Would the Moonlite ball-and-socket truss connectors work? http://www.focuser.com/cgi-bin/dman.cgi?page=category&plugin=dstore.cgi&cate... They are certainly much cheaper than the McMaster joints. I use these to connect my truss tubes to my secondary cage and find they work great for this intended application. -Tho On 8/10/07, Kurt Fisher < fisherka@csolutions.net> wrote:
I am interested in fabricating a Hargreaves strut similar to that seen at the attached webpage -
http://www.apstas.com/astrotas/mathers/southerncrossobservatory3.html
and discussed in the Sept. 2001 issue of Sky & Telescope at pp. 114-115.
The business guts of the strut are two plastic universal ball and socket u-joints. Using the S&T article, I have located the ball and socket joints at http://www.mcmaster.com/ at $33 for one joint. McMaster 60625K96 Plastic Ball and Socket U-Joints $32.85 a piece
I was wondered if anyone knew of a suitable lightweight substitute part that might be available locally at a lower price? Essentially, any ball and socket joint that can be fastened to a 1" or 3/4" aluminum pipe would work. I don't think the ball and socket needs to move in 3-D; a hinged connector with 2-D movement like McMaster 98010A290 would also work.
I have checked local awning retailers without success.
- Kurt
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