Buy a binary marble adding machine

I have sold all the machines that I built. I may at some point build another batch, but I have no immediate plans to do so. So the machine is not for sale at this time. You can try building your own using these plans though.

Even without me posting the machine for sale, I get the occasional email of people asking wether they can buy the machine. So I figured I'd experiment with selling some product online and built a batch of 6 of these machines.

The machine, without protrusions, is 28 cm wide. Overall, its 35 cm wide and 39 cm high. Its a tiny bit smaller than the first one I built, but I think it looks better. It uses the same type of marbles as the first machine.

The machine comes with 25 marbles, selected for size. They are just dollar store marbles, but not all dollar store marbles are the same size, even from the same bag.

It also comes with a wooden tray to catch the marbles (not shown)

I should warn you that on some occasions, especially adding large numbers, the machine can make mistakes. The large drops for the marbles on either side can result in the marbles bouncing around in ways that they shouldn't. You will see parts of the machine carved slightly here and there to minimize this. Hopefully, if I end up building another batch, I'll eventually figure out a set of dimensions that makes this unnecessary.

Cost is $250, taxes included. US or Canadian, seeing that they hover around par nowadays. I know that's steep, but I only built 6, and if I charged any less, there wouldn't be any chance of me building more once they run out :) Really, this is the worst conceivable deal imaginable on anything that computes!

Feel free to build your own machine - if you do, you can use my plans. In fact, once you have built your own, I'm sure you will have better understanding of why I charged that much.

Plans for a slightly refined version of the machine.

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