"Joseph Gwinn" wrote in message
...
In article ,
Gunner wrote:

On Wed, 19 Oct 2005 22:41:25 -0400, "Adam Smith"
wrote:

http://www.surplusshed.com/ consistently have used reticles at good
prices.
I haven't bought reticles, but I've bought other optical goods, they
were
very painless pleasant transactions. Next day shipping, perfect
packing,
prompt communications yada. I bought a reasonable condition coated 50
mm
objective (in cell) in the last purchase, and I think it was $7 or some
such
figure.

I recall that "Procedures in Experimental Physics" (the John Stong book
that
somebody mentioned earlier in the day: Lindsay) has a section on using
spider silk to make a reticle. I believe that most folks now stretch
single
polypropylene fibers.

(ping James Lerch, Bob May, other of the lurking ATMs?) anybody done
this?

I once redid a reticle using spider silk. It was actually quite easy
to do, using black widow silk..of which we have a rather large surplus
of here in the desert..

I used a tiny drop of airplane model superglue to hold each end of
both strands across the reticle ring, but it was a stone bitch getting
them perfectly oriented at 12/3/6/9 oclock and had to redo it about 10
times..and never did get it perfect, but shot the scope for about 10
yrs on a 243

Not having any inert gas (at the time)..it did fog on me once under
sever conditions. Normally they are nitrogen filled..I wonder if
Argon would work?

Yes. Nitrogen is used because it's cheap, but any inert gas will work,
if it's bone dry. Dry is the key.


Joe Gwinn

Yes, argon will work really nicely as an inert atmosphere inside your scope.
Even welding grade is still low in water content and was probably filled
from the same tank as the high purity lab grade bottles at the same time.
Just didn't get the price tag!

The argon will also allow a little more UV light to pass through the scope,
but when you allow for the distance to the target and the light path all the
way from there, you won't ever know the difference.

It's easy to rig up a fitting to your scope with a plastic bag, a pair of
scissors to snip the other end of the bag and a couple of rubber bands while
you complete the assembly of the scope. You can even use your welding flow
regulator to give you a nice steady flow to purge the lot. If you are going
to do it inside, allow for fresh air to breath for yourself. Oxygen
deprivation will just send you to sleep......

If you don't have spider webs available that suit, and the Americans made a
pretty fancy bombsight that was security classified during WW2 with spider
silk threads, you can make "stretched sprue" like most model aircraft makers
with a candle and a bit of spare sprue and a gentle pull.

Many other reticles are engraved or ruled into a piece of glass.

Hope this helps,
Peter