Leica M4 Eyepiece Cover
thingiverse
The cover for the metal eyepiece of the Leica M4 requires a decent fit, and I think using a rubbery filament would work pretty well. However, it seems someone has already created that design. My version is intended to be printed in PLA on a raft, which allows the outside portion to come off the print bed with a curved edge instead of being flat as a pancake.
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