Apology in advance because this is not automotive.
In the mid 1970s, in high school, I worked in a neighborhood TV repair shop.
Lady had a 21 inch B&W (Zenith IIRC) set brought in with a worn out CRT.
Picture dim and fuzzy.
She opted for a new (vs rebuilt) tube, and a fine example it was.
We got everything set it up real nice, for a 10+ y.o. set.
She complained about the much more visible raster lines.
This was a big set for the day.
Unfortunately, there was no adjustable focus.
I wanted to tell her just donāt watch it from 6 inches away.
The left-handed studs on those old Chrysler products previously mentioned were also marked the same way. You just had to have enough sense to look for it.
In the 1950s quite a few vehicles used left hand threads on whichever side was appropriate; My memory was the Ls were on the R side like bicycle pedals though.
It was to keep the lug nuts from unscrewing themselves while the vehicle was moving . The right side nuts have left hand threads so they would tend to turn in a counter clockwise direction and the left side nuts would tend to turn in the clockwise direction if they came loose.
Thatās my memory too, snapping off a Dodge stud at the gas station from the right side of the car. But all the sites I now find state the left hand studs were on the left side of the car.
I guess the reverse threads were a good idea in theory as they wouldnāt naturally loosen due to tire rotation if left a tad too loose. Of course the problems described are why they are not used anymore. Also, I wonder how many times a lug nut got mixed up and people stripped the nut or stud.
Also, the internal fitting on a propane tank is reverse threaded and the external fitting is normal right hand threaded. I donāt know why this is done but all modern tanks with with both types of fittings while older ones only had the internal reverse threads. At least this isnāt something you can easily mess up because the fittings are so different.
Kinda like the person with the Corvette that complained it burned rubber if you floored it! I remember seeing that here once and wondered if it was actually real or not.
I have a funny story related to a younger friend of mine. He bought a decent looking 2007 or 2008 Malibu for like $3000 at an auction before the pandemic prices went wild. It was his first real car so guess having a few incidents is normal. Apparently the younger generation thinks texting and driving is OK so ran over plenty of curbs. At least three of his rims were all bent and there was a shake going down the road. His plastic wheel covers were also pretty cracked up and bad looking.
He also got some garish orange advertising wrap put on his car (not a scam) for some out of state college. They paid him like $250 a month as long as he drove X miles and tracked this using an app on the phone. Well this wrap started to peel and got even worse looking with time. He also managed to crack some trim pieces which was more apparent because of the wrap.
One day he called me because he had a flat tire and didnāt know how to change it so I went over there. He had been texting and ran over a curb at a pretty high rate of speed. One of the tires had exploded with a loud bang like a gunshot and there was a major square kink in that rim the shape of a standard street curb. The tire and wheel were trash.
I am standing there staring at this car with an ugly wrap peeling off, trim pieces cracked and loose, a destroyed tire and rim, and other bent rims with the plastic wheel covers hanging off and broken. At this point he tells me āMy car was actually pretty nice when I first got itā and my response was āWell you sure took care of that!ā He didnāt quite know how to take that.
Then his dad calls while I am there putting the spare on. I could tell his dad was terrified of this guy trying to do anything to his own car and I let him know I had done this plenty of times before.
No one had the rims and he needed to go like 100 miles the next day. I called around to several places and finally found a really low-end used car lot that is indistinguishable from a junkyard and he got used tires and rims for like $40 that got him where he needed to go. He did end up getting a new set of tires the next day.
Then all the crazy accidents started that were no fault of his own. People kept running into his car. Some were hit and runs. One was a guy avoiding getting crushed by a semi so he ran into my friendās car instead. By that point my friend didnāt even care and didnāt want insurance money or anything.
Then it went in for an oil change and the shop basically said there was no oil in the pan and it was burning it. They told him to come back in two weeks and the level was half down from capacity. He traded it off and got $500. Basically the mechanic and the dealership told him the car was crap and to just give up on it which he did. So far the new car has been doing OK but it seemed like the old one was cursed.
Iād have to find my list, somewhere in the tool box area, but I know one of the others is a nut-like thing you have to unscrew to disassemble the freewheel.
Iām certain that itās the right hand pedal that is left hand threaded on bikes. Iāve repaired dozens of lower cranks on all kinds and sizes of bikes in recent years.
Thereās a sticker on each of my bicycleās pedals showing the rotation direction required. But the sticker doesnāt say whether that rotation direction is for installing the pedal, or removing it. So the sticker isnāt of much help, other than to remind the diyāer it might be left handed ā¦ lol ā¦
Another use of reverse threads is on the fan shaft of most window air conditioners. One motor has a double-ended shaft coming out for the fan over the evaporator and condensor coils as a way of making them more compact and lowering the cost. I donāt remember which one but one end of that shaft is reverse threaded for the same reasons being discussed here.
