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Re: Sextant octant rubber eyepad preservation
From: Brad Morris
Date: 2019 Aug 15, 14:12 -0400
From: Brad Morris
Date: 2019 Aug 15, 14:12 -0400
Ed,
My experiences with rubber are neoprene, as in wetsuits, that extends backwards decades.
What I have found is that the neoprene oxidizes and becomes brittle and crumbly. What used to be dynamic and flexible is no longer that. Instead of stretching, it tears. There is no cure for oxidation.
Your eyepieces will be more durable than a wetsuit, of course, as the material is much denser. Likely not neoprene, but oxidizing none the less. Greg's advice will limit the oxidation, by forming a film barrier between the atmosphere and the cup.
Have you considered making casts of the existing cups and making replacement cups from them? Shouldn't be overly difficult with some plaster and pourable plastic. You can retain the original parts as an antique, but gain the utility of a new eyepiece. Just a thought.
Brad
On Thu, Aug 15, 2019, 2:03 PM Ed Popko <NoReply_EdPopko@fer3.com> wrote:
Greg,
An interesting recommendation. I have one, and have used it on my car's vinyl dashboard and door skirts. But I never thought that it did more than help get dust off the pebble texture surface and put a low-gloss film and 'new car smell' over things.
Ed
