|
|
Post by nikeajax on Dec 16, 2017 8:56:23 GMT -8
Phil, BRAVO! Yes, you and I are the mad-scientists, but the intellectual rewards are what we find so gratifying and stimulating  JB |
|
|
|
Post by vance on Dec 16, 2017 9:21:58 GMT -8
As many of you already know, I also carry a second regulator. The problem I had with the Scuba regulator was never any real danger as I had the backup.
I was only trying to point out that this regulator has an unique potential for water leakage into the air side of the regulator, and it became more than potential on mine. My point is, to anyone re-building or repairing the Scuba, to underscore the need to check that the exhaust diaphragm is water tight.
As to thickness and folds, the membrane is not folded anywhere that is obvious. I'm not super confident butyl rubber is a good choice for the diaphragm in any case, as I have seen it degrade pretty badly in a tire over time. Silicone is probably a better choice, but it cuts easily. A cast silicone membrane, made to fit over the flange the way the originals did would be the thing. However, that isn't easy to accomplish. The Scuba is a work in progress!
BTW, no matter the implication of Crabby's statement above, you'd be very hard pressed to find a better dive buddy.
|
|
|
|
Post by vance on Dec 16, 2017 9:50:39 GMT -8
How about this as a test? I'm thinking of taking the cover off the regulator and taping off the exhaust holes in the top can. Duct tape should work. Then, rig up a container with a connection for the exhaust hose and raise it as high as possible above the regulator, filled with water. This should allow any leak in the exhaust diaphragm/flange interface to be discovered. No need to pressurize the reg.
|
|
|
|
Post by SeaRat on Dec 16, 2017 20:14:51 GMT -8
Phil,
I wouldn't raise it much more than a foot over the regulator. In reality, you're only talking about a few inches of water pressure. What I'm a bit worried about is that the diaphragm would be damaged if too much water pressure were to be applied from the opposite direction from its design.
John
|
|
|
|
Post by vance on Dec 17, 2017 10:05:29 GMT -8
Phil, I wouldn't raise it much more than a foot over the regulator. In reality, you're only talking about a few inches of water pressure. What I'm a bit worried about is that the diaphragm would be damaged if too much water pressure were to be applied from the opposite direction from its design. John No, not too high. I'd use the reg's own hose. BTW, that was another issue in diving the Scuba! The original hoses are very short, and not comfortable to use. They barely fit around you, and kind of jam the mouthpiece into your face! |
|
|
|
Post by SeaRat on Dec 17, 2017 13:05:34 GMT -8
Phil, I wouldn't raise it much more than a foot over the regulator. In reality, you're only talking about a few inches of water pressure. What I'm a bit worried about is that the diaphragm would be damaged if too much water pressure were to be applied from the opposite direction from its design. John No, not too high. I'd use the reg's own hose. BTW, that was another issue in diving the Scuba! The original hoses are very short, and not comfortable to use. They barely fit around you, and kind of jam the mouthpiece into your face! Phil, The actual original blue hoses with the Hope-Page mouthpiece on the original Healthways Scuba regulator were longer. It was their second and third generation hoses that were the short, black ones. John |
|
|
|
Post by vance on Dec 18, 2017 10:32:53 GMT -8
I did my pressure experiment on a newly RTV'd OEM exhaust diaphragm. It is a highly technical and expensive test, and not to be attempted by beginners! I clamped a hose on the exhaust horn, taped the exhaust holes close with duct tape, hung it all up on a special hanger, and filled the hose with water:    Here you can see the diaphragm and the tape over the exhaust holes bulging from the water pressure: 
 And here you can see no leak! The tape failed on the outside after a while, but the diaphragm never leaked a drop:
Now I'll attempt it with a rubber membrane. |
|
|
|
Post by nikeajax on Dec 18, 2017 11:58:14 GMT -8
Phil, I think you ought to try this with two hoses connected together: greater pressure will give you a better idea of what will happen at depth.
JB
|
|
|
|
Post by vance on Dec 18, 2017 17:29:33 GMT -8
According to John, as I understand it, no matter the depth, the ratio between the two sides is the same. The pressure differential between the two sides at 8 feet is the same as if it were at 30 feet. Pls correct me if I am off-base!
I think that if the duct tape sticky seal is broken by the water pressure over 20 minutes, but the diaphragm did not leak, then the seal on the diaphragm has proved itself. The diaphragm was very bulgy, and the tape too. There was a considerably higher amount of pressure on the exhaust side in this experiment than would be in use. I think? Again correct me if I am wrong, please. I'm here to learn!
|
|
|
|
Post by vance on May 6, 2020 15:40:44 GMT -8
A new tid-bit to add. I've made some stainless hose clamps kinda sorta reproduction-like, but with a bit of sophistication. They're wider, use 5-40 screws and nuts a bit longer than stock to alleviate pita problems. There's a slidey bit that goes under the band to keep it from pinche-ing (heh.) Made with the same stuff as the DivAir Diaphragm repro clamp. Thanks to Bill (Antique Diver) for the collaboration via e-mails.  |
|
|
|
Post by nikeajax on May 6, 2020 17:42:55 GMT -8
BWA-HAHAHAHA!  JB
|
|
|
|
Post by nikeajax on May 7, 2020 16:43:30 GMT -8
PY, is this a servicing date: or is that your scribbling? If that's a service, then way boss! JB |
|
|
|
Post by vance on May 7, 2020 16:59:29 GMT -8
Yes it's service date.
|
|
|
|
Post by nikeajax on May 13, 2020 16:23:06 GMT -8
Ummmmm-- YIKES!  OK, check out these new treasures for my HW-gear. First, an original diaphragm for the Scuba model-A: it's all rubber, no nylon:  JB PY, have you tried you OEM diaphragm? I let mine sit on the reg for, ummmmm, jeeeze, I d'know, but now if I use a pair of pliers to compress the ring-gap, I'm able to get it all to seat pretty danged well. I'm going through the process again for more compression. I also ordered some new extra long hoses for it too. I'm leaving the cans keyed, but will play with making a Snorkel-jet for it to make it an open-water reg John this is the Scuba I got from you JB |
|
|
|
Post by vance on May 13, 2020 17:25:36 GMT -8
Where are you getting extra long hoses? Are the the EPDM super stretch hoses?
|
|
OK, check out these new treasures for my HW-gear. 
