Strange mechanical theories?!?

That's funny.

 

I heard this tip from an old machinist and thought it was a bunch of BS because it didn't seem like it could be true. He said when you're tightening a Jacob's chuck with a key, you should put the key in one hole and tighten it, then rotate the chuck 120 degrees to tighten it from the second hole, then rotate it 120 degrees to do the third hole. You're spinning the same part of the chuck with the key no matter which hole you put the key in, so it sounded like some old wives tale. But I started doing it that way for kicks and IT'S TRUE. I can't explain why, but when you rotate the chuck and put the key in the next hole around, it tightens a little more, then it tightens a little more on the next hole. It holds the bit tighter when you do it that way compared to tightening it from just one hole. I think the ring part of the Jacobs chuck must have some slop or wobble in it, and it sort of wobbles off center as you tighten it from one side, and going around to the next hole takes up some slop somehow. You can definitely get the bit tighter by going around to the next hole. It seems to defy logic.

Most people you tell that to will think you're nuts or stupid, but try it yourself and I think you'll find it really works. The more old and beat up the chuck, the more it's true I think too. Anyone else tighten their Jacob's chuck like that?

 

Thanks for the explanation, but even at 16, I wasn't stupid enough to believe that one. Anyone that's driven a car more than once should be able to see the perverted reasoning of it.

 

One of the first things I learnt from an oldtimer when a T&D apprentice., The old guys usually didn't want to tell new guys anything. And it works on lathe chucks, too.
I usually don't do it unless I get a slip, then go back and tighten all three and good to go.

Frank

 

Yep.

 

Well, yeah, if it's falling straight down, like if the wings came off or something. But the same thing will happen in a rotor wing if the rotor comes off.

 

Me too. Absolutely true. The 3 jaw chuck in the lathe too.

 

Yep, I think it tells you to in the instruction manual.

 

Oh, and you need not know how something works to fix it. I worked in a GM dealership for 13 yrs. Most of the guys that work there have no knowledge of mechanical principles. They replace the parts that the other guys replace and if that don't work they put the car outside until the boss gives it to someone who actually can diagnose it. The first guy then goes on to an easy job like brake pad replacement and makes a boatload of $$$ while the guy who is good gets peanuts for his knowledge. Therefore you can fix cars without knowing how they work.

 

We have a winner. I just shot milk out of my nose

 

My former boss was certain that if you didn't turn off a power point before you yanked the plug the electricity would leak out. And that would cost him money.

 

From what I understand this is sorta kinda true in some cases.. Because some of the new cars run adaptive ecus (computers) that tune themselves to run the best with local crappy fuel and driving style. That said I'm fairly sure they all reset with a quick battery disconnect for a minute or just changing your driving style for a while.

*Please note I know more about suspension(mostly rally at that) in new-ish cars then motors.*

 

Sounds like the guy who called for a replacement part for his computer. "The cupholder broke." Turns out he didn't have a clue about CDs, and was ejecting the CD tray and using it as a cupholder.

 

Apparently some folks think sand works well on Audis...

http://www.audiforums.com/m_693578/mpage_1/key_/tm.htm

Hard to tell if this is a goof or the real deal. OP poured "about half of a 25lb bag of sand" into his running Audi turbo to port it.

 

It gets better, you used to be able to buy a Lucas Smoke Leak Detector for electrical diagnosis. I have my nose, I just sniff around for burnt wires when something quits working.

 

It won't ping, but it will diesel from the exhaust valves and plugs running hot. Plus the throttle blades will need to be higher to even run. If there is any fuel there it will diesel until it is gone. A Qjet with leaking well plugs and a smogger timing curve, I would think you could set a Guiness record on dieseling at 8:1. When you retard it to an extreme degree the mixture is still burning in the exhaust port, and the motor will run really hot. If you are going for an emissions test, retard your timing as far as you can get away with, it will burn the paint off of the inside of your tailpipes.

 

http://www.mototuneusa.com/break_in_secrets.htm