Steve Gray
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Re: Do we need ropes?
Sep 16, 2003, 18:09
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Hey, I think I've just had a brainwave.
Suppose we made a long rectangular frame of logs that can be dug into the ground so that it will lean against the back of the 70deg stone near the top like a shore. Levers attached to the top edge of the frame would make contact with the stone and would stick up above it. Ropes from the levers would then be pulled causing the stone to be raised a little. Packing would be rammed into the hole behind the stone and then the rope pullers would relax. When they did, the frame would drop a little to take up the new position of the stone and the process can be repeated.
The redcution in mechanical advantage caused by the frame moving lower on the stone will be compensated for by the fact that the leverage required to raise the stone becomes less as the stone gets more upright.
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GordonP
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Re: Do we need ropes?
Sep 16, 2003, 18:12
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Still thinking of levering at 90 degrees to the braceing strutts, (surely that must half the pressure) also trying the bracing strutts again at an angle of 90 degrees to the lintel placed at the other side of the upright. No need to take the ropes under the upright, just under the lintel.
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GordonP
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Re: Do we need ropes?
Sep 16, 2003, 18:16
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Your latest brainwave just beat my latest posting to press, let's keep thinking.
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GordonP
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Re: Do we need ropes?
Sep 16, 2003, 18:16
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Your latest brainwave just beat my latest posting to press, let's keep thinking.
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GordonP
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Re: Do we need ropes?
Sep 16, 2003, 18:24
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Just a thought Steve, whether we lever off the platform or a brace we still need the platform to stand on.
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Steve Gray
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Re: Do we need ropes?
Sep 16, 2003, 19:36
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Yes, the principle of levering at about 90 degrees to a bracing strut is correct. Any more or less and you start to have to rely on frictional forces to hold it all together and they can be fickle.
My thought with the "brainwave" brace was that the brace and its levers would be partly erected, then the tower would be removed and work on the brace would be completed. The levers automatically reset after each "relax" phase, so you no longer need access to the top of the tower (the levers are operated by ropes).
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GordonP
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Re: Do we need ropes?
Sep 16, 2003, 19:44
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Levers won't hold themselves upright, each lever needs a man. Why not make the tower also the brace, that way men can stand on top of the tower and control the levers.
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Steve Gray
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Re: Do we need ropes?
Sep 16, 2003, 22:29
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Hmm.. I was trying to avoid having to build the tower up to 24 feet when it only needs to be about 14 feet to get the stone to 70 degrees.
I wonder whether somehow we could lever the props from ground level.
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GordonP
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Re: Do we need ropes?
Sep 17, 2003, 04:55
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Another 10ft with the stone out of the way is no problem. We can use the weight of the lintel to stabilise the tower. I can see no practical way of operating the levers without men on the tower to control them, even at an angle of 45 degrees to ground level the levers will have a mind of their own otherwise.
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nigelswift
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Re: Hole Profiles
Sep 17, 2003, 07:59
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Steve, on the subject of your question, how did they get the trilithon stones through the sarsen circle, it seems that the sarsen circle did indeed pre-date the trilithons by a long time and with some degree of certainty.
However, I came across this statement:
"Of the 30 standing Sarsens, only one is of an uncertain date".
That'll be it then, I'd imagine.
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