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Mark Hodson - Glenore Grove, Queensland, Australia

 

Mark made this telescope around one of my 12.5" f/6 conical mirrors be bought from me in August of 2004. The general shape was inspired from my own 10" f/6 featured on this site, though he elected not to make a rotating head. The telescope tube is made of plywood with the open cell made of aluminum and awaits its final coat of paint. 

At present, the telescope is sitting on an Atlas EQ mount but is destined for a larger home-built mount that is presently under design and consideration.

   

 

A side view.

 

Front view showing the head.

 

Struts as attached to central box.

 

Mirror cell made from aluminum. Conical mirror is held by a stud on the aluminum disk seen at the center of the mirror. 

 

Collimation adjustment mechanism.

 

The following is Mark's own commentary on building and using the telescope.

"Here are a few photos of the scope so far. I have built a temporary tube similar to yours on the web page but with changes for a 12.5" to fit onto an EQ6. Still have a few things to tidy up and an over coat of paint . The tube, all up with eyepiece and accessories comes to 16 kgs(35lbs) . Within the 18 to 25kgs (40-55lbs) limit of the mount (depends on who is selling the mount), but the length of the tube is where the limit is reached before the weight . It does drive it though, good enough for visual and web cam pictures.

"The tube is sitting back a bit as I have not fitted a finder or my Telrad but amazingly with them on and my heaviest eyepiece I managed to get the forward rear balance pretty well right on . Also got the focus distance and focuser height spot on and all my eyepieces and ToUcam web camera come to focus. That was a relief. I have to get my wife to make a cloth elastic shroud for the mirror end. 

"I have not used a rotating secondary cage on the truss tube but have placed two dovetail brackets 180 degrees apart on the center box and will just change between them - trying to save weight . The center box and the focuser end circles are 12 and 6 mm ply and I used 0.6mm aluminum sheet for the focuser tube. The trusses are 16mm 1.2mm wall. I cut holes wherever I could to save weight for temporary use on the EQ6 mount. 

"Have just come back in from a star test tonight, and words can't describe the view. Text book perfect, out of focus star images were perfect round concentric circles. Having done the test straight from garage to out side, there was virtually no shimmering of the images. I can't believe it was all so simple to do . Everything fell into place and just worked out."

As things progress with this telescope, I'll add new material.