Diving Two Hose Regulators: Questions

[oxyhacker]

There's some guy who sells (sold?) a 2-hose service manual on Ebay from time to time. It's just a cut-and-paste of the old manufacturers literature, but quite comprehesive, and he's added some useful info, like on how to make tool to remove the clips on the Spiro/USDs.

The ultimate resource is a copy of Fred Roberts BASIC SCUBA. This is a hardbound book, printed in the '60s by D. Van Nostrand and fairly rare now. It contains schematics and discussion of all the regs on the market at that time. It was, I think, the only all-make reg technical book ever published until ours came along.

The odd thing about Roberts book is that while it has schematics for dozens of regs and much info about the different models and variants, it has almost no service info on actually servicing or tuning them.

USD used to give out a service booklet, called AQUA LUNG DIVING, so owners could service their regs. Don't know if anyone has reprinted it, but it would be worth having too.

 

[Wildstar1063]

Rag,

Thanks for the links, I've had vintage Scuba
Supply, and VIntage Scuba in my bookmarks
for a while now, but the goingunder.net link
I'v never seen befor, that seem to be an
excellent source for parts.

Like I said though, these sites talk about the
hardware, but NOT about diving with it.

I have been Compiling the answers I've gotten
here and fron the two other threads you
mentioned, in to a F.A.Q.
------------------------------------------------------

Oxyhacker,

Thanks for the books recomendations, I found
the "Basic Scuba" book for sale at Vintage Scuba supply, for $80.00. I'm hoping to get it on ebay a bit cheaper. I could not find the
"Aqua lung Diving" booklet though.
------------------------------------------------------
Any one know of any text or .pdf files
dealing with 2 hose repair and set up?

Or any other texts dealing with diving
these old regs

I'm suprised, that since Nemrod made the SNARK III up untill 99, or so there are not
still people diving those regs, and more parts
availability.

Wildstar1063 (AKA Chuck E.)

 

[oxyhacker]

My understanding was that they didn't exactly keep it in production until then, but rather, ran off a batch or two in the late 90's most of which probably went straight into the hands of collectors.

I dove with a guy who was using one. Seemed to breath quite nicely. But then I was diving with an early Dacor two hose that I'd bought at a yard sale on the way to the dive, so this may have altered my perceptions.

Wildstar1063 once bubbled...
I'm suprised, that since Nemrod made the SNARK III up untill 99, or so there are not
still people diving those regs, and more parts
availability.

 

[neil]

rag once bubbled...

Really? How about the (not 'Royal') Aquamaster? Isn't that an upstream design? And if so, is the second valve designed to withstand the pressure if the first stage leaks?
In the Nemrod's Snark III there's an overpressure relief valve in the IP-chamber. (and then they called it "a 3-stage regulator"...)

It looks to me as if both the Royal and the not-Royal have upstream 1st stages. However, the second stage on both is downstream and that's where it matters. The downstream design is made to relieve over-pressure in the LP chamber (and the hose, of course). So the answer is that the 2nd is not designed to "withstand" 1st stage leaks, but to open when the pressure gets too high. Near as I can make out from the diagram, the Snark is also an upstream 1st, downstream 2nd, and the safety is just an ordinary looking overpressure valve in its own port.

I have manuals for the following DH regs:
Aquamaster
Royal Aquamaster
Mistral
Snark III Silver Deluxe
Some Voit and Dacor

I just entered the 21st century and bought a scanner so I'll try and make pdf. files if anyone wants them. Or I can just copy them and mail 'em. PM me with requests

 

[oxyhacker]

The 2nd is upstream too - otherwise there'd be no need for the "3rd stage".

The 2nd stage valve mechanism, with the upstream valve and compound levers, is just about identical in concept to the ones used on the single stage double hosers. The Aquamasters, on the other hand, uses a downstream poppet on the 2nd just about identical to the ones used on single hose basic downstream 2nds.

Now for a bit of trivia: under what label were the Nemrods orginally sold in the USA?

(btw this thread has got me kicking myself for not buying one of the new Snarks a few years ago when they were available)

neil once bubbled...
Near as I can make out from the diagram, the Snark is also an upstream 1st, downstream 2nd, and the safety is just an ordinary looking overpressure valve in its own port.

 

[neil]

Vance,
I'm sure you're correct, of course, I just looked a little more carefully at the diagram. Little, itty-bitty pictures of itty-bitty parts, and it's difficult to see what side of the poppet has the seal.

Nemrod was marketed by the Seamless Co. in New Haven, CT, a division of Dart Industries, Inc.
What do I win? How about a copy of one of your books?

Neil

 

[Bob3]

I have an "ongoing project" of scanning every older parts & service manual I can find into PDF format.
I still have about 11 lbs of manuals to scan in, had to take a break for a while.
Started hearing the bzzzz... beep... bzzzz... in my sleep after the first thousand or 2 pages. :bonk:

I used the Snark III into the mid 70's till I got my hands on some Cyklons. The antifreeze protection on the Cyklons being the selling point. The Snark breathed about as easy as any reg 'till then but the Cyklon would let you draw a vacuum on your tank when the handle got unintentionally whacked into the down position.
I was happy to get a SPG shortly after.

For ice diving I'd still use the Snark with the Cyklon on a 20 cf bailout bottle (former O2 bottle)

 

[Wildstar1063]

Bob3, and Neil,

What surprises me is that there are not already
scanned PDF of these old manuals on the web.

People are Constantly selling photocopies (Some
that I've seen look like photocopies of
photocopies) of these on ebay, and I'd think
some historical diving Organization would have
these available for download.

If any one has a PDF of the manual for my
Royal (Round sticker not square metal tag)
I'd would very much appreciate a copy.

Thanks

Wildstar1063 (AKA Chuck E.)

 

[neil]

All my manuals are originals so they should scan okay as pdf's once I figure it out. If they don't scan well I'll just copy them for you.
Neil

 

[neil]

Hey Bob,
How about a quick tutorial on scanning manuals. I just did an 8 page one, and it came out very nicely as a 47 meg behemoth! That will take 4 days to email with my dialup. PM me if you would. Thanks
Neil