An easy-to-make abacus
This is based on Mr. Barinque's excellent popsicle stick abacus I recommend looking at his page before trying to follow my directions. I made mine with larger beads and in the Japanese style instead of the Chinese style.
For excellent instructions on using the abacus, I highly recommend the website Abacus: Mystery of the Bead by Totton Heffelfinger and Gary Flom. They have a pdf instruction manual which can be downloaded for free and printed to make a very nice little book, as well as several pages of practice sheets.
In the early 1970s, before calculators were affordable, I bought a Japanese abacus called a "soroban" at an import store, and used it, along with my slide rule, to do my statistics homework. Recently I became interested in using the abacus just for fun. But my old soroban has tiny beads, and my old eyes and hands wanted something bigger.
Because my husband and I are both hoarders, I found all the supplies I needed around the house. The beads came from a Christmas tree garland. The dowels are 6" barbecue skewers. The strips of wood were in the woodshop. I'm very pleased with the result, a 12"x6" soroban with half-inch beads.
Cut two of the wooden strips to a length of one foot. They should be thick enough so that the beads won't touch the table when the dowels are laid on top of them. Mine were 3/8" thick and 3/4" wide. Cut two strips to a length of 6". These were also 3/4" wide, but happened to be a little thinner. These four pieces will form the bottom part of the frame. To give an idea of the size, here are the pieces for the bottom half of the frame, as well as one of the skewers with some beads on it:
Lay the two longer strips parallel to each other, and lay the shorter strips across the ends and glue. I used wood glue for this step, but switched to hot-melt glue for the later steps.
With wire cutters, nip off the sharp ends of 13 skewers. Put five beads on each one.
Glue the dowels, with the beads on them, onto the frame. Mine were about 3/4" apart. I neglected to take a photo at this stage. The next step is to cut two strips of wood to fit on top of the ends of the dowels. They should fit inside the end pieces. Mine were 10 1/4" long. This traps the ends of the dowels between two layers.
Turn the abacus over, and glue a narrower strip of wood along the back, to separate the "heaven" beads (worth 5 units) from the "earth" beads (worth 1 unit). I originally intented to glue it to the ends and to the dowels, but ended up gluing it only to the ends.
Turn the abacus back over.
I had originally intended to put another strip of wood on top of the narrower strip, to cover the dowels, as in Mr. Barinque's instructions. However, I decided I liked it as it was, with nothing to get in the way of my fingers. So that completes the abacus.
Postscript: I decided I really did have to make a popsicle stick abacus too, so here it is:
copyright 2005 by Karen Deal Robinson
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