3 ms·

> You don't have to apply force in any different direction if you put scissors with symmetric handles in the wrong hand. [...] But that's not the same as needin

by jasode 4y ago

> You don't have to apply force in any different direction if you put scissors with symmetric handles in the wrong hand. [...] But that's not the same as needing to apply force any differently. For precision made scissors with tight tolerances at the pivot joint and sharp blades (premium brands like Kai, Gingher, etc), it will cut with either hand. But for scissors with a loose rivet (like cheaper scissors very common in kids' schools), the gp (ianferrel) you replied to is correct: the blades will not close tightly if the wrong hand is used to squeeze. The loose rivet scissors in the wrong hand will fold the paper instead of cutting it because the natural finger-closing motion will spread the blades apart creating a tiny gap instead of making them touch. Here's a 1-minute video that tries to visually explain what a left-handed person struggling with a right-handed scissor experiences: https://www.youtube.com/watch?v=wyGCvSCnkWk https://www.youtube.com/watch?v=wyGCvSCnkWk

BugsJustFindMe 4y ago
It sounds like you and they have decided that a human hand scissoring may only push inward or outward or neither using one side of the hand but not the other. That's not true about hands or about scissors though, even poorly constructed scissors. Your thumb and fingers of both hands are equally capable of producing both separating and joining force while closing. You and they have just decided that curling your fingers and pushing your thumb outward is right and the opposite is wrong, but the opposite works too. The scissors don't care and hands support both.
- jameshart 4y ago
  The grip strength of curling your fingers into the base of your thumb is stronger than the pinch strength of pressing your thumb against your fingers. Scissor ergonomics aligns the handles so applying the finger-to-base-of-thumb grip to the handles (with the upper handle pressed against the outside of your thumb’s knuckle) pulls the blades together. In order to do that, scissors have to be designed to fit either a left or right hand. To use scissors wrong handed you have to catch the outside of your finger knuckles against the lower handle and pinch the upper handle down with your thumb.
cbm-vic-20 4y ago
TIL: I've been using scissors wrong my entire life. I didn't realize that you need to push the handles to apply lateral force to the blades to make them slide against each other, the more the better.
- anyfoo 4y ago
  Sorry for asking, but isn't that... obvious? So obvious that I bet most people just don't think about it consciously at all. If you don't do that, they don't cut properly, but it's likely to be something that the brain sorts out for you without you realizing the forces you apply.
- ianferrel 4y ago
  You probably haven't been. You probably learned it with muscle memory as a kid and just weren't aware of it. I wasn't aware of it until I was in my late 30s and was helping my kids learn to use scissors.
nyanpasu64 4y ago
And for the average scissors I use, it won't cut properly in either hand. Interestingly haircut scissors are better at cutting paper than regular paper scissors! I tried disassembling a pair of haircut scissors, and found the screw is interestingly rotationally locked to the blade next to the nut (rather than screw head), and the nut has a spring-loaded locking mechanism (a planar version of mouse wheel notches) so it doesn't rotate unless you turn the nut with a large amount of torque.

by jasode 4y ago

BugsJustFindMe 4y ago

It sounds like you and they have decided that a human hand scissoring may only push inward or outward or neither using one side of the hand but not the other. That's not true about hands or about scissors though, even poorly constructed scissors. Your thumb and fingers of both hands are equally capable of producing both separating and joining force while closing. You and they have just decided that curling your fingers and pushing your thumb outward is right and the opposite is wrong, but the opposite works too. The scissors don't care and hands support both.

jameshart 4y ago
The grip strength of curling your fingers into the base of your thumb is stronger than the pinch strength of pressing your thumb against your fingers. Scissor ergonomics aligns the handles so applying the finger-to-base-of-thumb grip to the handles (with the upper handle pressed against the outside of your thumb’s knuckle) pulls the blades together. In order to do that, scissors have to be designed to fit either a left or right hand. To use scissors wrong handed you have to catch the outside of your finger knuckles against the lower handle and pinch the upper handle down with your thumb.

cbm-vic-20 4y ago

TIL: I've been using scissors wrong my entire life. I didn't realize that you need to push the handles to apply lateral force to the blades to make them slide against each other, the more the better.

anyfoo 4y ago
Sorry for asking, but isn't that... obvious? So obvious that I bet most people just don't think about it consciously at all. If you don't do that, they don't cut properly, but it's likely to be something that the brain sorts out for you without you realizing the forces you apply.
ianferrel 4y ago
You probably haven't been. You probably learned it with muscle memory as a kid and just weren't aware of it. I wasn't aware of it until I was in my late 30s and was helping my kids learn to use scissors.

nyanpasu64 4y ago

And for the average scissors I use, it won't cut properly in either hand. Interestingly haircut scissors are better at cutting paper than regular paper scissors! I tried disassembling a pair of haircut scissors, and found the screw is interestingly rotationally locked to the blade next to the nut (rather than screw head), and the nut has a spring-loaded locking mechanism (a planar version of mouse wheel notches) so it doesn't rotate unless you turn the nut with a large amount of torque.