Please turn on javascript in your browser to play chess.
Posers and Puzzles

Posers and Puzzles

  1. 28 Apr '08 11:07
    Does anyone have any good ideas for constructing a freestanding structure that will span 500mm out of only newspaper and cellotape.

    The bridge must hold as much weight as possible 200mm above the ground and and structure cannot exceed 500g.
  2. Standard member wolfgang59
    Infidel
    28 Apr '08 11:32
    Originally posted by Kiwi kid
    Does anyone have any good ideas for constructing a freestanding structure that will span 500mm out of only newspaper and cellotape.

    The bridge must hold as much weight as possible 200mm above the ground and and structure cannot exceed 500g.
    Is this homework?

    My pupils made Warren Girders from rolled newspaper (incredibly strong) then assembled the warren girders in pairs to make bridges. (Again joining with tubular paper).

    The exercise demonstrtaed the strength of using tubes and triangles in construction.

    A tip for joining two tubes is to use a smaller tightly rolled piece of paper as a joiner so that it sits inside both tubes - you can then bend this to whatever angle you want.

    Good luck
  3. 29 Apr '08 01:01
    Not realy homework, more of a fun design challenge. I want to design the best structure. Thanks for the tip, I have decided the best way would be some form of truss using rolled paper as the members. That sounds like a good way of joining them.
  4. 29 Apr '08 08:36
    One super long piece of cellotape might be an option.

    Phil.
  5. Standard member uzless
    The So Fist
    30 Apr '08 04:18 / 2 edits
    Originally posted by Kiwi kid
    Does anyone have any good ideas for constructing a freestanding structure that will span 500mm out of only newspaper and cellotape.

    The bridge must hold as much weight as possible 200mm above the ground and and structure cannot exceed 500g.
    Take long strips of tape, hold one end, and then twist the tape into a long twisted row of tape. You can now use the twisted tape as cables and make a cable stay bridge...or even a suspension bridge.

    Plus it'll look way cool.
  6. Standard member wolfgang59
    Infidel
    30 Apr '08 11:37
    Originally posted by uzless
    Take long strips of tape, hold one end, and then twist the tape into a long twisted row of tape. You can now use the twisted tape as cables and make a cable stay bridge...or even a suspension bridge.

    Plus it'll look way cool.
    Nice idea! A suspension bridge will be very fiddly - v. difficult to get all the lengths right. A cable stay bridfge (like the QE2 at Dartford) will be easier, maybe with just 2 or 3 stays? You will still need girders to make your actual platform rigid so get rolling that paper!
  7. 01 May '08 03:50
    The suspension/cable stay bridge is an an interesting idea. I have two questsions.

    1. how can the cables (twisted cellotape) be strongly connected to the bridge?

    2. How am i going to make the towers strong enough so they don't collapse when the bridge is loaded? If they are made of rolled paper they will be strong in tension but not under compression or bending.
  8. Standard member wolfgang59
    Infidel
    01 May '08 15:48
    Originally posted by Kiwi kid
    The suspension/cable stay bridge is an an interesting idea. I have two questsions.

    1. how can the cables (twisted cellotape) be strongly connected to the bridge?

    2. How am i going to make the towers strong enough so they don't collapse when the bridge is loaded? If they are made of rolled paper they will be strong in tension but not under compression or bending.
    Are you doing any work on this?

    1. Run a cable stay through one of your cylindrical girders and knot at end.

    2. Tricky. Perhaps an arch bridge is better to take heavy weights? I dont think compression will be your problem but bending will be, (since a heavy book can easily be supported on paper columns because the weight acts stratight through the column.)

    Good Luck