Re: [ATM] flex rocker question

[Dave Smith <smithersscope@yahoo.com>]

Hi Rod,
I still haven't gotten my website back up, but I could
send you some pics if you're interested. (And let me
know what your connection speed is--I can adjust the
pics accordingly.) My setup is based almost entirely
on Mel's tri-dob design.

To answer your questions:
Yes, the alt. bearings extend below the mirror box.
This gets the mirror as close to the ground as
possible and thus the focuser/eyepiece as low as
possible.
Mirror storage: Well, once I fold up the mirror box,
it will NOT sit in the bearings in the flex rocker
(but I can store it flat if I place it down inside the
ground ring and flex rocker base.) It actually slips
right on down to the floor. Like Mel's, the mirror box
(when collapsed) will actually stand up on the bottom
edge and is pretty stable in that position. But I'm
paranoid, so I usually store it nested in the ground
ring/flex rocker. This puts the altitude fin directly
on the ground (carpet), but I haven't noticed any
adverse effects on the bearing. Ebony Star is tough
stuff.

A word of caution about the low position of the alt.
bearings in the tri-dob...the center of gravity is so
low that you'll likely have to add weight and/or Tom
Krajci's spring-based virtual counterbalance system to
counter a top heavy OTA and/or a thin mirror. I had to
add both (25 lb of lead....arrrggghhh!), but it is
working really well. My 16" f5.6, 1" thick plate
mirror scope weighs in at about 45 pounds (with the
lead butt) and I can easily set it up by myself.

I'd be glad to try to answer any questions you have
though my experience is limited to this one scope.
Fire away!

Dave 

--- Rod Brackenridge <rjbr@lycos.com> wrote:

> Hi,
> 
> I would like to build a flex rocker for a 12 inch F5
> newtonian.  I have been looking at some photos on
> the net to get some idea of what is involved.  My
> questions are:
> 
> It looks like the altitude bearings in most designs
> extend below the mirror box.  Is this essential?
> 
> Having them go below the rocker would seem to
> necessitate always storing the mirror box in the
> flex rocker and ring.  Is that how most of you do
> it?
> 
> Thanks,
> 
> Rod Brackenridge
> Mount Martha
> AUSTRALIA
> 
> -- 
> _______________________________________________
> NEW! Lycos Dating Search. The only place to search
> multiple dating sites at once.
> http://datingsearch.lycos.com
> 
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
_______________________________________________
ATM mailing list http://www.atmlist.net/