General Tetraflexagon, Flexatube, or Bregdoid

To build the more complicated tetraflexagons, the individual squares shown in figures 27 (top side) and 28 (bottom side) can be cut out, labelled, colored, and joined together one by one. Figures 29 and 30 show larger squares which are already joined in groups of four and so would require less cutting and pasting. In either case, the figures should be regarded as mere templates, to be copied in quantities sufficient for any given construction project.

Either flexatubes or bregdoids can be fabricated from the strips shown in Figures 23 (top side) and 24 (bottom side). The figures contain three strips, which should be cut apart. Only one strip is required for a flexatube, so the material is sufficient to make three of them.

The simplest bregdoids are made from strips eight squares long; following which two of the longer strips must be at hand because they are going to be braided together before folding up in flexatube fashion. Therefore the material shown in the figures is only sufficient for three quarters of a bregdoid, and more copies would have to be made before proceeding.

Figures 27 and 28 contain the tops and bottoms of some generic squares with tabs for joining them together. They can be used in sufficient numbers to construct the more tortuous tetraflexagons, or even colored with original designs for making flexatubes or bregdoids.

**Figure 23:** Top side of a flexatube.
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**Figure 24:** Bottom side of a flexatube.
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**Figure 25:** Second copy of the top side of a flexatube, which provides enough additional material to complete the second strand of a bregdoid, and even to make one with slightly longer strands. Otherwise it provides for three more flexatubes.
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**Figure 26:** Second copy of the bottom side of a flexatube.
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**Figure 27:** Since even the straight tetraflexagon strips are jagged, the best way to make up a tetraflexagon is to paste individual square cells together. They can be colored and numbered beforehand if that information has already been worked out.
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**Figure 28:** Back side of a panel of square cells.
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**Figure 29:** Larger generic squares - top side.
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**Figure 30:** Back side of a panel of larger square cells.
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