Re: ATM Re: string spiders

[Daniel Fundo <fundo@bellsouth.net>]

<< In order to test the minimum diameter of the guitar string for my 3"
secondary (rebuilding of my 13" f/4.5) , I've tried strings of 0.008" ,
0.010" and 0.012".
Both the 0.008" , 0.010" broke. It seems the 0.012" is the limit to
avoid breaking of the wires for my 550 g mirror, but I'm pretty sure the
0.010" could be use for a 10" or less telescope >>

Raphael, I had the same problem when I used some 0.010" wire of unknown
type.  There are several different strengths out there. Stainless type
304V has a tensile strength of only 135,000 pounds per square inch,  
Stainless 316V is 220,000 Lbs/sq.in.,  Stainless spring wire 17-7 PH is
around 335,000 Lbs/sq.in., and stainless 18-8 (what I use) is 282,000+
Lbs/sq.in. (All of these numbers are from the Small Parts Inc. catalog
#18.  You can get the 18-8 in 30 ft. coils for $1.95. (standard
disclaimer)

I don't know what type is used for guitar strings, but once you start
handling them, they begin to weaken.

Someone mentioned once about painting or dulling the wires.  All you
have to do is get a little human sweat and body oil on them and they
will dull very nicely!!!

*****-----
Dan F.
Secretary/MAS
Memphis, TN