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Stone Shifting 2

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Steve Gray S
Steve Gray Aug 30, 2003 16:05:33
Replying to nigelswift

ROTFLOL - I just loved your Gandalf imagery.

I think I'll see how the model behaves if we consider the tower to be free to move, i.e. it will not resist any side load. If it works, we just don't worry about bracing the tower, we let the logs slide over the ones below and the tower will end up looking something like Gordon's stack of pallets. Not quite the pile of rubbish you envisioned, I'm afraid.

For those unfamiliar with newsgroup/chat room shorthand ROTFLOL is "rolling on the floor laughing out loud".

G GordonP
GordonP Aug 30, 2003 18:02:59
Replying to Steve Gray

I'm still thinking about the reason for the slopeing side, the ancients never did anything without a reason.

We now seem to be assuming the cutaway was to allow the bottom of the stone to clear the far edge of the hole as it rotated from a low launching tower. this could just as easily apply to a low launch from the other side if the setup was designed for the stone to begin its entry into the hole at less than vertical.

Without computors perhaps they didn't have the confidence to launch the stone towards a slopeing side but relied on the vertical side to deal with the extra momentum they had purposely built in to the system.

S Steve Gray
Steve Gray Aug 31, 2003 11:18:51
Replying to Steve Gray

OK, I modified the model to allow the tower to give way in a horizontal direction. It doesn 't work very well unless there is a reasonably amount of friction involved. In any case the tower needs to be higher so that the smaller amount of rotational momentum it can induce in the block will still be able to rotate it to vertical in the time it takes to drop.

To summarise or findings so far any of these would work:

1. A tower that can withstand a 10 ton side load and a normal amount of friction.
2. A tower that can withstand a 20 ton side load and a nice slippery track for the block.
3. A tall tower that can deform horizontally under load, but offers a fair amount of friction in doing so.