A low cost solar scope

 A sun funnel is a solar projector designed by Rick Fienberg and Chuck Beater and was featured in the Sept/Oct 2011 issue  of                                                                     ASTRONOMY TECHNOLOGY TODAY.
                                                                 More information can be found here.

This refractor is made from a used photo copier lens, commonly called a "copy scope". It's approximately 60mm in diameter and projects the suns image onto the screen thru a 9mm eyepiece.

Low cost solar scope version 2

This scope is a 70mm f/10 refractor I found at a thrift store. The longer focal length of this scope allows the use of a longer focal length eyepiece (17.5mm) which makes focusing easier.

sun funnel 4

solar drive

The drive uses a simple worm wheel made from a stack of three wooden disks. The middle disk is 1/2 inch smaller in diameter then the other two. I filled the gap with quick setting epoxy and used a threaded rod coated with silicone to impress the "gear teeth" into the epoxy before it set. The wheel is driven by a 1/4-20 rod attached to a 1/3 RPM motor.