[ATM] Equatorial platforms, 1 rpm motors, and First light

["Russell Jocoy" <russjocoy@hotmail.com>]

     Hello all,     I was very impressed with "Mitch's" description of first 
light with his mirror. We all remember that first urge to "rig" something up 
to see what this glass "dish" can project into an eyepiece.  We all remember 
how amazed we were to actually see something in "focus" let alone
an actual magnified image , even though the optic's were so badly aligned. 
This is when the mirror maker turns into the astronomer. Line up the cage 
and secondary, make sure the mirror support is adjustable, line up the 
optic's.... bingo or no go.. ( I forgot the star test, but many rookies 
do..)
   Coat the mirror and observe........uh, oh... 6 months later... need a 
bigger mirror... and so it goes.

    Now, to equatorial platforms... As all on the list have noticed both 
Astronomy magazine and Sky & Telescope magazine are having more and more 
ad's for EQ platform drives from many different manufacturers, (when I was 
young I considered a manufactuer some big huge company with a factory 
producing products)  These manufacturer's are the same people that produce 
many of the custom DOB's or equipment that goes along with the gear...Real 
people with a small group dedicated to perfection..  Let me inform some on 
the list that EQ platforms are made for Dobsonian type scope's so that they 
can track the sky as  EQ mounted tripod drives.   Dobsonian Telescopes are 
the basic ball joint of all types...No drive..
    These EQ platforms are not at all new,  They have been around most 
likely before the DOB.
Many on this list have made them, designed inovations to improve them, and 
now they are selling from $500.00 to $1500.00 made to order in consideration 
of the size of your "massive DOB"..
     I refuse to pay for a basic "rocker clock".....So.. I am going to make 
my own!!!
I have done the math, I know my lattitude, I have cut the "radius curves for 
the size base of my DOB, both "north" and "south"... I have a question.... 
where do I slice off the top of this curve?
I know the distance between these two curved bearings, but to my 
understanding the base to the ground is level to all directions, and the 
"rocker" or "DOB" base should be level to the ground base North and South  
since the east and west follows (or compensates) the earth's rotation.
       Do I set the two curved radius's  at my base width  and level them at 
any elevation I need???
I would like the least increase in elevation as possible. I do understand 
that these curved "bearings"
reflect the lattitude and are facing toward the south at that angle.. My 
question comes down to is what measure should  the deepest part of these 
curves be? both north and south. They can"t be the same  , can they?  I have 
loaded way to much information for one listing and will talk about 1 RPM 
motors later, of course they are related to the drive of this EQ 
platformonster...
                                     Russ Jocoy
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