Transferring air from 1 tank to another

[duckbill]

That won't work.

But it will if he doesn't touch a thing inside the regulators, and just connects the HP ports together....

I'm not disputing the HP port idea. The point to which I was referring was his idea of gutting the regulators and connecting the LP ports. rcs9250 explained why that won't work.

 

[duckbill]

I'll spare you the math but just working it out roughly, if you fill a 1/2 full AL50 from a full AL80 then the pressure in the AL50 (in both tanks, actually) once they've equalized will be roughly 160 bar (or +/- 2300 psi).

This is a rough figure but it won't be too far off in practice.

Is this the kind of pressure you're looking for?

R..

Why do I get 1846 psi? Am I doing something wrong? (I am assuming the 80cf and 50cf cylinders are both 3000psi, and the 80 is full and the 50 is empty at the start)

3000psi x (80cf / 80cf + 50cf)
3000 x (80 / 130) = 1846psi

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Anyway, you'll end up with 49.23cf in the 80cf cylinder, and 30.77cf in the 50cf cylinder.

 

[redacted]

Problem had 50 starting at half full so 2400 is about the answer.

Why do I get 1846 psi? Am I doing something wrong? (I am assuming the 80cf and 50cf cylinders are both 3000psi, and the 80 is full and the 50 is empty at the start)

3000psi x (80cf / 80cf + 50cf)
3000 x (80 / 130) = 1846psi

----------------------------------------

Anyway, you'll end up with 49.23cf in the 80cf cylinder, and 30.77cf in the 50cf cylinder.

 

[garyd54220]

Jeez, are you too cheap to pay 6 or 8 bucks to fill your daughter's tank? What are you gonna do when she needs gear, make her a drysuit out of old innertubes? How about a douchebag BC (hopefully new)!

 

[duckbill]

Problem had 50 starting at half full so 2400 is about the answer.

Ah! Thanks! Not sure why the 50 would be half full or so to begin with though, unless he is talking about equalizing with two 80s.

 

[redacted]

Jeez, are you too cheap to pay 6 or 8 bucks to fill your daughter's tank? What are you gonna do when she needs gear, make her a drysuit out of old innertubes? How about a douchebag BC (hopefully new)!

Do you regularly throw away $6 or $8 when you don't have to??

Of course, it is OK if you do. But it is a little hard to understand why you think others should. Maybe he is trying to save those extra few dollars so she to can grow up and be a tech diver.

 

[garyd54220]

Wow, I really didn't think the humor was that subtle and even added the eyebrows to make sure people got it. I guess I better keep my day job! Please tell me somebody got it!!!

Gary

 

[redacted]

Wow, I really didn't think the humor was that subtle and even added the eyebrows to make sure people got it. I guess I better keep my day job! Please tell me somebody got it!!!

Gary

Perhaps I misunderstood. I clearly saw the humor in the douche bag wing (although I have made one from a pool float). But I took the comment about being to cheap to pay $6 or $8 for an (unnecessary) airfill as serious. Was I wrong?

 

[Web Monkey]

uh I'm sure there is a perfectly good reason why not but is it possible just to hook a high pressure hose up to 2 1st stages?

Because the HP fitting on most modern regulators has an opening that will just about pass a human hair and a trans-fill will take days.

Terry

 

[Web Monkey]

If the cost is a hundred bucks well I guess I'll just buy a 2nd 50 and be done with it. But if the cost is more like $25 then hey that makes sense.

What's your daughter going to do with ~30 CuFt of air in a 50CuFt tank?

Terry