Saturday, July 28, 2012

An harmonograph

Ever since my last visit to the MSMEE exhibition, two years ago, I have been wanting to build myself an harmonograph.  Just after that exhibition, two years ago, I was cleaning out my shed and found some old curtain rods which I decided would be perfect for the project and leaned them up beside the doorway instead of throwing them out.  I was keen to build a design that I could pack away neatly so I made the box long enough to store the longest spars.  The gimbals are turned from aluminium and pivots made from M3 allthread.  The paper platform is simply some masonite glued to a wooden block with a hole in the middle so that is sits tightly on the spar.

One of the surprises has been just how much variability there is in the setup and how much tuning is required to get good pictures.

The finished harmonograph

Some of my best works

Gimbal detail from underneath. One set of bottom pivots fitted to the box and the components for the second gimbal ready to go.

Neatly packed away

Hours of entertainment

Whilst researching construction details I came across Wayne Schmidt's multi-topic site.  The site covers everything from kaleidoscopes to electric rocket engines and deserves a nomination to the tinkerers hall of fame.