My 6" f5 Newtonion at the 1997 RTMC where I picked up a Merit Award for Excellence in Metal Craftsmanship and Design. The head, with the exception of the thread on dec. shaft, and tapered bearings, was totally made of aluminum. The R.A., and dec. drives use gear reduction DC motors that are voltage regulated. It will run for around 100 hrs. on 6 penlights. Total weight of the head is a mere 14 lbs. which is not much considering it can support three times its own weight.
for more info if desired see the ATMJ issue #7
This was a fun project folding up a 3" f15 Refractor, I used a 1.83" diagnol at about half way of the focal length. Works great because the eyepiece ended up almost right across from the dec. axis so going from Zenith to Horizon you do not have to move around to much compared to a straight through Refractor. Also if you think I lost 10% more light, it's not so, because when looking at planets I remove the diagnol and look straight through with my head to one side.
Well is this one of the most bizarre looking scopes you have ever seen, yes its a 12.5" f8.3 folded Newtonion. The light cone is intersected with a 3" round flat about 24" before its focal plain, then bounced at about a 7 deg. angle out of the tube. The tube splits in the middle for easy transport the black light shield also is removed. Believe it or not there is no ladder required you can look right to the Zenith in total safety with your feet on the ground, imagine trying that before the fold (8.5 feet of focal length is just to much).
The 25" f5 dobsonion Lance Olkovik and I built is slightly different then most because to assemble it requires only 4 bolts, that's right the trussed assembly stays together all the time, we call it the oil derrick. The scope is hauled around by a full sized trailer that was designed specifically for it ,you just open up the ramp door, attach a couple of wheels to some poles, and rickshaw the rocker box and ground board any where you like. The oil derrick also rides on the poles to rendezvous with the rocker box.. In the photo you can see where the poles go through for transport. Setup takes about 5 min. which the Community Astronomy Program is very happy with.
