[tempestwizz (Brian)]

Over the years my favoured eye has developed astigmatism. As a Televue user I have purchased an appropriate value Dioptrix filter/lens that will attach to a number of the wider angle eyepieces. I find that it improves my viewing experience significantly.
However, it can become tedious moving the filter to alternative lenses, especially in the dark.
I also have some Nagler type 6 lenses that I use throughout the night. While TV do make an adapter that will fit the Dioptrix to the Type 6 eyepieces, it is still fiddly, and not inexpensive.
To address these issues I have come up with the idea to fabricate an aluminium sleeve that will fit over the narrower eyepieces and hold an optical astigmatism lens used for eyeglasses on top of them.
The astigmatism correction lenses that I sourced are 36mm diameter.
Now I can just lift off or on the correction lens to any of my narrower eyepieces effortlessly. Simply rotate the whole assembly to achieve best clarity. The lower retaining flange sits on top of the rubber cup and rotates on it. The arrangement may restrict the available viewing angle in the case of the Naglers, but there is still a reasonable area that can be seen.
This concept can fit any of a number of eyepieces. It would also facilitate some one carrying this adaptor with them and just drop onto a colleagues eyepiece when group viewing without disturbing the setup.
I’ve made my sleeve to accept 43mm outer diameter eyepieces, and (now) without eyeglasses, there is plenty of eye relief.

Fabrication is relatively simple if you can access a lathe and get a bolt of aluminium. Some of the plastics would also be suitable, I happened to have some aluminium already.