Wire for target scope crosshair

[graycrait]

I've got an old Redfield 3200 12x that a fella gave me and it has broken crosshairs.  Does anyone know of a source for .001" wire in relatively small amounts.  I'm too cheap to send this off to someone else when it looks like I can do the repair myself.    

[Jonnin]

well... you could catch you a brown recluse and ask it nicely for some webbing ... I think that is what older scopes used?

[maroonandwhite]

well... you could catch you a brown recluse and ask it nicely for some webbing ... I think that is what older scopes used?

Please video the encounter of you go this route.

 

Also I'm sure you probably searched but this came up in the first few links. It's 100' but I doubt you find a smaller spool of such a fine wire.

 

http://electrontubestore.com/index.php?main_page=product_info&cPath=57_1_8&products_id=1438

Edited January 18, 2013 by maroonandwhite

[Caster]

I know an old fella who replaced his with a hair from his grand daughter.  Young girls usually have very fine hair.  I wouldn't want the job of trying to get it in there straight though.  

[maroonandwhite]

I didn't even know it was wire in there. I always just thought it was painted on or something. I can imagine it would be a challenge to replace.

[Jonnin]

Hehe I think any spider web would do, but for some reason that stuck in my head as the one they used as it was finer, thinner maybe?

 

If you try it, be careful.  They are not as dangerous as you might think (timid, can't punch thru good clothing, and not really agressive) but if you do get bitten it can get very ugly in a hurry.

[mikegideon]

I've got an old Redfield 3200 12x that a fella gave me and it has broken crosshairs.  Does anyone know of a source for .001" wire in relatively small amounts.  I'm too cheap to send this off to someone else when it looks like I can do the repair myself.    

 

How do you get the Nitrogen back in the scope so it doesn't fog? I took one apart when I was a young 'un, and agree that repairing a reticle probably isn't a big deal. Installing the little windshied wipers after it's full of humid air is pretty tedious, though. :)

[graycrait]

Thanks for the tips and may have found a $15.00 source for .0005" tungsten.  Also I am going to buy a 100 page book on this subject.  Can't be that hard.  Also was wondering about purging with nitrogen also.  Hope to find that out too.  I could send the scope out and wait a year to get it back at significant cost or learn to do it myself.  Option 2 sounds cheaper when considering my time is pretty cheap.  

[mikegideon]

We keep tanks of nitrogen to pressurize transmission lines and waveguides. They're too big to carry around, but holler if you need a source. I have enough to blow out a few thousand scopes.

[graycrait]

mikegideon,

 

Thanks on the nitrogen offer.  

 

Already confirmed the ordering place for 10' of .0005" tungsten wire with some gent up in NY.

 

Craig

[graycrait]

Redfield 3200 12x crosshair and holder

[Caster]

Another option, stop by a machine shop and ask if they have a Wire EDM.  If so, ask for a length of scrap wire.  They range in size from .0015 on up.  THey sell the used wire for scrap but I'm sure they'd give a foot or two for nothing.  

[Dolomite_supafly]

I have used human hair in the past to fix cross hairs. Worked great.

Dolomite

[MacGyver]

Sounds like you've got it, Craig, but EDM wire is definitely what you want if you're just searching around the area.  Most tool and die shops would likely be glad to give you a couple of feet.

[Guest Lester Weevils]

I was gonna suggest maybe unwrapping a few coils of coated magnet wire from an old junk radio RF coil. Some of that stuff is real small diameter.

 

Astro telescope reticles for finder scopes are often etched on glass. A little bit of good clear plastic would work as good. I've made such reticles that seemed to work OK out of plastic. Used a straight edge and xacto knife to make the grooves, fill in with sharpie and immediately wipe off the excess left on the surface of the plastic.

[Dolomite_supafly]

I wonder if you could use a piece of glass and have it laser edtched with the reticle of your choice? It would just need to be a flat piece of glass with no curve to it.

 

Dolomite

[Guest Lester Weevils]

There's all kinds of potential. Illuminated finder scope eyepieces are just an etched reticle with side-lighting. For just a simple crosshairs you can do that in plastic with an xacto knife. Drill a side-hole to hold an LED, silver batteries and a simple rheostat circuit to adjust brightness.

 

My homemade finder reticle eyepiece was simpler still, but not ruggedized enough for a gun. Installed the reticle at the focal plane of a 25mm eyepiece, and drilled and tapped a hole in the eyepiece aluminum body. Made a little aluminum adapter that screws into the hole, with a hole in the other end big enough to hold the head of a 1AA mini-maglight pocket light. Which is too bright for nighttime use, so I poked a couple of pieces of red plastic picnic cup down in the adapter to attenuate the brightness and make it illuminated red.

[graycrait]

http://www.youtube.com/watch?feature=player_embedded&v=65Q-2E6Tz7M

 

Also some folks like a strand of Kevlar from fishing line.  I think I am going to use dental floss as my reiticle holder has the grooves just like in the video.  If it doesn't work it is an easy refix with some other material.

[MarkInNashville]

When I was in the Navy, we had optics that were outside at all times. We had to use ultra-pure nitrogen to pressurize them. As I recall being ultra-pure, it was much drier (thus lowering the dew-point) and had been filtered better for particulate matter. I agree that anything you can do, on the cheap is much more satisfying, and probably quicker, than sending it off.

 

Just wanted you to be aware.

[Jonnin]

we do some work like that here.  We operate the item in a vac chamber, removing *most* of the air, then fill with gas, reassemble and seal, and its done.  It is not difficult to do this, you just need a vac chamber that lets you handle the item enough to reassemble it.  I do not know if you can do this easily at home, but it seems possible to me --- my wife has a vac sealer for food, mabye can modify one of those to do it?  Dunno where you would get a can of nitrogen either (?) but that is a harmless gas should be possible to buy one.

[Jonnin]

I wonder if you could use a piece of glass and have it laser edtched with the reticle of your choice? It would just need to be a flat piece of glass with no curve to it.

 

Dolomite

I have often wondered WHY this is not how they were made.

[Guest Lester Weevils]

I have often wondered WHY this is not how they were made.

 

Making the characteristic wild guess-- Nowadays anti-reflection coatings are so good that you get near perfect transmission thru large numbers of lenses, but in the past they may have wanted as few pieces as possible in the optical chain, to maximize thruput?

[Jonnin]

Making the characteristic wild guess-- Nowadays anti-reflection coatings are so good that you get near perfect transmission thru large numbers of lenses, but in the past they may have wanted as few pieces as possible in the optical chain, to maximize thruput?

 

yea I meant the modern lower end scopes, I would think it would be a way to cheapen em up another notch.