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This is my idea for a Vacbed ice lock! It works with the expanding force of freezing water. Water has the feature to expand 8-10% when it freezes. I think it may be possible to use this feature, to squeeze a piece of silikone tubing, which is inside a metal pipe.
The vollume of a pipe with 50mm diameter and 80mm hight, wich is filled with Water, should be able to Squeeze a 12mm Diameter tubing.
Here is a drawing for better understanding.
The only problem that could happen, is that the Silicone-tubing is sticking together because of the pressure of the ice or maybe some leaking.
I will try to built a prototype in the next fiew weeks. Then i will see.
If this would work it sould be a realy good emergency release. What do you think.
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13 Jan 2017, 21:39
(This post was last modified: 13 Jan 2017, 21:43 by Like Ra.)
I'm not sure that this is what's going to happen. If you warm up a metal toroid, its internal diameter will increase, not decrease (if the circumferences of all "metal circles" inside the toroid increase, the diameters will increase too). So, if you freeze a hollow pipe, most likely, the outer plastic will expand.
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sorry Ra, but i think you are wrong. Water expands 8-10%, which is realy much more than any other material. Metal does the opposite. If it get´s could it shrinks. I am realy shure about that and I am an mechanical engineer.
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In any case I'm very interested in the results. Can "you try this at home"? ;P
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I have been thinking about this too. Except I was thinking of a T piece at the vac point.
Put a reducer in the right angle part of the T. In here you under another piece of pipe with a frozen core say 25mm Diam.
The straight through part has a small rubber ball and rubber o ring with a spring force that hold the ball sealed against the inlet of air.
Once sealed you the. Wait for the ice to melt and let air leak in.
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TADAAAA!!!!!
My prototype is ready! I put it in the freezer over night! I hope it works,
over wise i spent 20€ for nothing. Tomorrow we will see.
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Looks neat.
Why the T-piece pneumatic line coupling?
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(07 Feb 2017, 22:46 )ltxrob Wrote: Looks neat.
Why the T-piece pneumatic line coupling?
I have a Self built vacbed pump system with pressure sensor and a timer controlled magnetic valve for release. But i want to have a second (more save) release. This i why i built that Vacbed icelock.
I use the pneumatic connectors on my Pump and on my Vacbed. That way, it is easy to install the Vacbed icelock between the Vacbed and the Pump.
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I cant imagine how its working in practice ... you wrote you install it between vacbed and pump ... but if you freeze this lock, how you can get air through it?
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Yeah, to be honest, me neither 😉