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Post by vance on May 2, 2017 16:19:32 GMT -8
The diameter of the threaded part of the valve body appears to be the same as the USD body. However, there's a step machined into the HW body that makes the diameter about 1/16" too big to fit in the USD can. The threads for the gland nut appear to be the same. I have NOT actually checked this!!
I will, but later, aight? These speculations are guesses. I don't think the gland nuts are identical, either.
But, after enlarging the hole in the Mistral top can, the valve body fits nicely, and the levers are easily within the adjustment range to work perfectly. This should e a functional unit.
I can't imagine why this mod would be necessary, unless someone had a crappy old Mistral can with no guts, but a diaphragm and maybe a duckbill, plus an HW valve body and levers going begging and wanted to get them together! I think it should be a nice combination, actually. I can't wait to try it.
Hope Page hose loop? That'd be sick....
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Post by vance on May 2, 2017 17:08:56 GMT -8
DD asks about the relative sizes of the HW and USD cans. Nope, different. The HW is bigger and the sealing surfaces are different. It seems the Gold Label went toward the USD flanges (a good idea, btw) rather than the flat, held together by compression and the ring, HW used for so long.
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Post by vance on May 2, 2017 21:10:41 GMT -8
Earlier in this thread (couple of days back) I reported that one of my Scubas breathed a bit harder in than the other. I just remembered that I filed the flat out of one of them and turned the valve so the channel of the lever assembly pointed at the intake horn. John pointed out that I had only succeeded in directing the air away from the horn, not toward it.
Foolishly, I didn't make a note of which Scuba was which. I wonder if that is the reason why it didn't breathe as well? OR maybe it's why it breathed better! Unlikely. the engineers at Healthways knew what they were about.
When I take them apart to do some lever tweaking, I'll sort out which one has the innertube or the swimcap, and which one has the valve body turned cattawampus. I'll also compare the adjustment heights of the levers to see if I can figure out why one is better than the other.
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Post by SeaRat on May 3, 2017 14:15:27 GMT -8
Earlier in this thread (couple of days back) I reported that one of my Scubas breathed a bit harder in than the other. I just remembered that I filed the flat out of one of them and turned the valve so the channel of the lever assembly pointed at the intake horn. John pointed out that I had only succeeded in directing the air away from the horn, not toward it. Foolishly, I didn't make a note of which Scuba was which. I wonder if that is the reason why it didn't breathe as well? OR maybe it's why it breathed better! Unlikely. the engineers at Healthways knew what they were about. When I take them apart to do some lever tweaking, I'll sort out which one has the innertube or the swimcap, and which one has the valve body turned cattawampus. I'll also compare the adjustment heights of the levers to see if I can figure out why one is better than the other. I cannot say whether this was your problem with one that did not breathe well, but usually it is either the levers' setting, or the orientation, or the non-return valves that affect this. I set the levers as high as I can without any leakage when the diaphragm is clamped in place. If the orientation is not toward the intake horn, it will cause turbulence which will cause harder breathing. If the non-return valve is stuck, even slightly, that will also affect breathing resistance. Now, about the Healthways engineers, you need to understand that divers in the 1950s sometimes did not value easy breathing regulators; they felt that these regulators made them use air faster. This was disproven over about ten years, but that was part of the thinking early on. Engineers were more into simply getting the regulators to work than ease of breathing in the early days too. The competition was the DA Aqualung, a notoriously hard-breathing regulator (but very, very quiet). I selected the Healthways original SCUBA over the USD Mistral as my first regulator because of the smooth breathing, and it was quieter. But I was a teen at that time too, and on the swim team. John
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Post by nikeajax on May 3, 2017 14:59:59 GMT -8
The competition was the DA Aqualung, a notoriously hard-breathing regulator (but very, very quiet). John John, is it the early DA you are referring to? I don't own one and never will, but I have never heard anything bad about them, unless this the model that Dick Anderson had to perpetually-retune when he worked for Rene? JB
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Post by SeaRat on May 3, 2017 16:56:44 GMT -8
The competition was the DA Aqualung, a notoriously hard-breathing regulator (but very, very quiet). John John, is it the early DA you are referring to? I don't own one and never will, but I have never heard anything bad about them, unless this the model that Dick Anderson had to perpetually-retune when he worked for Rene? JB Jaybird, Yes, the DA Aqualung, also known as the Broxton Aqualung regulator, is the first production regulator of U.S. Divers Company. When I first got it, it was serviced by Bill Herder of Deep Sea Bill's in Newport, Oregon. It breathed so hard that I decided it was a pool-only regulator. I think I measured it at somewhere between 6 and 8 inches of water pressure on the inhalation. After years of non-use, I sent it to Broxton Chuck, and he tuned it to its best performance, and now it breathes between 2-4 inches (probably) of water pressure on the inhalation. Exhalation through the old-style screw-in duckbill is actually very, very nice. It is a very silent regulator, and sounds exactly like the regulators that Cousteau and his team used while filming The Silent World (because it is the same regulator). If I can get PhotoBucket up and running, I'll give you some photos of it. But this was the competition for the Healthways SCUBA regulator at that time. John This is a U.S. Navy photo from way back, showing one of the first Aqualungs that the U.S. Navy had used. This is my Broxton, with the "Professional Mouthpiece" on it and DX Overpressure Breathing hoses (which are indestructible). Here is this DA Aqualung regulator on my twin 52 tanks. I took this off a video, and wanted to show how the regulator looked in a doff and don exercise. Here I've done an open water doff and don exercise with this DA Aqualung regulator, and this view shows the particulars of the regulator on the tank. I do now use this regulator in open water, and took it in both the Clackamas River (above) and in Big Cliff Reservoir at about thirty feet depth with Sid Macken as my buddy. I was using it with a Hope-Page mouthpiece for that dive. Many do not know that U.S. Divers sold for a little while the Hope-Page mouthpiece as an upgrade to its own solid hose-mouthpiece system for their original DA Aqualung regulators. It is in the book " Dive, the Complete Book of Skin Diving."
