Scubapro chrome plated brass regulators...

[Open Ocean Diver]

Exhaust Valves:

26mm fits Scubapro metal 2nd stages 108,109, and the majority of BAs (usually blue)

33mm fits Scubapro G250 (all G series I think) and very few Balanced Adjustables. (usually black, sometimes clear)

Yep just confirmed 156, 108HP, G250

Thank you

 

[Open Ocean Diver]

NP....well, you made me go back to my bench to check another just in case I had an oddball. I'm overjoyed to say that example #2 proved to flow just as much, if not more than the first BA-cannot tell how much, as my rotameter is only scaled to 15 SCFM. If I were to interpolate the markings, the disk maxes out at over 20 SCFM. Therefore, these regs are blowing WAY past that.

Specimen #2 will not only freeflow with the tube attached, but also without. In fact, I can get it to freeflow with a sharp breath sans tube.

This is one of my favorites as it has a beautiful 109 cover (it's a BA,) a satin finish, and best of all the exhaust valve is the same size as a G250. It breathes like a dream.
(This way up ---> )
View attachment 580035
View attachment 580036

BTW When I use the term Freeflow in the context above-I mean freeflow due to venturi action-not because of too low cracking effort or a discrepancy with the tuning or a valve component.

Can’t get mine to free-flow either G or the 156 maybe needing to be tuned lower to free flow.

 

[Open Ocean Diver]

My latest invention, cuts my air consumption in half.

 

[Angelo Farina]

Can’t get mine to free-flow either G or the 156 maybe needing to be tuned lower to free flow.

When they free flow, they are out of tune, in my opinion. These regs should not free flow due to Venturi only, in air at atmospheric pressure...
Of course they should free flow in water, when facing down, or at some depth, where the air is more dense and the Venturi effect is larger. That's the reason for the knob: when they start freeflowing, you rotate the knob one turn inside, and it stops freeflowing.

 

[Open Ocean Diver]

That’s true I agree the only reg I’ve had free flowed on land after punching the purge was my D400... I had it tuned to something like .5 H2O.

 

[rsingler]

When they free flow, they are out of tune, in my opinion.

I would respectfully disagree. It varies from brand to brand, but it's a subtly designed feature. For example, every Atomic will freeflow when the purge is briefly tapped with the mouthpiece off, but will not when the slightly restricted opening of the mouthpiece is added.
Scubapro used to instruct technicians to tune the G250 vane (the one without the diver adjustable knob) so that freeflow stopped spontaneously after 1-2 sec.
Tuning a reg stiff just to avoid freeflow is a personal matter, of course, but many of us prefer our regs to breathe "whisper light", and alter technique to avoid freeflow.

And as discussed above, the whole design issue of Venturi-improved flow and lower differential pressure to keep the valve open is deliberate, to facilitate performance at higher air density.

 

[BoundForElsewhere]

My latest invention, cuts my air consumption in half.
View attachment 580149

is that a bong?

 

[Open Ocean Diver]

I would respectfully disagree. It varies from brand to brand, but it's a subtly designed feature. For example, every Atomic will freeflow when the purge is briefly tapped with the mouthpiece off, but will not when the slightly restricted opening of the mouthpiece is added.
Scubapro used to instruct technicians to tune the G250 vane (the one without the diver adjustable knob) so that freeflow stopped spontaneously after 1-2 sec.
Tuning a reg stiff just to avoid freeflow is a personal matter, of course, but many of us prefer our regs to breathe "whisper light", and alter technique to avoid freeflow.

And as discussed above, the whole design issue of Venturi-improved flow and lower differential pressure to keep the valve open is deliberate, to facilitate performance at higher air density.

Yes I now remember this from Rob my T3 with the mouthpiece off and a quick push on the purge it will free flow... I think from all the regulators made today Atomic is the true innovator so many design elements truly makes them the greatest regulator... now if we could get them to make an all metal case would be amazing.

 

[Open Ocean Diver]

is that a bong?

Yes dual purpose.

 

[BoundForElsewhere]

Yes dual purpose.

sweeeeet.

but seriously. what is that?