Build a Home Made Telescope
These plans are for a homemade telescope that will be cheap to build.
At the time, this telescope only cost $10 to build.
We're missing part one, where they begin to polish the mirror, but have the rest of the plans! And really, who wants to polish a mirror for days?
From the plans: "The polishing stroke, as we have indicated
before, is similar to the grinding
stroke. In other words, two inches forward
and two inches back. Keep up
the good work for at least a half-hour.
Now stop for a look-see.
Remove the mirror from the pitch lap,
wash off the rouge, stand it on end to
dry, then sit down, and cool off."
"So, how can you be sure that you are
polishing a paraboloid? Easy enough.
You can test your mirror by means of
3 very simple rig invented by a French
physicist called Leon Foucalt. The method of testing a mirror to see
whether or not it is a paraboloid is
known as the Foucalt. knife-edge or
shadow test. You will need a pin-point
source of light which can consist of a five- or ten-watt candelabra base lamp
mounted on a block df wood and then inserted
in a cardboard tube as shown in
[read the full plans in the PDF]
How to Build a $10 Telescope Plans