Test dove 4 DH regs today, 3 for the first time.

[elmer fudd]

The good news is they all worked. Two worked perfectly. One worked surprisingly well and one still needs some work. The dives were all brief with the longest lasting about 8 minutes and a maximum depth of 30'. I also had one of those infamous Spare Airs necklaced under my chin just in case.

The first was a Healthways Scuba, (blue label), with a Hope Page mouthpiece. When I got it, it was free flowing, but after changing the o-rings and resurfacing the seat and orifice I got it sealing pretty well. I wasn't particularly happy diving with it though. The main problem was with exhalation. I had an incident once where I lost the duckbill in my RAM. You literally had to force the water out of the hose to exhale. This wasn't as bad as that, but I'm pretty sure water was getting in there and making things difficult. Also, I think the crackly old diaphragm and lack of venturi action handicap it.

The second was a Northill Airlung. I bought this one about 6 months ago, avidly tried to rebuild it for about a month, then lost interest and set it aside. A couple weeks ago, I decided to work on it some more. I ordered a NOS seat and did some more diaphragm work. This time it seemed that I did get it breathing. Today I tested it out, and damn...it worked pretty darn well. It's a noisy breather, but that exhaust valve integrated into the diaphragm means exhaling is practically effortless. Inhalation is pretty easy too though. It may not be a RAM, but it ain't bad at all. After diving the Healthways it seemed like heaven. Now there still are some issues with it that make me hesitant to use it on a regular basis. That diaphragm exhaust valve means that some water gets into the action. Not enough to interfere with breathing, but enough to make you want to disassemble it entirely and soak it after using it. Second, because of the yoke on it, it should have a post valve on the tank with no J-valve. If you don't have a valve like that, you have to mount it upside down and somewhat high. Third, I still need to sort out the mouthpiece. It was leaking the last time I used it, so this time I swiped the hoses off my RAM. Fourth, it sometimes wanted to honk at me a little if I was tilted down and inhaled hard. Still, I was very pleased with how well it worked.

Third was a square label RAM I picked up in a package deal a week ago along with the HW and a DAAM. The duckbill was bad and so were the hoses and mouthpiece diaphragms, but other than that it breathed great. It dove great too.

And so did the DAAM. With about 1000 psi left in the LP72 I'd been using, I couldn't really tell a lot of difference from the RAM. I think the inhalation was maybe a tiny bit harder, but not that much.

Finished everything up with an hour long dive with a Mk5/R109 and I swear that thing breathes as good as my Mk25/G250V.

 

[Eric Sedletzky]

Very cool.
Thanks for the great report.

I have a Healthways "Scuba" double hose that a good friend gave me as a gift to get me into the double hose world.
The only thing that makes me nervous about that regulator is the way the exhaust valve has that membrane that is placed between the exhaust chamber and the fresh air chamber. If that membrane was to rip or fail it would mean sucking straight water with the next breath, yikes!!
I am too nervous to take it deep.

 

[elmer fudd]

I think that's where my HW is failing too, that funky exhaust arrangement. Even if it does fail though, it doesn't mean you just start sucking water. You should have an exhaust diaphragm in the mouthpiece too, so what happens if the membrane fails is that exhaling just becomes really difficult. You can still breathe though.

 

[herman]

That funky arrangement on the early HW regs is a pita. The later models that use just a single mushroom valve in the outer can work quite well. I did a good many dives in April using a later model (post 62 with the venturi) HW SCUBA on Bonaire, several to over 100 ft. It is fitted with a reproduction diaphragm, modern mushroom valve and a USD curved mouthpiece with upgraded wagonwheel valves. This thing is great and became the favorite reg we had with us - 3 vintage divers. One odd thing about the HW design we noticed is it works very well with high pressure tanks. The dive op was being generous that week, some tanks were in the 3500 psi range and unlike Mistrals who really dislike high pressure, the HWs worked better at the high end of the tank.

 

[simonbeans]

The Healthways series will soon be upgradeable with a new diaphragm. Check these threads at VDH for the discussion.

Vintage Double Hose • View topic - Reproduction Healthways SCUBA Silicone Diaphragm
Vintage Double Hose • View topic - Healthways Update

 

[Eric Sedletzky]

I wonder if there's a way to close off that opening between the exhaust and fresh air sides and do something else with the exhaust valve?
I suppose it would mean tig welding a plate over that opening (I think the bodies on those are stainless) and figure out a way to incorporate something like a duckbill eliminator inside the end of the exhaust cavity by the exhaust holes?

 

[elmer fudd]

I think there must be some way to improve it. To some extent though, I wonder if I really should, or should I just restore it to as close to it's original state as possible. I'm leaning towards getting it working and keeping it as stock as is practical, while still retaining it's function as a safe working regulator. When the new diaphragms come out I'll definitely get one, because diving with a crackly 50 year old diaphragm for the sake of being period correct is just dumb, but other than that, I think I'll keep it historically correct.

Creed over on VDH has some awesome threads if you were to go the other route. He set up one of the blue label Scubas with a balanced valve and made an adapter plate to create a venturi action.

 

[Eric Sedletzky]

I think there must be some way to improve it. To some extent though, I wonder if I really should, or should I just restore it to as close to it's original state as possible. I'm leaning towards getting it working and keeping it as stock as is practical, while still retaining it's function as a safe working regulator. When the new diaphragms come out I'll definitely get one, because diving with a crackly 50 year old diaphragm for the sake of being period correct is just dumb, but other than that, I think I'll keep it historically correct.

Creed over on VDH has some awesome threads if you were to go the other route. He set up one of the blue label Scubas with a balanced valve and made an adapter plate to create a venturi action.

I was talking about me doing that on my Healthways Scuba DH reg.
l'll have to check out that article on VDH you speak of.

I would be fine with a new reproduction exhaust flat membrane (or whatever you call it) - you know what I'm talking about. The old one is original and as such is hardened and no longer very flexible, but it still works somewhat and isn't perforated. It makes exhaling a chore though and that's that last thing you want when trying to have a relaxing dive.
Along with repro diaphrams maybe repro exhaust membranes would be in order also since those should be changed every few years for safety anyway.

 

[elmer fudd]

I had really good luck making the diaphragm for my Northill out of a sheet of silicone rubber. Makes me wonder if I couldn't make use of some of the leftovers to fix the exhaust seal.

 

[Eric Sedletzky]

I had really good luck making the diaphragm for my Northill out of a sheet of silicone rubber. Makes me wonder if I couldn't make use of some of the leftovers to fix the exhaust seal.

I thought of doing the same thing. Silicone would be the ultimate material for that; flexible and strong.
My problem is I'm at a loss as to where to start with finding the material to make a membrane and I'm not so sure it was the greatest design to start with.
That's why I thought of bypassing the entire membrane idea and going with a sealed fresh air chamber and doing something else with the exhaust system. I know that the patent laws imposed by Aqualung with the duckbill prevented Healthways from having a split can and duckbill style exhaust system so that was their idea on how to get around it and still have a sealing exhaust valve, but it sucks.
Since the regs are long gone and so is the company it doesn't matter any more what we do. I don't really care about preserving historical accuracy with absolute stock cofigurations, if I can modify something so I can dive it and nobody knows the difference by looking at it, what the hell?