Here you will find answers to a number of Frequently Asked Questions (FAQs) about the Telescope Making class itself. If you have questions that are not answered here, please either visit the ScopeX website, enquire at the class, or submit them by e-mail via the telescope making class discussion list (assaatm – see the Contact Us page, under Mailing Lists).

Q: Who can attend?
A: The class is open to all who are intrigued by telescope making. While membership of the Astronomical Society is not mandatory for participation, we would encourage you to join a Centre. This is not only because the class is run under the auspices of the Society, but because enjoyment of your telescope is enhanced by involving yourself in the complementary activities of the Society. See the About section of this web site for details of what else the Society does, how to join, etc.

We try to cater for both the beginner (who has not yet completed a telescope) and the advanced (those who have successfully completed at least one telescope).

If you do not wish to join the class, but would like to know what is involved in building a telescope, you are welcome to drop in and observe. We will try to answer any questions you might have, but remember that the class members have priority when it comes to having our attention.

Q: Where? 
A: The class meets in the Design Technology centre of Parktown Boys’ High School.

This is situated on the corner of Jan Smuts and Empire roads, Parktown, Johannesburg. Entrance is from Wellington Rd. (parallel to Empire). Go in the gate and follow the driveway to the right – it makes a right-angled bend to the left just as it hits some buildings. The technology centre is the building immediately to the left of the alleyway marked No Parking. Find a map here.

Don’t park in a no-parking zone: your wheels may be clamped, the car could be towed away. Besides, it would annoy us.

Q: When? 
A: The class runs most Saturday afternoons, starting at about 2:30 PM. You can begin now!

Our classes are pretty much ongoing, though we sometimes have a day out if there are other events on, and around major public holidays.

Q: How much will it cost? 
A: The class fees can vary from time to time according to the costs of materials, and of course according to the size of the telescope mirror you want. Please ask at the class for the current prices.

All other costs are for your own account, but typically it is possible to build a suitable instrument for about R2000. The money goes out slowly over time, and the actual cost is a function of your expertise, scrounging ability, ingenuity and of course the standard of finish you desire. To put this in perspective: you should end up with a scope that would be the equivalent in performance of one that would cost you at least 3x as much to buy commercially.

Q: Who do I talk to? 
A: When you arrive at the class, ask anyone and they will steer you to someone who can anwer your questions and get you started. The class is run on an informal basis and discussion is encouraged.  This is a “mutual benefit” situation, so you are expected to interact with and help each other as a matter of course.

Q: What is included? 

  • The materials for making the mirror (i.e. glass, abrasives, polishing agents). Glass disks are usually available in a number of sizes, ranging from 4″ to 8″.
  • A set of notes.
  • General instruction.
  • Use of the workshop facilities, which you are expected to treat with respect and help keep clean.

Since we help each other, the group also accumulates other materials that can be shared out among the members, either free or for nominal cost. If you have any special skills or materials to contribute to the group, or feel that you may be able to assist in any way in running the class, please volunteer them.

Q: What are we building? 
A: Typically a Newtonian reflecting telescope on a Dobsonian alt-azimuth mounting.

If you have any doubts as to which size you want, we recommend going for a 6-inch (150mm). This is the ideal beginners scope, manageable in size and easy to build. It will give you access to the craters on the moon, the belts and moons of Jupiter, Saturn’s rings, the polar caps of Mars, and more deep-sky objects than you can comprehensively observe in a lifetime.

As to further technical details, please don’t expect the course conveners to communicate them by e-mail: they too must work and somehow still have a life! Come to the class and all will be revealed.

Q: How long will it take? 
A: This is up to you: perseverance and commitment are the key determinants. Typically, you should be able to complete your telescope in about 6 months of spare time, and still have a life. Constant attendance at the class is not mandatory, but is HIGHLY recommended if you actually expect to complete your instrument. Building a telescope is a time-consuming and occasionally frustrating business, but the class is your support group. As long as you are prepared to persevere, and listen to instruction, you can do it! (If, on the other hand, you give up easily, you will probably soon drop out – so why bother?)

There are those … admittedly advanced, experienced telescope makers … who have completed entire telescopes, from first deciding to build it right up to observing with the fully functional instrument, in one week of spare time. Then, there are many who take 25 years (literally), and many more who NEVER complete their first scope. It’s really all up to you.

In the final analysis, no home-built telescope is ever really “finished”. You will always find something you would like to add, change, improve… in the end, you call it “done” and move on to enjoy it. In all probablility, if you do get your scope to this point, you will revisit these details later, or build another one incorporating the ideas that come to you over time. If the bug bites, you may find yourself building telescopes forever. You have been warned!

Q: What do I need to bring? 
A: For your first visit, it would be helpful to have a notebook and pen, but that’s all. We will explain all, at the time! Wear casual clothes that you don’t mind getting a little dirty.

Q: Anything else? 
A: All participation in any of the Centre’s activities is at your own risk. You will be expected to sign an indemnity form at the class, because we shall have access to potentially dangerous tools and materials (don’t worry: we haven’t lost anyone yet!)