Brut for stage bottle

I have been considering getting a Brut reg for a stage bottle. Can you get the first stage with a DIN? Is the Brut a "bleeder" type, so after you pressurize the reg, it will lose the pressure to the second stage?
Thanks.

Yes you can get a DIN brute. Yes, all sherwood regs are "bleeders" the way they work uses a slightly overpressurized ambient chamber that leaks a continuous stream of tiny bubbles instead of allowing water into the ambient chamber. Leak rate is maybe .25 cf/hr.

For years, I've used only Sherwoods and have come to love the "Dry Air Bleed" design and its dry ambient chamber. It bleeds off at the 1st stage. The 2nd stage is unaffected.

Per specs, the design will "bleed" about 15-30cc/min and I've never seen more than that. If my arithmetic is correct, 30cc/min would mean a loss of about 0.07 cu ft per hour, so it's insignificant, as stevead was implying.

Presently, I use Sherwood Blizzards for my primary and for my pony, but have used Bruts and Magnums, too. They are all excellent and basically the same design, except the Brut is not a "balanced" design, whereas the others are.

All perform very well at recreational depths, IMHO.

Plus, they are all very easy to service and they can go a long time before needing servicing.

The DIN adapter is simple and reliable and takes less than a minute to install.

All things considered, the Brut would probably make an excellent stage bottle regulator!

Dave C

I just converted my brut stage reg to DIN. Simple task. Now just have to go and take the tank in for vis so I can put the new DIN valve on.

Thanks for all the info!

I use a Brut on my stage / O2 bottle. It works fine. I have the DIN adaptor on the reg. When I first picked this reg up I too was worried that it would bleed the pressure on the first stage down after I pressurized it. As it turns out, the dry bleed is so slow that I have not had a problem. Even after a 50min. or so dive I only lose maybe a few hundred PSI.

Dive1Dennis:

I use a Brut on my stage / O2 bottle. It works fine. I have the DIN adaptor on the reg. When I first picked this reg up I too was worried that it would bleed the pressure on the first stage down after I pressurized it. As it turns out, the dry bleed is so slow that I have not had a problem. Even after a 50min. or so dive I only lose maybe a few hundred PSI.

Click to expand...

EDIT: I realize now that the OP and Dive1Dennis were not concerned about overall loss of volume, but that they were considering whether the loss would be enough to un-charge the regulator after it was shut off. Sorry about that....and I was having so much fun with the arithmetic, DARN! End EDIT

Even at a 30cc/min bleed rate, only 0.07 cubic feet of gas is bled off each hour.

30 cc (cubic centimeters) per minute bleed rate (typical bleed rate is 15-30cc per minute)
30 X 60 = 1800 cc per hour bleed rate

1 inch is 2.5cm (centimeters)
1 foot is 12 X 2.5 = 30 cm
1 cubic foot is 30 X 30 X 30 = 27,000 cc (cubic centimeters)

1800cc (bleed rate per hour) / 27,000cc (cubic centimeters in 1 cubic foot) = 0.067 cubic feet or roughly 0.07 cubic feet per hour bleed rate

On a 3000 psi 40 cf bottle, a loss of 0.07 cubic feet of gas will lower the psi by only a tiny amount:

0.07 / 40 X 3000 = 5.25 psi drop for that tank in one hour from the bleeding off of air

I'd suggest your psi drop of a few hundred psi in less than an hour is due to some other factor, such as a drop in temperature perhaps.

Someone please feel free to check my arithmetic in case I've made a total buffoon of myself!

EDIT: One thing I forgot to add was that the increase in ambient pressure at depth would probably increase the output of the "flow control element" to some extent, although, with the sintered metal element, it probably wouldn't be proportional. End EDIT.

Dave C

dave4868:

Even at a 30cc/min bleed rate, only 0.07 cubic feet of gas is bled off each hour.
......
Someone please feel free to check my arithmetic in case I've made a total buffoon of myself!

Dave C

Click to expand...

Dave, a slight misunderstanding perhaps. I charge the stage bottle reg at the start of the dive by turning on the gas from the tank and then shut the gas off again during the dive until needed for deco. The PSI drop is from the reg. only. I'm guessing your calculations are right, but you would need to use the volume in the regulator only, not 40 cf.

We are all good! :14:

Dive1Dennis:

Dave, a slight misunderstanding perhaps. I charge the stage bottle reg at the start of the dive by turning on the gas from the tank and then shut the gas off again during the dive until needed for deco. The PSI drop is from the reg. only. I'm guessing your calculations are right, but you would need to use the volume in the regulator only, not 40 cf.

We are all good! :14:

Click to expand...

Right you are, thanks for clearing that up for me!

I now see that the OP was probably asking about the same thing. My post shows my ignorance, since I don't use stage bottles and keep my pony valve open throughout the dive.

I see there could be some concern about a charged, but shut off, regulator bleeding down to zero, but you've demonstrated it's far from likely. Now I see the point you were making.

I also need to edit my post above to reflect the increased actual volume of air lost due to increased ambient pressure at depth which is likely to increase the output of the bleed "flow control element".

So many mistakes to be made....so little time....

Dave C

Thats interesting about the bleed not completely draining the 2nd stage hose. I have used a sherwood reg for my pony (not stage) and I was leaving it on because I was worried about the second not staying charged. That is good to know.

Thanks
Phil