Lens alignment gauges beat feeler gauges on a Canon FD rebuild

I spent last Tuesday regrinding a Canon FD 50mm mount that had a slight tilt. I usually use feeler gauges to check the flange distance, but this time I borrowed a proper alignment gauge from a friend in Pittsburgh. The difference was night and day. The feeler gauge method took me about 3 tries and I still had a soft corner. With the gauge, I got it spot on in one pass. The gauge cost my friend like $180, but it paid for itself on this single job. Anyone else find that dedicated alignment tools are worth the money for older lenses?

2 comments

2 Comments

julia_anderson14d ago

That line about the gauge paying for itself on a single job really hit home for me. I had a similar thing happen with an old Minolta where I kept getting a soft spot on the left side no matter how careful I was with the feeler gauges. Borrowed a collimator from a local camera club member and fixed it on the first shot, which was honestly kind of annoying after all that fiddling. Dedicated tools like that feel pricey until you count up the hours and frustration they save. Now I'm slowly grabbing used alignment gear whenever I see it at swap meets, even if I don't need it right that second.

blair_martin14d agoMost Upvoted

You ever notice how the right tool just makes you want to kick yourself for not buying it sooner? My buddy Dave had this old Canon FTb that was front-focusing like crazy. He spent three weekends shimming the mirror box with random washers and foil, still couldn't get it right. Finally caved and dropped sixty bucks on a used focusing screen jig from some estate sale. Fixed it in ten minutes, and now he swears the thing paid for itself every time he shoots a roll. He still brings it up, like it's some trophy.