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View Full Version : Physics Question for 84 Dave!



Rtruck
03-10-2012, 08:36 AM
Ok Dave, had my car on the lift yesterday with all the wheels removed. The lug nuts were on the studs, screwed down to almost flush with the top of the lugs. Ran the engine for about 20-25 minutes. The right side lugs starting dropping off and the drivers side screwing down to the hub! Never noticed this before, but then I normally have the wheels on when running the thing on the lift. What is going on here? Figured this would be right up your alley!

empiretrucks
03-10-2012, 05:10 PM
Was it in gear? I know on some old trailers, the lugs were reversed thread because on one side because the rotation of the tires would supposedly back the lugs off. It would make sense if your car was in gear and the axles were spinning. While the axles are rotating, the lugs would want to stay in the same position. It's kind of like "an object in motion wants to stay in motion. An object at rest wants to stay at rest" The lugs want to stay "at rest", while the axles are beign forced to move. Since the lugs are loose, and not stuck in position, they will fight to get up to the speed of the axles. By staying as still as they can, they will actually unscrew themselves on one side, and tighten themselves on the other.

Rtruck
03-10-2012, 09:06 PM
No, not in gear and I noticed it happened on the front spindles. Didn't check the rear. But not in gear.

Racedad
03-11-2012, 09:05 AM
"Vibration refers to mechanical oscillations about an equilibrium point."Wikpedia.
Your spindles vibrated at their natural frequency that really got going with no weight on them. The threads have a clearance of a few thousandths,so as the oscillations had the nuts taking off and landing many times per second with some small degree of movement every time.The vibration has a similar nature on both sides of the car with it not caring about loose or tight,just clockwise or counterclockwise from the same vantage point which if you pick one will result in loosening on one side and tightening on the other.

84Dave
03-11-2012, 11:21 AM
As a practical matter, I can't add much to the above responses. EXCEPT........ I feel your very recent lug-nut observation was likely caused by the sun Solar storm that earth has experienced over the last 72-96 hours. During that storm, it is known that the magnetic polarity changed at least twice. That is, the waves from the sun switched north & south poles. And as our earth poles are a constant polarity, that sun-wave polarity change can wreak havoc with the sub-atomic metalic properties of earth metals. So..... I suspect if you had repositioned your race car 180 degrees on the 'run stand', you would have observed a constant directional CW or CCW rotation of the lug nuts on BOTH sides of the vehicle. That's my story & I'm stickin' to it! -Dave-

Tojo
03-14-2012, 01:21 AM
Dave....will you share some of what you are smoking????
Joe

84Dave
03-14-2012, 08:54 AM
Oh, NO........ NO!! It makes ones mind disfunctional ! LOL! -Dave-

car62
03-15-2012, 10:27 PM
For those of you who have never had the chance to meet Dave in person...you dont know what you are missing.

I was fortunate enough and had the chance a couple years ago...this guy is a wealth of knowledge!!!

dannyracer6
03-16-2012, 02:00 PM
eric, Call me..You have my number I think. I sent you an e mail.

car62
03-16-2012, 09:04 PM
i dont have your number...my new phone met some water,i just got the replacement today...feel free to give me a call at 208-625-1528

i just got home,will go check email now.