h a l f b a k e r y
Think of it as a spell checker that insults you, as well.

meta:

account: browse anonymously, or get an account and write.

 user: pass:
register,

# Rocking car jack

Jacking a car by rocking it.
 (0) [vote for, against]

Can 4 guys flip over a parking midsize car without any tools? the answer is yes, by rocking the car and using the suspension as an oscilator it is possible to gradually increase the amplitude until it is possible to flip the car over. We don't have to go that far, but how about a jack that "steals" a little of each oscilation and gradually lifts the car. All you need to do is place the jack in it's position extend it to fill the gap and start rocking the car, the jack will keep expanding as long as you continue rocking.
 — gamb, Apr 14 2004

 Do you have any documentation of an unmodified mid-sized car getting flipped in this manner? I would think that the shock absorbers would damp the oscillations way too much.

 Now if the shock absorbers were removed first, they might have a chance, but it seems to me that stock springs would bottom out well before the car was rocking enough to flip. Redoing the springs and shocks sounds to me like cheating.

 As for your idea of making a jack as you describe, I'm not sure how you intend to implement it. It couldn't use the standard lift points on a car or when it ratcheted to prevent downward movement, you wouldn't be able to push the car down to get more bounce to make it higher. Or you could use the standard lift points if the jack had its own set of springs, but I thought part of the idea was to use the existing ones springs.

 If you rigged the jack directly to the tire (or to some part of the suspension), you would still have some difficulty, since you would need to get the car to bounce high enough to actually lift the wheel before it could ratchet up, or the jack would have to be pretensioned with some fraction of the car's weight, so it would start expanding when when a portion of the car's weight were off the tire (but again, that means adding springs to the jack).

 Was there some arrangement you had in mind that I'm missing?

Then there's the other question, assuming you did manage to get this to work: how is it any better than any other type of jack? The same amount of energy is required to lift the car, no matter how you do it, and the process of rocking the car will waste energy in the shock absorbers.
 — scad mientist, Apr 14 2004

Excellent! I voted for this for the visual, even though I doubt that it would work if you had a flat.
 — ldischler, Apr 15 2004

 [annotate]

back: main index