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Comment by PhantomGremlin | Hacker News Reader

The video posted above shows this more clearly, all four wheels

The video shows nothing. It only shows "before" and "after", not "during". It's totally fake. The video doesn't answer the question of how the wheels magically get on top of the sled.

Is the body somehow jacked up to lift the car off the ground? If so, how is this done safely? Most unibody cars can only be jacked up by lifting at very specific points. You can't just slide a large piece of metal underneath to lift the car. Well, you can, but you'll probably damage the car.

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It seems pretty clear. The fingers on the sled go underneath the wheels of the car.

Watch 1:12 in the video. You can see the white-tipped prongs around the wheel

Here's a side view.

   _O_    _O_

Come on, guys. It's emphatically NOT CLEAR.

There's a jump between 1:11 and 1:12 in the video. Just before, the sled bumps into the tires in the front of the car. You can actually see the car physically jerk back as the sled hits. Just after, all four wheels of the car have magically appeared on top of the sled.

Phooey.

If this were as simple as everyone thinks, there would not be a jump in the video at the exact point that the magic happens!

You keep saying "on top of the sled".

The sled moves under the car. When the sled is under the car the fingers extend under the wheels. They do not, cannot, extend under the part of the wheel that is in contact with the ground. But they can, and do, extend to the parts of the wheel that are close to the ground. Again, look at 1:12. You can see the prongs go around the wheel, not directly underneath it.

You can see the prongs go around the wheel, not directly underneath it.

The videos linked to by improbable22 make it easier to see this.

My (very limited) understanding of radial tires (or at least steel belted ones) is that it would be bad to stress the tires in that manner for long periods of time. But lifting the car by the tires this way for a few minutes should be OK?

It would be interesting to learn what tire manufacturers feel about this. (Of course they probably would want to disclaim liability because there's no reason for them to want to bless this).

30s: https://www.youtube.com/watch?v=bocfNOjeBm8

40s: https://www.youtube.com/watch?v=zIaxPa2aUDI

Thank you. Those videos illustrate the concept much better than any others.

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