Introduction: How to Make a Refracting Telescope

About: Hey! I'm Natanael Prado, a 21 years old boy who was born curious! I like technology, robotics, and of course, I love to make and invent things too! 😄

For a long time, I have been arousing interest in astronomy, I am fascinated sometimes looking at the skies and thinking of the stars and planets that are so far away from us. The observation of the sky is magnificent, I always observed the skies with the naked eye and never had an optical instrument like a telescope to appreciate the universe more intensely, it was then that the desire to create my telescope ignited in me, and I couldn't help but share with you how I made my telescope.

How do telescopes work?

One of the most important things that we have to know before we make our telescopes is to know how the telescopes work right?! So, a telescope is a tool that astronomers use to see far away objects, the two basic types of telescopes are the refractors and the reflectors.

Refractor telescopes

The Refractor Telescope is an instrument that uses lenses (objectives) and not a mirror and is attached to the front of the telescope to focus the light rays, in an eyepiece at the bottom of the telescope. It is the same system used in binoculars and almost all terrestrial telescopes.

Reflector telescopes

A telescope reflector is an instrument that uses a large mirror at the bottom of the telescope to focus light rays and a small mirror near the opening, which will reflect light into an eyepiece, located at the top of the telescope.

In this project, we will learn how to make a refractor telescope. So now that you know a little bit of the telescopes let's make our telescope!!!


Step 1: Materials

To make the telescope you will need:

  • 90 cm of a weldable PVC pipe 60 mm
  • 20 cm of a PVC pipe 50 mm
  • 10 cm of a PVC pipe 50 mm
  • 32 mm sliding sleeve for weldable Pipe
  • 25 mm sliding sleeve for weldable pipe
  • 1 60 mm lens with 1+ degree
  • 21 mm jeweler's loupe
  • 1 double-sided foam tape
  • 1 insulating tape
  • Matte black spray paint

To make the tripod of the telescope you will need:

  • 1/2" weldable PVC pipe
  • 3 PVC weldable caps
  • 1 small shelf bracket
  • 6 1/4 nuts
  • 5 1/4 flat washers
  • 2 1/4 x 1" screws
  • Durepoxi
  • 3 nylon cable ties
  • 1 PET bottle
  • Permanent marker pen

Step 2: Making the Optical Tube of the Telescope

The first thing that you have to prepare is the optical tube of the telescope, to make that you will need 90 cm of the 60 mm weldable pipe and 20 cm of the 50 mm weldable pipe, with these pipes in hand you will have to paint the inside of these two pipes with matte black spray paint.

After painting the pipes, you should take the 50 mm pipe and at one end, place a layer of double-sided tape. And then place the 50 mm pipe inside the 60 mm pipe. See the images below.

Step 3: Making the Eyepiece

To make the eyepiece of the telescope you will need to have the 32 mm sliding sleeve for weldable pipe, the 25mm sliding sleeve for weldable pipe and the 21 mm jeweler's loupe.

First place the 25 mm sliding sleeve inside the 32 mm sliding sleeve and use a hot glue gun to join these parts. Then glue the jeweler's loupe 21 mm in the 25 mm sliding sleeve and you will have your eyepiece finished. See the images below.

After doing this, place a layer of double-sided sponge tape around the 32mm end of the eyepiece and put place the eyepiece that you made inside the 50 mm pipe. See the images below.

Step 4: Placing the Objetive Lens

Now we have to put the 60 mm lens with a 1+ degree on the 90 cm weldable PVC pipe 60 mm. To do that put the lens in the side of the pipe that has 60 mm of diameter and then put "Durepoxi" that is an epoxy adhesive around the lens like the image below.

Note: Be sure to clean your lens before putting it in the 60mm pipe, a dirty lens will interfere with the quality of your telescope.

Step 5: Making the Tripod

The telescope is almost ready, but we have to make a tripod to stabilize the telescope and assist in the observation of the sky.

5.1 Making the telescope cradle

First of all, to make the telescope cradle you will need to take the 20 cm PVC pipe and make a longitudinal cut, then paint it with matte spray paint like the image below.

After that, scrape the middle part on the opposite side of the longitudinal cut, and use super bond instant glue and Durepoxi to glue a nut in it.

5.2 Making the tripod legs

To make the legs of the tripod we have to first mark ten centimeters from the lid of a PET Bottle and then cut that part. After that make three markings with equal distances on this piece of PET bottle that we cut, and cut it again making a kind of petals as shown in the images below.

Now, with the nylon clamps, attach each 1/2" weldable PVC pipe to each petal of the bottle. See the image below.

5.3 Making the telescope support

The tripod is almost ready, but we have to do the telescope support, so first make a hole in the center of the PET bottle cap, then place a 1/4 x 1" screw on a 1/4 flat washer from the inside out the bottle cap and secure with a 1/4 flat washer and a 1/4 nut on the outside of the cover. Once it is done, take the angle bracket and place it on the left end of the screw with a 1/4 flat washer and 2 1/4 nuts. At the other end of the bracket, place another 1/4 x 1" screw and secure it with 3 1/4 nuts and 2 1/4 flat washers. See the sequences of images below.



Now take the 20 cm PVC pipe and put it in this set that we have just made. See the image below.

Step 6: Enjoy Your Telescope and Apreciate the Sky

Now your telescope is ready and you can finally appreciate the sky. If you have any doubts about this project send me a question in the comment section below and I will do my best to answer your questions!! :)