Typical 'Dobsonian type telescopes'

The following pictures show three telescopes which will break down into 3 main sections along with a number of 'struts' which can be held together in a home-made bag for ease of packing. This type of unit can be assembled in just a few minutes - but is very compact for packing into a car or small S.U.V. for transport to a dark site for better viewing.

The first (and larger) is the Author's 12-1/2 inch, which can be broken-down into three sections, a base, a 'mirror-box' and thirdly the upper cage section. Weight of the assembled unit is 50lbs (approx 23 Kg) The mirror is 19lbs.(approx 8.6 Kg) The struts are aluminum 5/8" square tubing some 38" long.

The second pair of pictures illustrate the construction of this type of "Dobsonian" telescope. This one is for a 9 inch mirror. and is now completed. This weighs only about 20 lbs(9 Kg) as it has a light-weight mirror. (Port-hole glass) The tube section has the struts permantly attached, and fits with two 'suitcase clasps' to the mirror box.

 12-1/2 inch  telescope picture
construction of 9 inch 'scope assembled  9 inch 'scope

The completed 9" 'scope
finished 'scope
This construction is more complex than the normal round tube and 'rocker-box' placed in the swivel-base of the basic "Dobsonian" but it is much easier to transport...The tube length of my 12-1/2" is about 46" and the mirror-box and base are about 14" by 14" square, so they fit nicely into a small car...The 9" unit is smaller and could fit easily into a compact-car. The rings at the top are cut with a router, the struts are either hardwood dowels, 1/2 to 3/4 inch diam.depending on the size of 'scope, or they can be made from strips of the better types of plywood, or even strips of hardwood cut from a 1/2 or 3/4 inch board. The mirror-box and base are made with regular (or, good both sides) plywood or, if you want it to be nicer - with apple, maple, birch, or some other high quality plywood.

Below is the Fraser Valley Club's recently re-built 20 inch telescope

 The Fraser Valley  Club's newly re-built 20 inch  telescope

Constructed with the "strut type" method. Again this is broken down into three main sections. In addition there are two "wheelbarrow" handles which attach to the sides of the base section for ease of moving the unit around. The following picture shows the 20 inch alongside the 12-1/2 inch, this gives an idea of the size of the 20 inch when assembled:

The  20 inch and 12-1/2 inch  telescopes

If you plan to build this style of telescope - whether 14 or 15 inch or larger size - I recommend that you buy the following book which gives very detailed instructions for the construction of larger size telescopes, "The Dobsonian Telescope" by Kreige and Berry, available from Willman-Bell Inc. p.o.box 35025, Richmond,Virginia 23235. U.S.A. and may be ordered from your local bookseller.

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