Over the past few months I have been researching, designing and building a working RA with 360 tooth gear and worm and a tangent arm for Dec control on this old but goodie mount.
Earlier this year I bought this mount from Matt aka Kunama....thanks Matt
Nothing wrong with it at all but my DIY nature got into full swing and the process began.
RA first. Matt gave me a box of goodies that included an Astronomics 360 tooth bronze gear and worm. After much trawling around I settled on a slip clutch as the way I wanted to go. There was nothing left of the setting circles either so that was another thing I wanted to restore as much as I could. In another thread on JB Weld for Brass I found out that brass and aluminium do not go well together...in fact the two should not be mixed up together, thanks to everyone that responded to that thread. I had already cut brass circles and elements of the slip clutch from brass and decided that it's all brass or all aluminium. I went all aluminium for now as I had all the metal I needed and brass is expensive...but one day I will re build this in brass.
Time for some photos of the RA as it now is. I should point out that all this is easy to remove, should I ever sell this, and someone want to restore it to how it was when first built.
Photos left to right.
The mount before starting, the 360 tooth gear and worm, slip clutch and spring tension worm and gear and a side view before removing the brass parts.
There are a few more small parts to add mostly to the worm assembly to keep it in place when under load.
I want to add some simple form of stepper motor and control to this.Any ideas from anyone? I know zero about electronics. The scope is really well balanced so it doesn't move when pointed any where in the sky so I'm thinking that possibly a stepper motor for an EQ5 might be strong enough, with correct gearing?
As there is a slip clutch, moving the scope in RA manually while the drive is engaged is easy so I don't need fast slewing...though dropping GOTO on this might be nice, but that would mean a dec worm and ring gear instead of the tangent arm...so not a good idea.
So far so good...onto the tangent arm.
Matt