This is a 1979 to 1986 Vintage 12.5 inch Newtonian F 4.5 reflector built by Telescope World.
The main optical tube is made from Duralite – a composite material with excellent thermal and structural properties and painted with Dupont Imron paint. This combination gives impressive strength and durability to house the optics.
The spider is made from aluminum and features stainless steel vanes for strong support. The main mirror is # 7740 Pyrex and is corrected to 1/10 wave at 5000 Angstroms. It is supported by a 9 point flotation system.
The equatorial mount has 2 inch diameter stainless steel shafts fitted with Sealmaster bearings within a 4.5 inch diameter 6061 aluminum housing. The entire housing and other portions of the mounting are painted in Imron paint, which is exceptionally durable and is also used to paint aircraft. The shafts are fitted with 10 inch diameter setting circles and a 10 inch diameter polar drive with 315 teeth and a lead variation of 0.00006 inches R.M.S. The drive consists of motor with 1/2 RPM and a brass gear reduction system which tract at a rate of 1/1436.4 minuets. In final assembly the drive is mounted and lapped to provide ultimate smoothness. There is no backlash and the telescope is equipped with a joy stick controller to make astrophotography a joy.
The instrument also includes a tangent arm of 10 inch radius to control declination axis with a large surface area clutch and a 1/4 x 20 leadscrew.
The telescope mount sits in an 8 inch column with three massive legs attached for extra support.
This is a rare and interesting telescope.