Lens hood with hinged cap for Sigma 10-20mm F3.5 EX DC HSM

thingiverse

This lens hood with spring-loaded hinged cap has two key benefits over standard snap-on lens caps: - opening and closing happens at lightning speed - no need to worry about what to do with the cap while taking pictures. This model is designed for the Sigma 10-20mm F3.5 EX DC HSM wide-angle lens. The hood shape is a precise copy of the original hood and it attaches using the same bayonet system, either with the cap opening up or down. I prefer the latter because it eliminates having the shadow of the cap in the picture when shooting with the sun behind me. Instructions: The assembly requires: - two M2 screws for the hinge (the other end of the arm is glued to the cap) - a helical spring (I cannot provide sourcing information as I used what was available at hand). Its approximate dimensions are: - outer diameter: 6mm - loops inner diameter: 5mm - length: 25 mm between loops center when the cap is closed (so the spring should be shorter to ensure that there is some tension to keep it closed) I printed it in ABS, with three perimeters, and supports for the hood and arm. However, I think PETG would be stronger due to its better layer adhesion. PLA also works but may cause higher wear on the bayonet system. The tolerances on radii are very important for a good fit, you may need to adjust some values depending on printer / print settings.