The Newtonian telescope dates back to the days of the Newton era, hence the name. Sir Isaac Newton, a British scientist, while playing around with a couple of mirrors and a scope, and eventually created the first reflector telescope in 1668. Amateur astronomers that are interested in building their own telescope normally favor the Newtonian telescope to reproduce because of its simplicity and ease of use.
Refractors and reflectors are the two prominent telescopes used by star gazers today, and these categorizations are derived from the type of light collecting tool the telescope contains. The refractor telescope utilizes several lenses to collect the light into the telescope, while the reflector instead uses mirrors. When building a telescope at home, the Newtonian telescope is often chosen because of the simplicity of the build. While people think that building a telescope that actually works like an expensive is complicated, it is a fairly straightforward project that can be completed without too much headache once all of the materials are gathered. The essential steps are below.
1) Purchase a mirror with the diameter of about 6” to 8” for the objective.
2) Create an octagonal tube constructed with slender plywood to ensure the telescope is lightweight. Glue eight boards, cut at 1/8” identically, around nine 1/8 octagonal formers each containing a 7¼” diameter cutout.
3) Pin together all the baffles and the ½” plywood back plate, then cut and sand them into shape. This will guarantee that they are all equal in size.
4) Cut eight 3 1/3” by 48” boards into 22 ½ degree bevels on the edges. Mark the bevels with the positions of the baffles. Using woodworking glue, glue the bevels to the marked positions. It is important to check that they are all square and vertical.
5) Start gluing the boards on carefully to avoid twisting. Glue one on one side, then glue a board to the other side, working around the tube alternating sides. Leave the final board off until the inside is painted and the project is ready to be finished. Give a second coating with PVA glue to strengthen to the joints, then let dry overnight.
6) Mark the spot where the mirror will reside inside the tube, and drill four holes to accommodate the ½” plywood cell plate.
7) Apply a coat of blackboard paint to the inside of the tube, and be sure to paint the last board that was left off. While the paint is still wet, throw some sawdust into the tube, coating the entire inside. Shake the excess dust out, and apply a second coat of paint to seal the sawdust in. Let this dry. Once dry, use a vacuum to clean up any stray sawdust.
8) Attach the final board to the telescope.
9) Coat the outside of the tube with sanding sealer, rub it down, and then finish off with a couple coats of glossy white paint.
The finished do-it-yourself at home Newtonian telescope will not only be fabulous looking, it will provide countless hours of viewing pleasure fueled by self accomplishment. It also allows the user a unique insight on the inner workings of a telescope and this knowledge will definitely help when choosing more powerful models in the future. In addition, a home built telescope is far less expensive than one purchased at the store and if built properly will deliver nearly identical or even clearer images of the solar system for the exploring astronomer.