Gina's flight to reality - don't try this at home, or anywhere else. Especially if you do it as described. Because if you do you won't be coming down anytime soon, unless someone else lets you down.

You see Gina took great pains at getting all the weights calculated except she forgot one very important item. THE ROPE!! I go climbing and repelling and I can tell you first hand that rope does indeed have weight. Now I have not sat down and figured out how much it weighs, but I use 1/2" rope. And I would guess it comes in at about 1 lb per 10 feet.

Gina is using 225 feet of rope. And of that only 10 feet, according to the story is going from her wrist bar to the pulley on the rod. That means the other 215 feet are all on the same side as the barrel. So the weight of that rope must be added into the weight of the barrel. That is another 21.5 pounds. You might also notice that the difference between the barrels weight and hers is actually 19 pounds 8 ounces.

With the weight of the frozen water being 20 pounds she was depending on the extra 8 ounces, if 20 pounds 8 ounces was correct, to eventually allow her to reach the bottom and free herself. Unfortunately there is an additional 21 1/2 pounds of rope that she did not account for. This means there is no way that she would ever come down. The total weight of the barrel and the rope is 136 pounds, she weighs only 115 pounds plus maybe one pound for the rope on her side of the pulley and another three pounds for the rest of her restrains, that is a total of around 120 pounds. Oops!!!!!!!

I wrote this for two reasons. The first is that when you see a story like this and it gets you so excited that you want to do something based on this idea that you remember to take into account every detail. Because if you don't you have a major problem.

The second reason is to alert anyone who might decide to try this despite the warning and really make a big mistake. Self bondage can be rather unforgiving. Especially if you make a mistake.

Be careful and have a great bondage.

By the way I wouldn't mind meeting a F for bondage times and pics.

Call me Alley Oops a practicing self bonder.


Some more comments on the physics in the (artistically pleasing) Gina story;

- Alley's right, although if Gina was smart, she'd have used a continous loop of rope, so that it always balanced itself.

- While the ice was melting, but still heavier than her, she would have gone nowhere. As soon as it became lighter than her, she would have accelerated downwards at 9.8ms^2, modulo the effects of frictive resistance against the (initially small) downwards force. (But note that static friction is greater than dynamic friction, so once she started she'd never slow down.)

In plain english; once the ice got lighter than she was, she would have plummeted like a rock to a messy ending.

Now, what she _could_ have done was use a variable-friction cable brake. But perhaps a little less in the "tradition" of using ice for self-bondage 8)

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