The Telescope
The Tube, refractor (not pictured)
The drive system. 
This mounting has been a long project for me. I donīt even exactly remember when I started it - its been over 10 years anyway.
The story of this mounting is still shorter than the main mirrorīs (305mm dia f=1405mm). I bought the Duran 50 blank in 72? - Iīm not even sure
about that either. Very soon after buying the blank, I started to make the first version of a mounting for it. (This one is the third version and hopefully the last).
When making the primary optics I realized that a good telescope for my purposes is much more than just a mirror. The mounting is much more of a challenge
than completing the mirror. So the mirror has been half finished for over twenty years and still is. The time to finish it, is when this mounting is ready
to be installed under the dome. So, why I did not finish the mirror when the second version was finished? Well, when that mounting was ready to be tested I naturally
installed my 6" scope on top of it. When quickly realizing the faults of that mounting (not good enough in my mind for photography) - I did not bother to finish the mirror.
Oh well, some people like to make mirrors, I quess I like more to make mountings...
The Tube, reflector
The top, bottom, and part of the middle is from a 400mm diameter aluminum printing press roll, wall thickness is 8mm. I have two top parts, one
is for the newtonian focus and the other for the cassegrainian secondary. (The main mirror is perforated.) The top part can naturally be turned a full 360 degrees
for a comfortable observing position. This type of an arrangement will give a major challenge in collimating the optics at installation time.
The truss tubing is made from 30mm aluminium tubing with a wall thickness of 3mm.
The Base
The frame is made from 15 to 20mm thick steel plates welded together. The RA shaft is 790 mm long, at the upper bearing the diameter
is 130mm and at the lower bearing the diameter is 75mm. The worm gear will be placed between the fork and the base. The shaft size at the gear is 150mm.
The weight of the base is close to 400kg.
Currently the base is structurally complete and the RA shaft installed.
The Fork
The tines are made from 5 to 15mm thick steel plates welded together. The middle part is a little heftier 10 to 20mm plates bolted together.
The Spider
The RA Worm Gear
Installing the RA shaft
DEC shaft
Base plate
This mounting will also carry a refractor. It will most propably be a 250mm dia with a focal lenght of 4.5 meters and it will naturally be a folded one.
Both RA and Dec shafts will be worm gear driven. The one for the Dec is from my current mount.
Itīs diameter is 380mm. Back in 87 I bought a larger worm gear for this mount, it is a 570-tooth 455mm diameter worm gear.
For the old gear I have to make a new hub as the shaft diameter changes from 75mm to 105mm, the old slip clutch cannot be reused.
The gears do not have slip clucthes, so both tracking and slewing must be done with stepper motors. Both gears have been made by E.R.Byers.
The telescope will be completely under computer control.
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