Compact First Stage Regulator. good? dry bleed?

[bradlw]

Looking for a cheap, simple, streamlined regulator for using on my pony
It doesn't need to be balanced but I don't want to invest even small money into something that just won't last more than a season or three...

Are these things any good?

• DGX Gears FIRST Regulator w/OPV, $69
• XS Scuba Highland Compact First Stage, $109 at Diver's Supply
• Mares R2XR 1st Stage DIN, $173 at Divers Supply
• I suppose the Dive Rite Reg Drysuit Inflation Regulator, even though it's marketed as an inflation regulator, $169 at Diver's Supply
• ...and similar

Mainly I'm wondering if these are the regulator types that expose the spring and internals to ambient seawater.

I used to have a Sherwood Brut...well actually I still have it because I have a problem in that I have a hard time throwing stuff away... I guess I thought that maybe I'll have a need to decorate the walls of a SCUBA themed restaurant someday.?.?!
Anyway
That Sherwood regulator has a "dry bleed" system...letting out a constant stream of bubbles.
I don't know if it was directly related to the dry-bleed, or what...but that regulator 1st stage didn't last very long. Internal corrosion killed it. I don't know for sure but I think it might be because I would sometimes dive with the pony tank's valve shut off so there would be no pressure in the regulator. Other than that I always try to take good care of my equipment... rinsed it well, purged it with air after diving, always carefull to keep the dust cap dry and in place, etc.... so such a short life was disappointing.

So I'm wondering if These DGX and similar regs are a similar design taht will corrode internally after a very short life on a pony bottle that gets dived but not used much.
Although at the DGX price it's significantly cheaper than what they charge to service a 1st stage...so It's disposable and why would it matter?

 

[Mobulai]

I’ll leave the Sherwood stuff to people who actually know about it, I got my 1st one (SR2) very recently out of curiosity — not sure if I’ll ever get a chance to service it leat a lone dive it

With looking at the regs you listed — I’ll safely assume they are unbalanced pistons; basically mk2 clones

The mk2 will outlive us all; I found one last year for 20€, seemed like the generation from the late 60s; it has been in a cellar for like 40 years
I cleaned it (super gunky) and serviced it in all but 10mins; instant lockup
I’ll eventually turn it to a 100% deco reg

The cheapest and most tried/reliable is an old mk2
But almost anything will work anyways, I just mentioned the mk2 as it’s super easy to diy source orings/seats for it (it’s sizes are well documented) and such

The one tip, if you go for an unbalanced 1st, preferably use a balanced 2nd

 

[Tanks A Lot]

[...]
I don't know if it was directly related to the dry-bleed, or what...but that regulator 1st stage didn't last very long. Internal corrosion killed it. I don't know for sure but I think it might be because I would sometimes dive with the pony tank's valve shut off so there would be no pressure in the regulator.
[...]

That is exactly what happened.

The ambient side of this regulator doesn't get wet. There is a check valve that only allows things to pass from the ambient chamber of the regulator to the environment, not the other way around. But that ambient chamber depends on gas slowly leaking through a tiny orifice. By turning off the gas supply, the regulator has been robbed of its ability to add gas to the ambient chamber. At some depth, the check valve will be overpowered by the pressure and water will leak past it.

Now there is no way for you to rinse that salt water out, and corrosion will make quick work of it.

Sherwood devised a very clever system here, but it wasn't perfect, and user knowledge of how it works was required. Their newer dry-bleed system with the Schrader valve is a bit more robust, but it is just as vulnerable to diving with a shut-off gas supply.

All that being said, there is very little that is truly beyond repair. Without seeing pictures of the exact nature of the damage, I would hazard a guess and say it can be restored for a reasonable amount of money.

 

[happy-diver]

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[Mobulai]

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Comes even with w 109s(maybe even converted to BA)
Great deal OP

 

[Mobulai]

Their newer dry-bleed system with the Schrader valve is a bit more robust, but it is just as vulnerable to diving with a shut-off gas supply.

So if I’m understanding this correctly, the drybleed isn’t compatible with stage usage (tank closed till needed), and that would include a pony

 

[bradlw]

Very helpful @Tanks A Lot and that's interesting the fix was a Schrader valve!

It's been a very long time since I looked at it, but as I recall it was pitting in the cylinder wall.
Seems like over sizing the bore would require a different piston? different o-ring?
or filling the pits with epoxy or something...???....

and thanks @happy-diver and @Mobulai
In years past I would have been all over trying to fix the sherwood &/or taking a gamble on an old used vintage reg. It actually sounds like fun to me to tinker.... but at my age and stage of life at the moment I'm more interested in fairly 'low-drag' and easy.

 

[bradlw]

does anyone know if these new regulators expose the internals to ambient seawater with the tank shut off?

 

[Mobulai]

does anyone know if these new regulators expose the internals to ambient seawater with the tank shut off?

You’d have to pressurize it 1st anyways (any 1st) before you go underwater, then turn it off
And as long as there’s no IP creep or a leak, the pressure would hold and keep it shut/sealed, till you need it again
(That’s the procedure for deco bottles as well)

On the off chance water ingress occurs, it’s not a biggie for an unsealed piston, unless it’s a lot that gets all the way to inside the tank

I’d still stick with an mk2 — it’s a very “no frill” reg and a good deal is easy to come by (and service is super cheap)
If you don’t come across one buying it new is maybe more expensive (so the DGX would be a better choice)

 

[bradlw]

Yeah, but that's the pitfall with the old Sherwood design...and what I'm hoping to avoid again.
If these regs are like the sherwood dry bleed design, then I suppose a diver would need to keep them pressurized for the entire dive. I suppose the only real drawback there is the potential for accidental wasted gas with accidental free-flow when entering, etc...