3D Printed Solar Filter Attachment

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Skills: Solidworks, CAD, 3D Printing, Design, Tolerancing

Role and Background: 

This was a personal project that I designed for the upcoming eclipse, so that I could take pictures of the sun during the event. The idea was born out of the high cost of commercial solar lens, so I decided that I could just design a custom lens to fit my camera at much less cost.

Challenges: 

The main challenge was coming up with a design that I could insert the solar film into, while protecting the film and also have the design be able to be 3D printed. This was accomplished with the final 2-piece assembly that I designed. A secondary challenge was discovered during the assembly of the pieces, which was keeping the solar film from wrinkling. This was overcome by minimizing the surface contact between the two 3D printed components (but while keeping enough contact to secure the film in place).

Process: 

Since this was to be an attachment for my camera, the first step was to measure the diameter of the camera lens, and the dimensions of the attachment slot on the lens. From here I came up with a two-piece model, which was designed using Solidworks.

In the design, the bottom piece included the slot that would allow the lens attachment to screw onto the camera lens, while the second piece would sit on top of the first with a small gap designed between them for the solar film to sit.

The slot that screwed into the camera lens was purposefully designed slightly too thick to fit in the lens, so that I could manually sand down the slot until the interference fit between the lens and attachment was just right (I didn’t design it to the correct tolerance in Solidworks because slight variations in 3D Printing would make it hard to ensure a correct fit because the slot was only 1.45mm thick).

In the first iteration of my design, I attempted to use an interference/press fit to join the two pieces together using a indentation that would allow the top piece to “pop” into the bottom one. However, after 3D printing I found that the pieces were too stiff to force together, so the 2nd iteration of my design instead used glue to join the two pieces. This design worked much better, and was the final design that used when I went down to Oregon for the solar eclipse.

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Christopher Fisher