HomeSpirographWhat is the radial distance between the holes in Spirograph wheels?


What is the radial distance between the holes in Spirograph wheels? — 18 Comments

  1. Heather,
    My new Super Spirograph just arrived in the mail today. The first thing I did was to repeat your interhole distance measurement for #80 gear going around #60. I drew curves through holes 1,11,21,and 31. The distance between 1 and 31 was 19.8 mm, giving 0.66 mm average. Very close to your 0.65!
    However, the distances for each 10-hole interval were not equal. Between 1 and 11 was 5.8 mm and between 11 and 21 and between 21 and 31 it was 7.0 mm. I’m planning more measurements in the future to get a clearer idea of how the holes line up, but I thought you might be interested in my preliminary results.
    I certainly enjoy your blog.

  2. Thanks for your contribution Harold. As you see from the diagram, I didn’t measure as many holes as you did. I’ll go at it again sometime too, using my old Spirograph parts. I should think that the higher-numbered holes are harder for the manufacturer to fit in, especially in the new sets which have larger holes, so may be less regularly spaced.

    Do let us know about any other results you get.

  3. I love the website. I found it while researching the different models that were made so I can make an informed decision when buying one on eBay. I decided I want an original 1967 Kenner model like I had as a kid because it has the most wheels and is the most precise according to you review. I’m not that interested in sets with extra tracks because I like the trochoids that the wheels make, themselves. I want to make a visual guide showing the patterns of every possible combination of wheels, rings, and holes. I will generate this using a script but I need the exact measurements of the wheel and ring diameters, tooth height and base width, and radial positions of the holes. Are you able to supply these? I will gladly email you a copy for the site when it’s done.

    • I’m glad you’ve found the site useful.

      I don’t have exact measurements, nor the means of producing them. They would require very precise measuring instruments which I don’t own. All I have is the little calipers in the picture. This particular article is as far as I’ve gone in measuring radial distances.

      I often hear from people who have found old Spirograph sets on ebay, etc. Hopefully you can find one and take measurements from it. Good luck! And feel free to share your work with us. The site attracts all kinds of people from artists to geeks, and some will be interested for sure.

      • OK, thanks. I just bought an original British ‘Spirograph By Denys Fisher’, the German inventor of the toy, from 1965, 2 years before the 1967 Kenner version in the U.S. I am still looking for a deal on a Kenner 1967 version to compare. I want to be really accurate and do the guide for the original Kenner set first if there are differences.

        BTW, you can get a really accurate, highly rated,
        6 in. Digital Caliper with SAE and Metric Fractional Readings, from Harbor Freight:

        Wait until they go on sale for $9.99, which happens often. You can subscribe to sale notifications. Quality test a few for smooth operation and repeatable accuracy. Make sure it remains at 0 when you turn it off and on again. Get only this one with the gray plastic readout. Item #68304. It is the latest improved model. Don’t get either of the old ones with the old black readout. Item #47257 or Item #61585.

        • Cool. I should think the Denys Fisher version would be as well made as any. According to Wikipedia, he was an English engineer.

          There are some online simulations listed at the bottom of the Wikipedia page. I haven’t blogged about them (yet). So many things to write about, and so little time (I have a web design business to run too). Check this one out:

    • Just when I was having fun with the rogue version when I should be working! It generates wonderful patterns.

      Check out this one from a reader – go to the “link to Spirograph Package” in the header:

      I’ve been wanting to play with it and write about it.

      (This site has been generating more options to write about than I have time for.)

      • Yah, I don’t know where that rogue version came from. It’s difficult to use and the patterns don’t always close. The original ones, developed by Andy Katz, are much better. I told him how he could improve them by using splines so they generate nice smooth scalable patterns now. The interface is all point and click.

        That spirograph program is Windows only. I use a Mac. But I prefer to write my own code anyway.

        The next thing you should get is a Magic Designer. They can be had cheap on eBay. They’re easier and faster to use than Spirograph and are built solid out of thick steel. Avoid the last plastic model they made. It is crap. I’d love to see you write an article about your experience with it. If you have time… 🙂

  4. I just lucked out on eBay and got an original Kenner 1967 Spirograph, red tray, in pristine condition with the manual and pin board intact. It should be interesting to compare this with the Denys Fisher version. I will report on any differences.

    • Hi Hany,
      All I have is an ordinary ruler so my precision is limited. The largest ring has 150 teeth on the outside and the diameter (not radius, d=2r) is about 97 mm. You can do the math from there for the other rings and wheels. Maybe you can buy a Spirograph set and check your math against the pieces, then try drawing some patterns by hand for a whole different experience!

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