So, I got these great nail scissors from Brookstones. (You know, the little ones with the curved blades. The curve is hard to see in the picture.)
I use them to cut my nails.
They used to be perfect: when the handles were closed, the two points met, and you could cut really precisely. But after 6-8 months of use, they don’t meet any more.
What happened? Some kind of metal fatigue? Did the shape of the blades change? In what way? I used to be able to temporarily fix them by tightening the screw that holds the blades together, but no longer.
I should say that the blades still touch each other, and the screw is as tight as it gets.
Not really a physics question. It looks like the screw and the hole are wearing which changes the geometry. When the handles meet the worn pivot point no longer puts the tips together. It’s not a matter of tightening the screw because the wear isn’t in this direction. The only way around that would be a replacable pivot bearing or a pin that can expand to fill a worn hole.
You’re saying the hole is getting bigger and the screw is getting smaller? I think that’s plausible. But there’s no ‘wiggle’ and the screw still screws.
The screw is approximately midway on the blades; wouldn’t that mean that the give in the screw would have to be half the distance between the points? The points are like 2mm apart. Do you think there could be 1mm of give in the screw/hole match and I haven’t noticed it? I’ll check it when I get home.
If that’s the cause, can I extend the life of the next pair by oiling the screw better?
The catalog page says they are for cutting cuticles, not for cutting the nails themselves. If you are actually cutting the nails, you may have overloaded the blades and bent them.