The 3 wheel Spirograph requires 9 inputs : the radii of the 3 wheels, their speeds and phases. Key in these in the respective cells to generate the spirographs. Setting one of the radii or one of the speeds to 0 creates a 2 wheel spirpograph. Note that the numbers can be positive or negative.

For example, see the screenshot below which shows a 3 wheel spirograph created by setting all the radii to 1, the speeds to -5, 7 and 1 and all the phases to 0.

The  spirograph shown below was made setting the radii to 17,2 and 2 and the speeds to 1,17 and 100. All phases were set to 0.

See this article by Victor Lua~na Cabal for a good description of spirographs and for more samples of  2 and 3 wheel spirographs.