[ATM] Wire Spider

[Gilbert Gagne <ggagne@clearwire.net>]

Hi All!
I've been experimenting with wire spiders for my new 12" telescope. I 
got the basic ideas from Mel Bartel's Tri-Dob Telescope article in the 
August 2004 Sky&Tel mag. I used 0.008" guitar wire and built a special 
jig for stringing up the spider. Its essential to assure that everything 
is centered and perpendicular and stays that way while tensioning the 
wires. Tensioning is done by adjusting nuts on cross drilled 6-32 brass 
machine screws. The wire ends are run through the ends of the screws, 
twisted back and soldered. Adjust by "twanging" each wire but they do 
not need much tension. Too much, in fact, and the wire easily breaks. 
You can view images at: 
http://www.atmlist.net/contrib/ggagne-at-clearwire-dot-net/12upper-ring.jpg
and 
http://www.atmlist.net/contrib/ggagne-at-clearwire-dot-net/12spider-jig.jpg
At the secondary holder the wires are secured by small screws. I used 
nylon washers under the screw heads to avoid cutting the wires.
The upper ring is not complete, still missing the focuser plate. The 
tapered shims and studs near the ends of the alum angles are for 
attaching the 6 truss tubes at the proper angles.
Gil Gagne
Port Orange,FL

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