I hate to break it to you, but the lug nuts on Plymouth cars (at least those of a certain vintage) are threaded backwards on the right side of the car, in order to reduce the likelihood that road vibration and the constant spinning of the tire to the right would loosen the lug nuts.
My brain hurts.
I actually have a little box of stainless steel 1/4-20 hex nuts on my desk, just for special occasions. They have a left-hand thread. True story.
I much prefer the term sinister, it’s just so much easier than left-handed.
Let’s not forget the flush handle on your toilet. It only takes one time cracking your toilet tank for you to learn that it’s a left-hand thread.
Some older automobiles had reverse threads on the lug nuts or lug bolts. Old VWs and some others had this. The idea was that on the left side of the car, righty-tighty would help keep the nuts/bolts tight, due to the direction of the wheel travel. And on the right side they might loosen up.
I’m a lefty too, and I didn’t really understand his explanation either - perhaps because my first question is why would I be doing it with my right hand… Generally speaking, clockwise tightens and counter-clockwise loosens, though.
A third category is screw-on connections that are designed to be incompatible, so they don’t get connected by mistake. That’s why gas tanks for flammable gases use left-handed screws on their connectors, while inert gases have right-handed connectors. It would be rather dangerous if you tried to do inert-gas welding, and used a bottle of acetylene instead.
Yet another place you see reverse threads is on turnbuckes. One side has a reverse thread, so when you rotate the buckle, the two screws move in opposite directions.
Interesting thing about bicycle pedals is, if you look at how the pedal rotates relative to the crank, the left side pedal rotates clockwise, and the right side pedal rotates counter-clockwise. So why is it the left pedal that has the reverse thread? Precession. (Just look at the animation on that page, I can’t describe that with words.)
That’s pretty interesting (I had to stare at that animation for about 18 hours until it sunk in).
Great examples! I didn’t know the gas tank one.
Turnbuckles, yes, and a few related devices, such as jackscrews. I think there are such devices with narrow curved saddles on each end which one can use to force pulleys further apart, to tighten the belt. The threaded rod on some scissor jacks does this (though some only have one set of threads). I wonder, do automobile tie rods do this to allow wheel alignment?
I have a take-down putter much like this
that is reversed threaded since a right-handed person using it would cause it to unscrew as he/she hit the ball.
(I spend way too much time around amusement parks with mini-golf courses)
Yes, many cars do. Just imagine the buckle on a turnbuckle being a sleeve with interior threads.
As everyone knows, the preferred terms here are deasil and widdershins.
Imagine you are holding a bottle of Coke and you want to take the cap off…what direction do you turn? If you’re like most Americans your hand already knows how to do this without your conscience input. Simply rotate your imaginary bottle of Coke so that the threads line up with whatever you are trying to (un)screw
The problem with left threaded screws is finding a left handed screwdriver.
I don’t like the whole “righty tighty” thing, because if I’m tightening a nut or bolt more often than not I’m going to place the wrench horizontally and push down to tighten. If the bolt is above my head I’m going to have the handle pointing down and push left to tighten.
I thought you were pulling our legs with some obscure joke but nope. I’m guessing I probably won’t learn two more words today so thanks for increasing my vocabulary today more than everyone else in the world put together!
I keep those in the vertical drawer, right next to the metric crescent-wrench.
I learned from my grandfather that the LP threads on a trailer are left-handed so you can’t accidently thread them to the water lines.