Hello Mark, & thanks for your kind comments. My 'profession'....I'm not officially qualified in any field, unless you want to take into account 35 years {off & on over the years} of basic engineering/design/welding etc. etc. My father was an engineer, & fundamentally with his input of knowledge and my labour, we made our first EQ mount when I was 13....So I picked up the knowledge on THIS basic EQ mount design from him, along with some new idea's that popped into me head as I was making it.
I was on a definite schedule when I constructed this last mount. In 2 weeks I had to design it, come up with the materials & build it. It's safe to assume that SOME of the materials used, were not picked by choice, but by necessity. {limited material choices where I live} In the last page of the plans I discuss what I would have liked to use instead of what I went with.
As far as driving it, I've already made a radial arm equal to a 22" {508mm} dia. gear.
Using a double curved bolt system requiring a 1 RPM motor to drive it. I've had it working, but the AC motor I was using was inducing high frequency vibration between the medium to high ranges of magnification.
Right now I'm mucking about with another drive idea using super magnets...totally isolating the drive/source physically from the telescope altogether. The results are......pending

Thanks for the links.
Kearn.....Ta mate.