Swagelock QC6 source

[craig haymaker]

yes, if you push on the tip of the connector it will open the valve and release gas, it's an upstream valve and is quite difficult to connect at 100m, but still possible.
If using QC6's, the "standard" has the stems on the supply, bodies on the receiving side.

Done deal, I want to do it right, thank you Sir, for your knowledge. Craig Haymaker

 

[The Monkey]

If using QC6's, the "standard" has the stems on the supply, bodies on the receiving side.

@tbone1004 Is there a specific reason for having the male stem on the supply? The swagelok catalogue shows flow direction being from female to male. I've tried a (very unscientific) test of connecting a male and female and blowing through from each direction with my mouth and there's definitely a noticeable difference in resistance between the two directions. I would like to keep my effective Cv to a minimum, or doesn't it matter much with 10bar or so behind it?

 

[tbone1004]

@tbone1004 Is there a specific reason for having the male stem on the supply? The swagelok catalogue shows flow direction being from female to male. I've tried a (very unscientific) test of connecting a male and female and blowing through from each direction with my mouth and there's definitely a noticeable difference in resistance between the two directions. I would like to keep my effective Cv to a minimum, or doesn't it matter much with 10bar or so behind it?

stem on the supply side allows you to press the nipple against something solid to purge it if you are in an environment where "stuff" is going to get inside of it, think shore diving, stage bottles, tight restrictions, etc. If you have the female body on the supply side there is no way to clear whatever gets inside of the body and you risk blowing "stuff" into the system, or work clogging the orifice and having no flow.
Your body can only generate a couple psi of back pressure and can perceive differences measured in tenths of inches of water pressure. What you experience as a big difference becomes inconsequential at 10bar.

 

[The Monkey]

stem on the supply side allows you to press the nipple against something solid to purge it if you are in an environment where "stuff" is going to get inside of it, think shore diving, stage bottles, tight restrictions, etc. If you have the female body on the supply side there is no way to clear whatever gets inside of the body and you risk blowing "stuff" into the system, or work clogging the orifice and having no flow.
Your body can only generate a couple psi of back pressure and can perceive differences measured in tenths of inches of water pressure. What you experience as a big difference becomes inconsequential at 10bar.

Thanks. Was more worried that I had it wrong from a gas flow sense. Not so worried about "stuff" getting into female more if it's on bottles rather than rig as I use the swagelok protectors when the connection isn't mated anyway.

 

[craig haymaker]

Thanks. Was more worried that I had it wrong from a gas flow sense. Not so worried about "stuff" getting into female more if it's on bottles rather than rig as I use the swagelok protectors when the connection isn't mated anyway.

Swagelok protectors, please tell me more, as I am trying to build them!

 

[rjack321]

Swagelok protectors, please tell me more, as I am trying to build them!

Quick-Connects, QC, QF, QM, and QTM Series (MS-01-138;rev_S;en-US;Catalog) (swagelok.com)
part numbers on page 7 for
"stem protectors"
"body protectors"

The reality is they are completely unnecessary

 

[Matan]

not sure if was posted here - but fast service and fair prices so pretty good IMHO:

Tec Equipment für Nitrox, Rebreather Höhlen Tauchen

He removes unnecessary fittings so you get exactly what you need i.e. less parts.

Matan.

 

[craig haymaker]

How about I throw out this idea ! There would be however, two extra steps when connecting or disconnecting. However you could end up with pretty much “zero” water getting into your CCR side.
To connect :
1. Pull the plastic lock.
2. Slightly slide the inline valve open, to pass a small amount of gas out the male end.
3. Push the M & F connectors together!
With the small amount of escaping gas, the water contained in the small area of the female side QD, will quickly be displaced as the connection is being made.
I would say guaranteed little to NO water injected into the CCR side !
As far as will this QD pass enough gas volume; try blowing through this coupled QD as compared to the QC-4, 6.
Just an idea to toss around the good vs the bad !
!

 

[rjack321]

The CJEN fittings are unreliable, the collars often get sticky and they often won't mate across various manufacturers and lots. That's why the QC6 has become the defacto standard worldwide, they work.

Strongly suggest you not put shutoffs on your BOV.

 

[craig haymaker]

The CJEN fittings are unreliable, the collars often get sticky and they often won't mate across various manufacturers and lots. That's why the QC6 has become the defacto standard worldwide, they work.

Strongly suggest you not put shutoffs on your BOV.

What does CJEN stand for rjack? Also my Se7en’s BOV has the built in ADV, as I’m sure you know. Even de-tuned as much as allowed, it triggers fairly easy dropping fast with my BMCLs ! Hence a sliding shut off at my BOV. Please educate me on this, as I respect your knowledge Sir.
Thanks, Craig