[Oa] Paper "Beam" for Swivel Roof Mechanism

[Jeff Gomes]

Selena-

Although most of my string experiments came close to positioning the roof as I wanted, none of them was really solid and reliable.  As each one failed to work as well as I had hoped, I kept disassembling and rearranging for the next idea.  I never thought about taking any photos of them. 

I will try to borrow back from its recipient the card I described that has the pivot and short string, so I can get photos of it.  Or I may just draw some diagrams and post them.

Although the recipient is happy with that card, I am dissatisfied with it since the roof does not close fully unless the card is flexed past 180 degrees to put some extra tension on the box.

Meanwhile, your description has given me an idea for another approach I had not thought of.  So I will proceed with more experiments when time allows and let you know how it goes.

Thank you very much for your help!

-Jeff

At 2341 -0400 05/03/2005, KSelena at aol.com wrote:
>Jeff & Andrew --
>I am intrigued by your descriptions of using string to make the roof swivel into place, I can't quite picture it. If either of you has photos of such mechanisms, I'd appreciate a look at it.
> 
>The swivel roof mechanism I'm familiar with has a sort of paper "beam" that runs from the front to back peaks which is attached to the peaks with tabs. Picture a rectangle for one roof side, fold down a 1/4" or 1/2" strip at the top to form the beam and have triangular tabs at the ends of the folded down part which are glued to the peaks at the front & back. You have to tweak the tabs' geometry to make it match the angle of the roof slope so the tabs don't stick out. And it helps the swivel if you make the roof width a fraction longer than the "beam" (which is exactly equal to the width of the side of the house) -- i.e., roof sticks out 1/16" or 1/8" on each side, forming a little bit of an overhanging eave. Repeat for the other roof side -- although I prefer to design the roof as one continuous piece with a sort of "M" fold in the middle -- the outside legs of the "M" being the 2 roof sides & the inside "V" part glued together ("|") to form the beam.
> 
>K. Selena Kim
>...