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Post by nikeajax on May 3, 2017 17:46:20 GMT -8
EXCELLENT--thanks John! I find this perplexing in that; how could factory specs be so FUBAR? If you'll remember, in that article John68 gave us, it was saying that until competent mechanics like Diver Dick got their hands on the Broxtons, they had the ability to be quite literally, deadly!
JB
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Post by SeaRat on May 3, 2017 18:15:36 GMT -8
Here was one of the early apparatus for looking at work of breathing by Dr. Glen Egstrom, probably late 1960s. This is yours truly with the DAAqualung regulator prior to my dive in Big Cliff Reservoir several years ago. These photos are of my DA Aqualung, Broxton regulator. John
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Post by vance on May 5, 2017 9:47:52 GMT -8
I put the Misuba rev1 on the tank. It leaked at the lever height I usually put them on a HW can. I lowered them and again got a leak. Lowered them again, and still leaking slightly. Lowered again, and no leak. However, kind of hard breathing.
I think the can height/diaphragm dome won't allow the levers to open the valve enough to get easy breathing on it. The only things I can think of to get more valve movement would be: 1. Bend the lever ends down, allowing the lever to be raised higher; 2. Back the valve down farther into the can by machining the valve body to get more distance between the levers and the diaphragm; 3. Shimming the diaphragm up and away from the levers.
The second and third ideas are impractical since I don't want to make any permanent changes to the valve body, and shimming the diaphragm would require an alternative clamping setup. The first idea, bending the levers, does not appeal either. I'd hate to make such a mod on a good set of levers.
I tried a new silicone diaphragm with some improvement. Not great though. Even though it's ALMOST there, I'm going to call a relative FAIL on this. I might try the Gold Label valve, but, then again...what for? If I run into a set of levers I don't mind bending, I'll try again.
EDIT: I have spent the morning adjusting levers on Scubas. I went back to the Misuba r1 and did some tweaking. It is now breathing as well as the Scubas. I take back the FAIL and claim success! And, it's much quieter than the Mistral.
Pool test!
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Post by vance on May 5, 2017 14:40:01 GMT -8
Here are pics of the Misuba r1 almost ready for the water. I just need to get some hose clamps. I should call it the Stealth Misuba r1! It's much quieter than the Mistral on the inhale. I'm using a fartbill on it now, but will get a DBE next time I order stuff from VDH. That might quiet it even further. Speaking of duckbills, I made 3 more silicone duckbills for the Scuba regs. These are a bit more sophisticated, and are thinner with better wall thickness regularity. I glued one in a Scuba with RTV and tried it out. Works great on the bench. I used my custom duckbills in the two Scubas I tested in the pool, and the breathe fine. This one should be slightly better as it is more flexible. I doubt anyone could tell the difference, however. Speaking of RTV, I tried a cut down USD type duckbill on the exhaust horn of one of my Scubas, and glued the fold-over on to the outside of the horn to keep it in place. Two things: First: The edges on the Scuba stamped sheet metal horns are sharp. They cut the duckbill, which would have allowed air to get past the seal. If a fold over is to be used, some means of protecting the duckbill would need to be used. Second, a thin layer of RTV was left on the horn after I removed the duckbill. The thin layer is extremely tough and hard to remove. It got me thinking that a smear of rtv on spots of bare brass where chrome was lost would protect it from corrosion like nobody's bidness. You could coat the inside of a regulator can that has major chrome loss, and Bob's your Uncle! I just happen to have a Scuba top can that's pretty bad inside. I think I'll try this. Off-gassing might be a problem, but if you coated the inside and let it dry for a few weeks....?
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Post by vance on May 6, 2017 15:41:58 GMT -8
Speaking of exhaust valves, check out this Russian duckbill! It looks kina obscene....or maybe a piece of a squid. Not sayin' what piece!
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