By Claire Gillespie – Updated Aug 30, 2022
Interested in astronomy but not ready to shell out for a high‑end telescope? You can craft a robust 9× Galilean telescope using inexpensive, readily available materials. With this home‑built instrument, you’ll be able to spot lunar surface details and view Saturn’s rings as a distinct disk.
Order the lenses from a specialty optics supplier and grab the cardboard tubes at a local office supply store.
Remove the inner tube from the telescoping housing. Using the coping saw, cut two spacer pieces roughly 2.5–4 cm long. These spacers will secure the objective lens inside the tube.
At the end of the outer tube, drill a centered hole in the removable cap using a drill or electrician’s punch. Apply gentle pressure for a clean cut.
Drill a small hole on the outer surface of the inner tube. Place the flat side of the eyepiece lens against the removable cap, then insert the lens and cap into the outer tube. Apply a dab of glue to the hole, spread it evenly, and press the lens firmly in place. Allow the adhesive to set before setting the assembly aside.
Cut the closed end of the outer tube to expose the desired depth. Drill a matching hole around this area, insert the first spacer, and apply glue. Rotate the spacer to distribute the adhesive, then press until the glue sets.
When the first spacer is dry, position the objective lens so that the second spacer sits against it. Apply glue to the corresponding hole, spread, and press until it cures.
Slide the inner tube into the outer tube, fine‑tune focus by sliding the tube as needed, then fix both ends permanently with glue or tape. Once set, your 9× telescope is ready for sky‑watching.
Enjoy a clear view of lunar craters, Saturn’s rings, and other celestial objects—all built from everyday materials.
