How to Make a Telescope (Part 3 Making the telescope)
How to Make a Telescope: In this part of the tutorial I show you how to assemble the telescope
In this part of the telescope making tutorial I show you the nuts and bolts of how to make and assemble the telescope. I also have a video that shows you this and how to find the focal length of a lens. The picture below shows the parts needed to make this telescope.
Parts and tools
- Two cardboard tubes around 12″ each; one should slide into the other
- Two lenses of differing focal length
- Two small pieces of corrugated cardboard
- Scissors, pencil, razor knife, paint and glue
In part two you figured out the focal lengths of your lenses and you cut your tubes to appropriate lengths now all you really have to do is cleanly attach the lenses to the tubes. This can be a bit tricky and I went through a whole bunch of trials before I found a way that was easy and worked well. Here is what you do:
Put a lens down on the square of corrugated cardboard and draw a line around it. Do this whole process for both lenses. (make two of these)
Using an X-acto or razor knife cut the circle out. You can use scissors but it is rather difficult because you will tend to bend and distort the cardboard. Try to cut the circle so the hole is just a tiny bit smaller than the lens. Maybe about 1/32 of an inch .
Pop your lens right into the cardboard. Because of the thickness of the cardboard you should be able to squeeze the lens right in there and it will hold tight. If you have trouble or it doesn’t hold tight then just use a little bit of glue and let it dry.
Now, with a pair of scissors trim the cardboard ring so it is the same diameter as the tube. Remember that you have two tubes and each one is a different size because one slides into the other. Trim the ring with the long focus lens so it is the same size as your thicker outer tube. And trim the ring with the short focus lens so it is the same size as your thinner inner tube.
Now glue each ring onto its respective tube.
Slide the thinner tube into the thicker tube and your telescope is complete. Have fun!