I am posting this because it is simply amazing. I have developed a friendship with a local astronomer with over 50years of ATMing. He loves a challenge and unusual projects. We were at the Idaho Star Party this weekend in at the Bruneau Dunes State Park and I took off work a little early to meet him there and be some of the muscle he needed for his setup. He was originally going to bring 3 scopes (12" and 8" springfield and a 5"RFT ) but decided to leave the 8" home.
During much of the year he has this scope setup in his backyard but is able to stuff the parts into a DIY trailer for transport. When he opened the trailer it was like a Jenga block puzzle. Everything labelled and interlocked from floor to ceiling. We removed parts and pieces under his direction and over the next 2 hours the monster took shape.
The telescope is a Springfield mount scope with a 12" f/6 or 7 mirror. The OTA as you can see is massive. It is a 2 piece device locked in the middle. One end carries the optics which is basically a newtonian scope with a curved secondary spider. The after hitting the secondary the light is directed toward the EP which remains in a fixed position. In this version he has a stand that is about 36" tall that is the viewing platform. From the platform the scope can be directed to anywhere in the sky. Using his setting circles and no finder other than sighting along the spine of the OTA he is able to find objects to remarkable accuracy. (After hitting all 24 galaxies from the star party he pulled a list of VV objects about 13 mag that I had never heard of and was able to find the first one in a very difficult sparse starfield.) From the platform you can control the electric motors to turn on/off the tracking mechanism, or you can use ingeniously built controls that allow very fine slow motion controls.
From the viewing platform it takes very little to move the massive OTA. From the photo you can see counterweights on the polar axis shaft (about 60#) as well as about 30# on the other end of the OTA opposite the mirror. In this photo the mirror is at the bottom right of the OTA, there is a tupperware basin on the viewing platform where the person will stand when the setup is finalized. The motors and complex cabling is in the center of the pier. The large circle at the bottom right has cables attached for controlling the east/west motion. At the top of the pier is the bearing plate for the main rotation. I believe it is a 1" thick aluminum plate scavenged from a local scrap yard.
The other amazing thing about this project is that is took 6 years and was mostly put together with scraps, scavenged items, bits and pieces of motors, gears, cables and other items. To top it off he made it portable...in a sense with the trailer. Simply amazing.