Comments on: Expanded table of points for drawing hypotrochoids and epitrochoids

By: xavier

xavier — Mon, 15 Jun 2020 09:21:01 +0000

Haether no the teeth are twice as big

By: Heather

Heather — Sat, 16 May 2020 23:34:39 +0000

In reply to Heather. I expanded the table to go down to 40.

By: Heather

Heather — Fri, 15 May 2020 02:23:07 +0000

In reply to xavier. Interesting! If the teeth are the same size as the regular spirograph, it must be small! Can you send me a picture? Actually, given the wide range of rings in Wild Gears, expanding the table would be a good idea.

By: xavier

xavier — Thu, 14 May 2020 04:21:57 +0000

I have an old 1990s hasbro spirograph with a circular ring that has only 48 teeth plus 7 wheels: 17,18,22,27,29,30,33. Too bad the list only starts at #50 ring.

By: Ron Peters

Ron Peters — Sat, 08 Sep 2018 18:07:13 +0000

Thank you for this table. It’s been a great help for sorting out the most usefull epitrochoids using the wheels. It is now easy to combine different outside wheels for a nice result with equal petals. Too bad the chart starts only at wheel 50, but there is very very much to try and figuring out!

By: Scott

Scott — Thu, 09 Feb 2017 01:28:10 +0000

In reply to Catherine.

You can also download an excel spreadsheet from here:
https://www.instructables.com/id/How-to-design-a-laser-cut-Spirograph-like-toy/
The instructable includes the formula to make your own sheet if you’re so inclined.

By: Heather

Heather — Sun, 22 Jan 2017 02:14:51 +0000

In reply to Charles Tomberlin. Yes, the fixed gear is along the top and the moving gear is down the side. The formula in cell B2 is =LCM(B$1,$A2)/$A2. I could delete the impossible combinations where the moving gear is larger than the ring. However, those numbers are useful for epitrochoids in cases where a large gear moves around the outside of a smaller fixed gear.

By: Charles Tomberlin

Charles Tomberlin — Sun, 22 Jan 2017 00:51:12 +0000

In reply to Heather. On your chart, you do not have the same numbers at top as on left side (B2 has 50 & A2 has 15). According to your instructions "Put the gear numbers you have along the top and the left side..", so I would think that you would list 15 both at top and bottom. We are trying to make our own chart, so could you please clarify? Is the top the inner circles (large fixed) and the left the smaller circles? Thanks in advance.

By: Catherine

Catherine — Sat, 31 Dec 2016 18:45:12 +0000

In reply to Heather. Thank you. I've recently started using the Full Page V2 Wild Gears and it's maddening not knowing how many points are going to happen. I'm not very good at maths.

By: Heather

Heather — Mon, 26 Dec 2016 04:51:34 +0000

In reply to Catherine.

Did you click the link to view the spreadsheet in Google Docs? It’s a big chart, so you’d need a pretty big monitor to see it all.

You can also make your own chart, depending on the gears you have in your set, using Excel or Google Docs. Put the gear numbers you have along the top and the left side, then use the formula below. Use it in the first box (cell B2) then copy to the rest of the cells. These are basic spreadsheet skills, so if you don’t know how to do it, get someone to show you.

=LCM(B$1,$A2)/$A2