Three minor but frustrating differences that have caught me have been cosmetic issues, which don't really matter until they do.
I bought screws from a company for several years when suddenly they changed the head by adding some knurls to M3 socket head screws. A different set of Truss head screws had a small countersink type feature added around the torx drive. And then the finishing process changed. All subtle changes but when one screw out of 20 is different it stands out. My solution was to track batches of cosmetic screws and compare them before transitioning to the next batch. Leftovers go in a spare parts bag.
Interesting, what kind of workpieces do you make that you put that much attention to detail? Are these for display? Or is it just very high level of workmanship applied to otherwise normal articles?
This was for occasionally handheld measurement instruments. Ultimately it might be a little nit picky, but I figured if it was noticeable to me it might be noticed after a while by a user and then bother them. Some users would never notice but why risk it?
While thinking about what to do I went down a rabbit hole learning about clocking screws. I decided that was far from necessary but if I ever make something really nice for myself in metal with the right design I might give it a try.
Very much appreciated, I love such attention to detail and I would definitely notice and see it as a sign of dedication. Likewise flat screwheads lined up with the slot aligned with the edge that the fastener is nearest to. Old school marine woodwork with brass screws is done like that and it really shows off the workmanship.
Whoever worked on that church seems to have had the same idea :)
I bought screws from a company for several years when suddenly they changed the head by adding some knurls to M3 socket head screws. A different set of Truss head screws had a small countersink type feature added around the torx drive. And then the finishing process changed. All subtle changes but when one screw out of 20 is different it stands out. My solution was to track batches of cosmetic screws and compare them before transitioning to the next batch. Leftovers go in a spare parts bag.