# Make You Own Soroban Abacus

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The abacus has been around for centuries as a counting tool. It has mainly been used in the East, Russia and Europe. It is versatile as you can add, subtract, multiply and divide numbers on base 10 (normal counting), 16 (for counting ounces and pounds), 20 (as the Mayans did). For more information, follow the link:
https://en.m.wikipedia.org/wiki/Abacus

The great advantage of the abacus is that the user acquires a great ability to perform calculations with great speed. As a college professor, I am always looking into new ways to interest my students and make them learn much more than just the class topic. This semester I am showing them how to use an abacus and I decided to built my own. You can easily find them online but there is a special feeling of completing your own abacus.

ABACUS SELECTION

As I am a new user of the abacus and can still only add and subtract, I decided to built the simpler version. That is the Japanese Abacus named Soroban with 4 beads in the lower part and 1 bead in the top part. Nevertheless, the technique can easily be modified for the Chinese abacus, Suaban, with 5 beads in the lower section and 2 beads in the top… or even the “Mayan version” with 4 beads in the lower part and 3 beads on the top as they calculate on a basis of 20.

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## Step 1: Materials and Tools Needed

In a hobby shop I bought
• Beads (to make a 13 row abacus I needed 65 beads)
• Shish kabob sticks that would fit into te beads (one stick per row so I used 13)
• A piece of balsa wood 36”x3”x ¼”
• Crazy glue
• Sand paper

Tools
• Xacto knife
• Aluminum ruler
• Pencil to mark the wood
• Small hand saw
• Drill with bit the size of the shish kabob sticks

## Step 2: Determining the Size of Your Abacus

Measure my beads to determine the size of my abacus. Leave a little room between the beads so they move freely. In my case, the 13 rows of beads required 10" space as I was leaving 1/2" additional space at each end

## Step 3: Drilling Holes for the Sticks

Using a metal ruler and the Xacto knife I prepare a balsa plank 36”x ¾”x ¼” and cut 3 pieces 10” long. Leaving ½” on each end I marked the location of the 13 holes. Set the planks on the board and drilled the 13 holes on the 3 pieces at once

## Step 4: Inserting the Beads for the Lower Section of the Abacus

Insert the shish kabob sticks and slide 4 beads into each one and insert the second plank that will be the divider between the top and bottom section of the abacus. I advise to use shorter sticks as the long ones tend to bend and even break when sliding the second piece of balsa.

## Step 5: Finishing the Top Section

Slide the last bead in each stick and put the third piece of balsa on top. Slide all pieces to the size you desire. I used a gap equivalent to the height of 2 beads for both sections (top and bottom). Depending on your frame and bead sizes, it may be better to use a space equivalent to 1 bead.

## Step 6: Gluing the Sticks to the Balsa

Be sure to have all 3 pieces of balsa perfectly parallel and aligned. Use a drop of glue to set each stick within the pieces of balsa being careful to have the beads away while doing it. Then cut the extra Length of the sticks as close as you can. It does not matter I there is some left as you will sand it later.

## Step 7: Finishing It Up

The last steps to finish your abacus are:
• Using ¾” width balsa turned out to be too thick for the center piece. Sliding the top bead is difficult so I suggest using a divider the same size of the beads.
• You can dye it and decorate it as you wish to make it truly personal.

I AM SURE YOU WILL FIND THE ABACUS EXTREMELY INTERESTING!
It is fascinating to use and you can find how to use it following this link:
http://m.wikihow.com/Use-an-Abacus

## Step 8: Final Remarks

• Using ¾” width balsa turned out to be too thick for the center piece. Sliding the top bead is difficult so I suggest using a divider the same size of the beads.
• You can dye it and decorate it as you wish to make it truly personal. Just be careful to protect the beads so they slide free.

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## 13 Discussions

Thanks for a really great project. I discovered the abacus several months ago and ordered one from China. There are excellent addition and subtraction lessons here: https://www.youtube.com/channel/UCNxgTiv9tRfrN9g4j...

If the link doesn't work search for the HEV project on YouTube. These are children's classes explained slowly and clearly, just what my addled old brain needs. What's amazing about the abacus is that you slide the beads and the answer appears. There is no thinking about addition and subtraction, it is a totally different way to think about math.

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could You please post a picture of you abacus? It would be nice to see an authentic one!

Many thanks for your comment! I too believe that an Abacus is a fantastic counting device and every student should learn how to add and subtract on it. It helps us with basic math (numbers under 10) and as you say, the answer just "appears" on the abacus.
I will certainly follow up on the abacus classes as I am interested in learning Mora about it.
Take care!

You might check out

https://play.google.com/store/apps/details?id=com.igkandroid.densoro

1 reply

One of the funniest devices I have ever seen are these:

http://www.ee.ryerson.ca/~elf/abacus/images/abacus%20calculator.png and

http://laughingsquid.com/wp-content/uploads/Calculator_1.jpg - apparently for people who will use a calculator, but want to check it with their abacus... =)

1 reply

many thanks! Really, it beats the purpose but seem as nice way to introduce a calculator to a abacus user! :)

Easier than how I made mine. I was broke in college, so I used chopsticks I cut and glued together (there was a sushi place on campus). I'm out of practice, but I figured out how to multiply and divide on it (might've required my 17 row one).

1 reply

Your abacuses look fantastic! CONGRATULATIONS!
I will get into multiplying and dividing and I will follow your advise... a 17 rows abacus!

I knew there were different types of abacusses. Did not know my favorite was Japanese. I too can only add and subtract but if I make my own, maybe I will be motivated to learn more.

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It is a fascinating counting device. So easy to built it is no surprise it was used over such a large area crossing the borders within cultures over time. Built your own and I am sure you will be motivated to learn more about the abacus and its use. Please post a picture of your own abacus!