Ammunition for the rubber band gatling gun
Probably not long after the first rubber band was made in the early 19th century, someone hooked it over a finger and launched it at a coworker. Hand-launched elastic projectiles lack the accuracy and range of those fired from a rigid launcher, but rigid launchers have always been more difficult to reload, and thus suffered from low rates-of-fire. The application of Dr. Richard Gatling’s innovation to the field of rubber band munitions allows both higher rates of fire and greater range and accuracy than hand-launched elastics.
Preparing the Cylinder
1. Draw a circle, 2.5 inches in diameter, with the compass on a sheet of paper. Using the compass and straightedge, divide the circle’s circumference into eight equal sections. Then place the end of your 2.5 inch dowel over the circle on the paper and carefully mark off the dowel’s circumference into those same eight equal sections. With the straight edge, draw a line across the end of the dowel connecting each pair of opposite markings; they should all cross at the center of the dowel.
2. Cut a groove, 3/8 of an inch wide and 1/4 of an inch deep, down the length of the dowel at each of the marks. The ridges left between the grooves will be the barrels of your gatling gun, and the entire dowel is the cylinder.
3. Drill a hole, 3/8 of an inch in diameter, in the exact center of the dowel — you marked this in step 1 — and parallel to the dowel, about an inch deep, with the drill press. Change the bit to 1/8 of an inch diameter, and drill a second hole into the side of the dowel, about two inches from the end you drilled the first hole in, in the middle of one of the barrels and an inch deep or so.
4. Sand the entire dowel to round all the sharp edges left from your cuts. Be careful not to round the ends of a barrel so much that you cannot leave several elastic bands stretched over it securely without slipping off.
5. Cut a length of 3/8 inch dowel, approximately two to three inches long, and glue it into the hole you drilled in Step 3. This is the spindle.
6. Apply some glue to the small hole you drilled in the side of one barrel, and use a toothpick or stiff wire to force the end of the nylon cord as deep into the hole as possible.
The Crank Assembly
7. Drill a hole, approximately two inches in diameter, through the middle of a section of 2 x 4. Drill a second hole, perpendicular to the first and slightly larger than 3/8 inch in diameter, through the edge of the 2 x 4 so that the second hole passes through the sides of the first. With the same bit, drill a third hole, perpendicular to the other two, about an inch deep, to accept the spindle. While you have the drill press out, drill a 3/8 diameter hole through each end of the wooden slat.
8. Cut a four-inch length of 3/8 inch dowel, and try inserting it through the second hole in the 2 x 4 block. Don’t force it; it should be able to spin freely. If it doesn’t you will need to widen the hole until it does. Once you are satisfied with the size of the holes, take the dowel back out of the block for now.
9. Glue the four-inch dowel into one hole at one end of the slat. Just push the dowel into the hole so the end is flush with the other side; you don’t want it to protrude all the way out. Then glue a smaller — two inches or so — length of 3/8 inch dowel into the hold at the other end of the slat, but from the other side. This will form a crank, with the small dowel as the handle and the longer dowel as the shaft.
10. Sand the block, and the crank.
11. Insert the shaft of the crank back into the 2 x 4 block, and glue the other end of the string — the end that’s not attached to the cylinder assembly — to the shaft, as close as you can to the side with the crank handle without accidentally gluing the shaft to the block. Remember, you want the crank to be able to turn when you are done.
Assembling and Loading the Weapon
12. Wrap the string tightly once around the cylinder, and stretch an elastic over the string on each barrel. Keep wrapping the string and adding elastics until there is just enough slack left to fit the spindle into the hole on the block.
13. Mount the spindle in the receiver hole on the 2 x 4 block. If there is enough slack, you may be able to load another rubber band onto the cylinder. Once you have loaded as many rubber bands as you can fit, gently turn the crank to take up any remaining slack.
14. Turn the crank. This will pull in string from the cylinder, releasing a rubber band from the first barrel and rotating the cylinder. It will keep firing elastics as long as you crank, until it runs out of ammunition.