Earl is a great choice for a first model. The construction is straight forward, but the results are very special indeed.

  1. You will need one wire coat hanger, some glue or tape, and either twine or heavy yarn. Of course, you need scissors too, but that is pretty standard in this business. If you become particularly involved in model building, you may find yourself compulsively carrying scissors and X-Acto knives with you. Be careful. It can scare people.

  2. Bend the hanger (in the middle of the long side) to make an approximation of a square. Don't worry if it is a little deformed; this is not an exact technique.

  3. Now cut lengths of string long enough to stretch across the square and easily tie each end. Better to err on the long side, since you can always trim the ends. Tie the string so that it connects opposite sides, as shown. You can decide how many strings to use, but use at least one per inch. When you do the perpendicular strings, weave them in and out of the first set to add stability.

  4. Use some glue or tape to secure the strings. It won't be a disaster if you don't, but the knots will tend to slide around.

  5. Now gently bend the diagonally opposite corners toward each other, one set on top and one set on bottom. If you want, you can use string to hold the corners at a desired position. You should now see a saddle point, or hyperbolic paraboloid.

Here is a picture of the original Earl. This is the work of Prof. Gene "Darth" Klotz.

**Bonus to anyone who can figure where Earl's name came from [hint: think of homophones]**

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Joan Hoffmann
8 November 1995

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