The world has a lot of different standards for a lot of things, but I have never heard of a place with the default screw thread direction being opposite.
So does each language have a fun mnemonic?
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A nice thought until you run into a left handed thread…
Or when you’re screwing in a screw from behind/under something while lying upside down using a ratchet with an angled extender and you aren’t sure which way is actually left/right where the screw is.
Got that tee shirt too!
It’s works most of them time unless you’re in a specialty trade making spindle, gears, and such that must be threaded backwards to avoid the wheel undoing itself.
Yep, 80% of the time it works every time!
The point is, if you fix things, you WILL run into left handed threads at some point. I’ve found them in washers, vacuums, blenders, bikes, and cars. Left handed threads aren’t the most common thing, but they are out there waiting to screw with your mind and ruin your day…
Or you work with gas cylinders.
I don’t understand this one, please Airgas
I heard from a gas guy that this is to ensure that only connectors made for gas usage are used and people don’t build crazy contraptions with plumber gear for flammable gases… Kinda makes sense.
Reverse threads on gas cylinders are (as far as I know) only used for flammables.
I was sure there was a reason, I just never worked in the field long enough to learn or ask why
Thanks 🫡
They’re made that way so you don’t accidentally connect a gas cylinder to a water line.
Fucking facists keeping me from tap en flambé; like they know what is safe.
And you feel so incredibly dense every time you run into it and you can’t figure out what’s going on. The crank on my kids bike was out of whack the other week and I kept tightening it down and it kept coming back loose. I was turning the crank one way to tighten it which was pushing it against the lock nut but it needed to turn the other way to be pushed against the bearing before I tighten the lock nut down. If it was all right-handed it would have been clear what I was doing.
Spindles and shafting are places you can find left handed threads. And it depends on the direction of rotation like that bike crank. Can’t have things coming lose due to the way bike cranks turn, so they a left handed thread to stay tight.
It took me a long to time learn that when dealing with such things that I need to stop, look, and think about how things are assembled and why.
… and you hope you don’t forget until the next time you have to do it…