The kaleidoscope was invented by an Englishman, Sir David
Brewster, in 1817 when he proved that the reflections of an object
seen in many mirrors create patterns. Any number more than one may be
used.
I first played with a 3-mirror kaleidoscope made in the 1930's by my
Aunt from soldered kerosine tins and candle smoked glass.
One of my first turning jobs, before anyone told me it was difficult,
was to make a complicated model mounted on gimbals. My later ones are
much more simple. I will describe a simple one and there is a diagram
at the end of this article of a jig to cut tapered staves. This is an
improvement on a straight cylinder.
Cut six pieces of wood (Diag. 1a) approximately 12 mm thick and
300mm long with the edges at 30 degrees to the vertical. Any
measurements given will work but can be altered but, be accurate as
the fit determines the final strength of the hexagonal tube when the
strips are glued . Strips of different colour veneer between each
stave give an interesting effect.
To glue up, (Diag. 1b) lay several strips of P.V.C. insulating tape
sticky side up on the bench and line up the staves, coat the edges
with glue and then roll the staves to form the tube and clamp with
more tape , hose clips, or in the case of a tapered tube, push
appropriate sized rings down and jam them in place. Leave the clamps
on.
Turn a pair of dummy centres (Diag. 1c) to fit into each end and
mount between centres on the lathe.
Turn a spigot (Diag. 1d) 12mm long on each end to accept the two end
caps
Dummy end caps may now be turned, fitted onto the spigots and mounted
between centres so that the clamps can be removed and the outside
diameter of the body turned and finished.
You now have a round body with a hexagonal bore and a spigot on each
end.
The end caps can be made now but don't glue until the mirrors are
fitted.
The perspex for the eye piece, (Diag. 2a) can be cut on a slow band
saw. Don't let the cut get hot or the perspex will melt and stick.
The eye piece should be a firm fit on the spigot and will hold the
perspex in place when it is glued on to the body.
The other end ) is made up as in (Diag. 2b) and should also be a firm
fi
Hint. When cutting class, dip the cutter head into turpentine
before making a firm positive mark on the glass. Don't let the glass
know you are afraid of it!
The three mirrors (Diag. 3) should be about 3mm shorter than the
body. Tape them together into a triangle with P.V.C. tape which will
stretch and hold the pieces firmly together. Wrap a few turns of
plastic draught excluder tape around the mirrors so that they are
firm and cushioned fit in the body.
Fit and glue the end cap and the eye piece in place after placing a few (12 at most) pieces of coloured glass between the perspex discs that make up the end cap. Check that they slide about easily.
Now, have some fun.
Hold the bottom end up to the light and look through the eye piece
while rotating the whole unit. Watch the patterns change.
I would love to see your results and the variations in design .
Good Turning
