CPH Rubber Tubing

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WaeV
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Joined: Sun Mar 29, 2009 4:01 am

CPH Rubber Tubing

Post by WaeV » Tue Apr 07, 2009 12:14 am

I was reading killer7's method of layering tubing to achieve higher pressures and wondered why not just use a higher rated piece of tube? There are tubes on McMaster-Carr with an ID of 1/8", OD of 3/4" and a psi rating of 85 for only $3.35! What's the advantage of layering when one can buy it like this?
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Silence
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Re: CPH Rubber Tubing

Post by Silence » Tue Apr 07, 2009 12:52 am

Sometimes you may still need to layer LRT on top, perhaps just with bicycle inner tubes. Or maybe you don't even have access to LRT at all.

Here the problem is with the inner diameter of the tube. 1/8" will really constrict the flow, and the hose barb itself has to be even narrower than that.

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WaeV
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Re: CPH Rubber Tubing

Post by WaeV » Tue Apr 07, 2009 12:55 am

Ok, but what about 3/8" ID, 3/4 OD, 35 PSI? How high should the PSI be?
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SSCBen
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Re: CPH Rubber Tubing

Post by SSCBen » Tue Apr 07, 2009 2:28 am

WaeV,

The pressure should be as high as you want it. You have to figure out what pressure, inner diameter, and nozzle diameters work for you and plan around that. The 35 psi tube you've mentioned is about as powerful as the bladder in the CPS 1000/1200/2100 class of water guns.

One thing to keep in mind is that the reported pressures are not the actual operating pressure of the tube. I remember doing some measurements earlier with one tube and the operating pressure was about 2/3 the reported pressure.

Also, while the smaller diameter tubes will have higher pressure, their capacity is significantly reduced due to their small diameter and their flow will be very restricted for the same reason.

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