Solar Filter (Baader Film) for Refractor Telescope (80mm)

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Designed to hold Baader Solar Film as flat as possible for my RVO 60ED refractor. This has an 80mm diameter dew shield. The OpenSCAD files are provided so that you can modify to fit other telescopes. I made a matching storage box and lid, the film is delicate and needs protection when not in use. The lower box has ledges to keep the film away from the bottom of the box. Again the .scad files are provided if you need to modify. Note that for the box you would need to install the BOSL2 libraries if you are going to work with it in OpenSCAD. I printed the front piece in white PETG to reflect heat and be thermally stable. The back piece can be anything, I used black PLA which does not string between the castellations on my Ender 3 V2. The Baader film is really thin and delicate. Keep it between the supplied two sheets of tissue for cutting. Cut on a really flat surface. Use the back piece as a template and cut around it with a sharp scalpel. Offset the template by about 0.5 mm in X and Y directions so that your film square ends up slighly smaller. This way it fits the recess in the front piece without creasing. I printed a disc to support the film during assembly. Lay the front, face down on a flat surface. Insert the disc in the central hole. Pick up the film with a piece of paper (no finger prints!) and drop it in the square recess. Carefully lower the back piece ono the film. Push down firmly to keep the film flat and go to each of the 4 small holes with a sharp needle. Puncture the film multiple times around each hole. Then use a 3mm drill to clean out the holes. Bolt the two halves together with M3 screws and nuts. That's it. Keep the filter in its box when not in use so that it is protected from dust and physical damage. Always check the film for damage before viewing. Remember solar viewing can be dangerous without the proper precautions.