While commercial telescopes use aluminum, amateur builders can adapt everyday materials. Heavy PVC pipes can be used, though they are prone to minor sagging in hot weather. Excellent alternatives include rolled marine plywood or carbon-fibre tubes. Internal Baffling
To help you get started on your telescope-making journey, it would be useful to know a bit more about your current plans. If you are interested, I can provide more details on , recommend trusted suppliers for optical glass blanks , or explain the testing methods used to check lens quality. making a refractor telescope norman remer pdf 12 new