Re: ATM new minimalist 16 inch with sliding focuser

["at making" <atmaking@hotmail.com>]

Hi Shane,

If you love "classical design" but want to have a lighther scope, the 
solution could be to use doorskin of foam "ala Steven Overholt". The ratio 
weigh/rigidity is great. That cost much less than composite (fiber+epoxy) 
but it could be part of your solution. It' mean more works than with a 
single panel of plywood because you got to cut many more parts. I don't know 
what could be the weight of the part but that could be close to the weight 
of a single 8 mm panel but with the rigidity or a much larger one.

Frédéric Géa
http://astrosurf.com/altaz/index_e.htm


>From: "Shane LaPierre" <shanelapierre@hotmail.com>
>Reply-To: "Shane LaPierre" <shanelapierre@hotmail.com>
>To: atm@shore.net
>Subject: Re: ATM new minimalist 16 inch with sliding focuser
>Date: Thu, 31 Jul 2003 11:27:06 -0400
>
>
>No criticism meant at all, but one thing that has caught my attention 
>everytime I consider redesigning my 20" is that it's difficult to shed the 
>mass.
>
>My current 20" has a 50 lb mirror, and I was only able to shed about 20 lbs 
>from the OTA itself when considering a minimalist design (my current OTA 
>weights in at 121 lbs.).  I have not found the benefits of shedding 15% to 
>20% of the weight to pay for the features I have come to appreciate in the 
>typical mirror box, truss, secondary cage alt-az.  Some of these benefits 
>include simplicity of design and construction, rugged housing of the 
>components, protection from the environment during observing and maybe a 
>few others. Anyway, these are simply my priorities, but I have always felt 
>underwhelmed at the end result of a minimalist telescope that weights in at 
>only slightly less than the current modern Dobsonian.  I certainly see 
>better results in using ultra-thin mirrors.... but that seems to bring up a 
>new set of issues in the 1/2 meter class.
>
>On another note I haven't posted here in a while because I don't get to ATM 
>too often.  I think this coming weekends visit to Stellafane has me primed 
>a little more :)  I will post pictures after the event at my website below.
>
>Shane LaPierre
>http://www.ct-astronomer.com
>
>
>>From: "Mel Bartels" <mbartels@efn.org>
>>Reply-To: "Mel Bartels" <mbartels@efn.org>
>>To: <atm@shore.net>
>>Subject: ATM new minimalist 16 inch with sliding focuser
>>Date: Tue, 29 Jul 2003 23:24:14 -0700
>>
>>
>>http://monroe.ca.campusgrid.net/home/Classroom+Pages/Mathematics/Mr.+Martinez/Telescope.html
>>
>>Ron Martinez' 16 inch
>>
>>
>>
>
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