Jeff Duntemann's Contrapositive Diary Rotating Header Image

March 12th, 2008:

Junkbox Telescope Gallery

Some years back I posted Jeff Duntemann's Homebrew Radio Gallery, and for reasons unclear it's become one of the most popular pages on my site. (Tube construction may not be quite dead…) So a while back I wrote up and (almost) finished a page about all the various telescopes I've built out of junk since 1966. Longtime Contra readers have seen some of the photos, but a few are new scans of prints I've had in a box for decades.

Jeff Duntemann's Junkbox Telescope Gallery sat unfinished on a thumb drive for some months, until I finally bore down and finished it a few days ago. It's not a how-to; there has never been and will probably never be a better junkbox telescope how-to than Sam Brown's classic All About Telescopes, which is in turn a compendium of shorter booklets that Brown published through Edmund Scientific in the early-mid 1960s. $14.95 is cheap for a book like this. If you ever have the least inclination to put together a scope from scratch, buy Brown's book first.

The page is mostly a photo collection, with some odd notes on how I did what I did. Note well that you don't have to grind and polish your own mirror as I did. Ready-made 8″ primary mirrors can be had for $300 or sometimes less, and the rest of the scope can be, well, junk. Also note that I think Dobsonian mounts are silly: With a 2″ 45° street elbow you can have something approaching an equatorial mount if you live in the US.

Building scopes like this is mostly a lost art, and there are definitely advantages to scraping up the cash for a Meade or a Celestron. (Tapping in “M31” on a keypad is less messy than lying on your back in a cowfield and sighting the nearly invisible object along the edge of the tube.) But it's a good kid project, because when you're done you—and any involved kids— will know exactly how it works, and that's worth something all by itself.