How to make your own sunspotter
The general idea of the design is that you want to have a surface that is parallel to the plane of the equator, and the scope rotates in this plane to 'undo' the rotation of the earth. This way you only have one knob to deal with as you are trying to keep the sun exactly on target. Since the earth's axis is tilted 23° relative to the normal of the orbital plane, you need to be able to adjust the elevation of the scope relative to this equatorial plane by only + or - 23°. This is why this mount is simpler than a mount for a regular telescope, where you'd want to be able to adjust this angle all the way to +-180°.
With this thing you can make daily sunspot observations, and record them
on standard index cards. After a few days, you have a flip-book where you
can see the sunspots running around the sun's surface. It is easy enough
to do for 4th graders. Everyone gets to keep their observations. For full
details, see this page.
elevation gross adjustment sits on top of the disk, and the elevation
fine adjustment is a knob underneath the front of the scope. An image of
the sun is projected onto a standard 3.5×5 index card, held by the
Since the instructions have lots of pictures, I broke them up into a few separate pages. All measurements are in inches (with apologies to people who live in the real world).
Here goes: Makerspace has opened in Santa Fe, and there I have access to a ShopBot, which lets me cut all the plywood pieces semi-automatically. If you have access to such a machine, here are the CAD drawings.
Jan 2002, updated Jun 2017