Solar Filter Adapter for Camera or Telescope

Here's my take on a solar filter adapter for my camera/telescope. The OpenScad file is also included so you can adjust to fit your lens and filter sizes.

Key variables are :
lensDiam = 78; //actual diameter of the front of the lens, maybe a little smaller even so the lens sits against the faceplate rather than the filter itself
lensHoleDiam = 88+4; // the "88" is the actual diameter of my lens body, behind the front element and the +x gives room for foam tape around the inside
lensHeight = in*.5; //how tall should the lens surround tube be (.5 is bare min I think, .75 would probably be better)
filterX = in*4; //width of the filter film
filterY = filterX; //assumes square filter, but change if yours isn't

I used the 4"x4" filter from Thousand Oaks Optical https://www.amazon.com/gp/product/B00DS7IFQS which covers my lens with some room to spare.

Print 2 separate pieces, the front face and the back. The back is designed for some foam weatherstripping tape to be added inside to hold it onto the lens. It worked, but I didn't feel it was sturdy enough and rather than enlarge the back tube and reprint, I sewed together a spandex "sock" and attached it to the ring with hot glue. The sock just slides over the lens and holds it snugly, but it's easy to remove during totality.

To assemble, just put the filter into the front and set the back on. Mine was tight enough that it just clicked together, but I wrapped the edges in thin copper tape to make sure it stayed together if it got bumped and also to help reflect back some of that solar energy rather than cooking the filter too much.

Also, I added some thin weatherstripping