RE: ATM Wooden Tube

["Anderson, Jay" <andeja@mail.va.gov>]

Pedro wrote:

>I'm considering building a tube made of plywood instead of sonotube.  Are
>there any advantages or disadvantages in using this material? (I'm
>concerned about thermal currents inside the tube).  Its for an 8" f/6.

Consider Apogee's fiber reinforced thermoset epoxy matrix tubes.  They
are light and very strong.  You can stand on them and they will retain
their shape and are only about 1/8" thick (half the thickness of
Sonotube).  They won't dent like Aluminum either and thermo conductivity
is 700 times less than aluminum.  They have I.D. sizes ranging from 3.5"
to 20" for prices ranging from $10 a foot to $30 a foot.  You can get 6
feet of 14" tube for $120 ($20 a foot) plus $16 UPS shipping for a total
of $136.  I don't think this is bad since most of you sink some big
bucks into optical components.  Why not go all the way!!!

Pedro, your 8" f/6 tube would cost:  Using a 10" tube 4 feet long (48"
focal lenght)...  this would be $64 for the tube and probably $12 or
less UPS shipping for say... $76!!   Not bad.

Apogee can be reached at AstroSirPlus@il-icom.net       and
http://astronomy-mall.com
 ----------
From: Pedro
To: atm@shore.net
Subject: ATM Wooden Tube
Date: Monday, June 23, 1997 6:36PM


hi,



Thanks in advance...
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