Re: ATM First Steps

["Frank Ward" <thewards@pop.mindspring.com>]

Hello again Jake,

Top of the evenin to ya,

Most of your parts will probably come from the
major cities in the UK.

Local glass of the 1.5- 2" thickness you need
is rarely carried by local glass companies.

Remember when you buy, they usually sell
two to a kit but you need only one.  In the last
several years we've gotten away from grinding
glass on glass and now grind a "tool" on the
glass blank. The books I recommended  will
show you how to make a tool with a plywood
back and dental cement with tile on top.
Then You'll have your pitch (tree sap-balsam)
tool to polish with (and figure of course)
But that'll be later


The thicker the glass the longer it takes to
stabalize to new temperature, that's what
we want during the evening when temps
are falling.  A thicker mirror  is also heavier
and that is good for  balancing your scope at
a convenient point to reach the eyepiece.
Some makers use very thin mirrors to achieve
the same thing......but usually not the first scope.
If you stick to tried and true methods the first
time you'll know what you want to change for
the second and future scopes.


Good choice on scopes.....and clear skies.

P.S. I can picture you out on the moors (sp?)
now.  The wind blowing and the wolves howling.
Yea, that's liven.

Frank Ward

Atlanta, GA
75 degrees today and clear skies




-.........your msg...........................................
>1 typically, how thick is an 8" mirror ?
>2 does thickness have any bearing on the the mirrors performance or ease of
>manufacture ?
>3 does glass come in any particular grade which is more suitable for mirror
>making ?
>
>Jake
>Sauchen
>Scotland