Update on shutter repairs

After a serious series of testing the refurbished shutter modules I have learned more. There's another way for the shutter to fail, and it's sneaky. The shutter blades are very thin metal and they very quickly gnaw a bit of play around the slotted axel. There's also some slack on the planetary gear, and as a result the shutter can flop about a minute amount. The movement is very minimal, but with relatively small tolerance that's enough to cast a shadow on the edge of sensor, or have a tiny gap when closed. I wouldn't have noticed this less I had held the assembled camera in hand and looked in with the camera at the right angle. I tried a range of glues, but those didn't hold on the blade and tiny axel at all. I was running out of options when I realized the play isn't an issue, all I have to do is make sure the blades don't flail around out of position. The easiest way was to make a miniscule wavy bend on the shutter blades, so the friction of the shutter sandwich is just enough to resist the gravitational pull on the blades. After some trial and error on the test-rig I finally ended up with a friction brake that didn't hinder shutter movement even at the low-energy 2.5V 60mA pulses, yet prevented the blades from changing their angle on their own. As luck should have it, it's a clear night tonight. And not a single shutter failure, yet.

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