To start , I would like to thank everyone for their time. And yes, my description was not very accurate, but my drawing skills are even worse. What I am describing is a condom - like device that will last longer, can be put over a fire, weights more but not overly so and one that can be used to make a distiller (actually two of those must be used). To that end, I propose:
The device will be made from some kind of metal that will probably withstand a fire but be able to collapse as well. Like the material from which icecreams are packed as not to melt, from Haagen daaz for example.
The open end will have a metal ring as a stablizer, over which the 'water condom' will fold. Also, over this ring a plastic cup will fit.
At the closed end, the ' water condom' will end to a metal plate, so that it will withsatnd the fire. The plate will be circular and smaller than the ring, so that it will rest inside the ring when the 'water condom' will fold.
The plastic cup will fit over the metal ring on the open end and will completely cover it to prevent accidental water loss. It will also completely envelop the 'water condom' when closed. Finally, it will have a small covering opening that will enable straw perhaps to pass in order to use the ' water condom' as a distiller. So overall:
Outer ring: 2,5 cm diameter
Bottom plate : 1,5 cm diameter
Length open : 20 cm ??
Lenth closed : 1,5 cm ??
The above specs are approximations. So my questions are:
Is there a material that will withstand the fire and the folding? I plan to experiment with plain aluminum foil soon.
Is it possible to fuse the metal plate at the bottom without the fire destroying it?
What will the final length be when closed, do toy think?