So what is a Spirograph. Well its a mathematical device that can
generate hypotrochoids and epitrochoids. In 1965 Denys Fisher sold
a toy version which I find hard to distinguish between a real and
a kiddies toy. In truth the Fisher version was pretty effective at
creating those wonderful geometric patterns.
I was searching for an A500 motherboard and I came across my blue
tray for the Spirograph wheels and I decided to go try and find all
the other bits. After a while I tracked down all the plastic wheels
but couldn't find the box or manual. So I flipped onto Ebay and
picked up a cheap box albeit a number of the wheels were missing.
So having put the wheels back on the tray and safely placed into
the box, I now have the complete set and can store that away. I
also have a spare tray and a further almost complete set of wheels.
Do remember when you look at these drawing tools there were no
computers to create mathematical patterns. The wheels did require
a steady hand as the pen was likely to slip and the cogs come
away from their larger wheel. It was amazing just how complex a
pattern you could create.
One other tool I use to play with as a kid was the 'Sketch-a-Graph'
which let you trace round images and reproduce them on paper. It
could also enlarge images. Not very accurate but gave you the bones
of an image to work with. One trick I used at school was to place
a piece of newspaper between an image and a blank bit of paper and
then simply use the blunt end of a pen to trace round an image
pressing through the paper. The newspaper acted as carbon paper.
Again remember that in the day there were no printers, photocopiers
and or computers. Everything had to be done by hand. And complex
calculations had to be done by using log tables, though later I
did buy a slide-rule.
You can get a Spirograph screen blanker for the Amiga but you need
Michael D. Bayne's GarshneBlanker installed. Just do a search for