Device to expand rubber tubing

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SSCBen
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Device to expand rubber tubing

Post by SSCBen » Wed Jul 26, 2006 6:06 pm

A problem with current rubber CPS systems is that stacking rubber over rubber is difficult. I have designed a device to remedy this problem.

After noting that the power of my new pressure chamber was slightly lower than the original without additional layers (given ~2 - 3 feet less of range), I do believe that the amount of clearance is important. Indeed, with less clearance the inner tube receives less contact when it contracts to smaller than the larger tube's diameter. So, having a tube to layer over another tube that has the same or a similar diameter is ideal.

This device I speak of will essentially be like the shoe-stretchers except different. It will use 4 metal rods pulled slowly outward by a rope and hand-crank system (for torque) to expand the tubing. The ropes from the metal rods obviously will be attached to some sort of structure. I'm still working on the locking mechanism in my head. A device like this to expand the tubing should make applying additional layers easy! Just load the tubing into the device, turn the crank until it is wide enough, lock it, and then insert the smaller tube to be layered over.

If someone couldn't make a good drawing of what I am detailing, I'll make a notebook paper drawing. ;)

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Silence
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Post by Silence » Wed Jul 26, 2006 7:39 pm

Sounds good, but with all that force, perhaps there should be something on the other end of the tub to make sure the four rods don't come together on that side. It would be hard to do, but it might be more practical than an incredibly strong device.

EDIT: I suppose the edges of the rods on the opposite side of the expander from the rubber can be connected, allowing for a "conical" expansion. It wouldn't be even, but maybe the larger mouth would actually make accessing the inside of the easier.

You could use four strings that go through the outer inner (no pun intended :p ) tube or LRT and pull out on both sides of each string. Also, a pulley system would make pulling equally on all the string ends a bit easier. However, no matter what method you use and unless you've found a workaround, it will be just as hard getting the rods or string out as pushing in the smaller tube the traditional way would be. Perhaps it would be easier to collapse the inner inner (no pun intended this time, either :p ) and make it easier to slide more tubing on top of...

And remember, as somebody said in the Colossus thread, you can coat the tubing with talcum powder or something else to make it smoother. It does sound like it would work wonders...
Last edited by Silence on Wed Jul 26, 2006 8:14 pm, edited 1 time in total.

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SSCBen
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Post by SSCBen » Wed Jul 26, 2006 9:34 pm

I don't think you understand how I will make this. The tubing expands like a square getting larger, evenly on both ends of the tube. The pipe remains parallel. Easy to do and would work perfectly. The only trouble is finding small and strong pipe.

A picture probably was necessary, but I think I'll let the finished product be the picture.

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joannaardway
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Post by joannaardway » Thu Jul 27, 2006 5:15 pm

Sounds a bit complex to me, but after you've done it, I imagine you could sell layered LRT like spudtech does rifled PVC.

I have no objection to this idea.
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