Telescope
This was a project I did in Sixth Form.
Due to my keen interest in Astronomy and Engineering, I decided to research and construct a telescope myself. After learning a bit about optical design, it was a mostly mechanical project to build the truss tube and 3D print some parts.
I gained a lot of practical experience in using a variety of hand and machine tools.
I have been quite nervous during the building process, as there was no way for me to know if I did everything right. In the end, it actually surprised me how well it works when looking through the eyepiece for the first time!