Re: ATM balance point in a dob

["cosmo23" <cosmo23@email.msn.com>]

Make sure you are getting full contact with your teflon aganst your formica.
You can attach some fine sand paper to your formica and by moving your
telescope up and down in altitude you will mold your teflon to the shape of
the arc your formica is attached to. After you get good contact gently sand
the teflon perpendicular the motion of the telescope. You can even go with a
heavyer sandpaper. Be careful you don't expose the nails or scews that you
are using to attach the teflon. You can also ruff up the formica a little,
again sanding perpendicular to the altitude motion. Has worked for me. David
----- Original Message -----
From: CharlesMitchard@aol.com
To: atm@shore.net
Sent: Friday, June 15, 2001 9:59 PM
Subject: ATM balance point in a dob


Greetings all,
I've just completed renovating a 6" f8 dob.
I built a bearing box to clamp to the ota with what I thought was the
bearing
axis aligned with the ota centre axis.
It balances with the heaviest eyepiece in but only between 20' from
horizontal to within 15' of vertical, ie outside of these elavations it
either continues to vertical or drops to horizontal.
I've overcome this with an adjustable  friction type of device that does not
impede the smooth movement so there is not a problem but as this is the
first
telescope I've built I wondered what I've done wrong.
The bearings are teflon and ebony star.
tia
Charles