I am in the process of trying to fix one of my camera lenses. The mounting rings are threaded in and have a notch on opposite sides that require either a special spanner or two crossed over screwdrivers to undo it. Of course the screwdrivers never work and I normally end up ruining the notches and scratching the lens.
This time I thought that I would do it properly and make a tool especially for the job. A couple of hours work and bits of metal that I had laying around produced the spanner shown here. I first needed the flat tips that are shown loose and today I made the pin tips that are fitted to it. I had to sacrifice a 1.5mm drill for the pins but it was well worth it. I can use it with every confidence that it won't slip and destroy the lens and can make new tips for any other sizes. I am going to add a threaded rod through the centre to make adjustment simpler.
