RimfireCentral.com Forums - View Single Post - Scope lens internal "smudges"
View Single Post
  #8  
Old 05-10-2021, 07:16 PM
Etpm

Join Date: 
Oct 2015
Location: 
Whidbey Island WA
Posts: 
183
TPC Rating: 
0% (0)
The refractive index of argon is very close to that of nitrogen. Nitrogen must be used as a purge gas because it is so abundant in our air, since our air is about 80% nitrogen. Argon however is very common in weld shops. I have 3 large cylinders in my shop and welding is just a small part of my business. You could remove the lenses in question, clean the fungus from them if possible, and then put the scope with the lenses removed into a large Ziploc bag. Take it to a local welder and have the bag inflated. Let it sit for a few days to let the gasses mingle completely, take it to the welder again, squeeze the gasses out, and have the bag filled again with argon. Do this a few times and then screw the lens back in, keeping all parts in the bag. In order to make this worthwhile the lens cells must be sealed. The whole scope must be able to be a sealed unit. And looking online will provide the info for removing fungus from optics. If someone came to me at my shop I would not hesitate to fill several gallon sized bags with argon just to see if the experiment worked as planned. Argon used for welding is at least as dry as nitrogen used for putting.
Reply With Quote