea takes a different track. This relies on an arm attached to the side of the card where there is no snake action. It's placed on a hinge 1/2 inch away from the central fold, when the card is fully opened. When the card is closed the arm at the hinge travels upward in an arc to 1/2 inch height and then folds shut over the snake coils 1/2 inch from the central fold but now in the opposite direction. That means the arm and hinge travel one full inch. That's significant movement in pop-up terms.

This arm has slots cut into it for levers to transfer energy from horizontal to rotational. The levers are arms that hold coils with snake patterns drawn on them lined up in a row. When the first arm moves horizontally then all five lever arms move vertically in an arc and all five snake coils turn a little less than one inch.

This card relies on paper rivets for the lever arms holding the snake coils.

Fourteen photographs follow.







The rivets are based on double bowtie shapes. One bowtie in a square is glued to the background and the other bowtie in the same square is folded in thirds, both sides of it, so that the two triangular flaps can be shoved through a corresponding hole cut into an arm and cut slightly larger than the bowtie circle. This leaves a bent up mess of a paper bowtie with risk of being torn or slipping back through the hole. So another square button the same size as the original is glued to the folded messed up bowtie. It works surprisingly well. So long as no glue gets on the arm.







The snake disc is centered around the button and glued to an arm in only one spot. The rest of the disc flops around. This allows a branch to be run through them concealing all the rivets.






This prototype was abandoned. This is actually the second prototype. I went a little further than this but did not photograph the rest of the effort. The upward angle caused problems. The main arms were reinforced twice and guides were provided to keep them aligned. When branches were added to disguise the mechanism and to partially hide the two snakes then there were too many corrections and too many layers stacked on the arms and too much interference between parts. The hinges are unstable. Everything began interfering with everything else. It's overloaded and unsteady. 

So I reverted to one snake and straightforward horizontal arm. This third card went relatively quickly given the troubles were all worked out. The snake in this third iteration rotates unimpeded and very well. 

But I'm still disappointed. That's who I am. I just cannot be pleased. The whole thing is too flat. Nothing pops up. Nothing stays up while everything else around it drops away. There is no actual pop-uppery going on, just five discs rotating slightly. So where's the fun in that?  However, it really does look like a snake coiling around a branch, so there's that at least. It's sneaky while also anticlimactic. 

I wrote a birthday message in the blank area and for the cover drew an Egyptian (what else?) holding a snake. The cover says, "I couldn't find any good flowers so have a snake instead." 



I don't know about this. I like it and I don't. 

I think it will be better in combination with something else on the page that actually does something. I kept thinking of making the tree more dimensional. Or populating the page with people. There is plenty of area in the upward direction that's available. It's just too flat. And I don't like that.

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