Use of onboard 1st stage as a manifold and q about QC6

womble

I'm thinking about using my onboard dil 1st stage as a manifold and running a whip off it to connect up to offboard dil/bailout.

ARe there any drawbacks to using the 1st stage as a manifold?

Im also thinking about using Swagelock QC6's. Which way round do they go? The diagram on the info sheet from Swagelock says the flow goes from body (female) to stem (male). Is this the only way they can work or can they be used the other way round?

Are checkvalves needed?

cheers,

Pete

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Dave Sutton

Hi Pete,

This is the method I have been using for years and it works well. Simple to implement: Just turn on one bottle and turn off the other... simple = good. If you feed your BOV from the same first stage, whatever gas is on the ADV is also on the BOV.

I use CEJN connectors (Drysuit and Air-Source connectors) running thru a checkvalve. With DESO (Double End Shut Off) quick connects there's probably no reason to use a checkvalve, but it would never hurt. Just make sure the flow rates are adequate. If you use Swagelok QC's you can really run them in either direction. For widespread compatability with other rigs, the socket on the rig and the male on the cylinder would set you right.

Dave

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Drmike

i use male on rig and female on stages as the qc6 male is quite exposed and easy to mess up. i figure male on stages is easier to damage when stages get thrown around and male on unit is not going to get thrown around. swagelok supply protective caps but i dont bother useing them in the end, although prob should as it can be fun when the stage has been dragged through cave mud and the connector is full of sticky clay

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Lancer4545

Hi Pete,

I can't see any problem with using your first stage as a manifold for the input of off board gas. In fact I see it being a very simple answer to it. There is no need for a check valve providing you don't intend sharing your offboard gas with someone who has bailed out as it could run your dil down if they are both connected and opened up at the same time. Other than that there is no way for either tank to cross feed and ballance as the first stage HP valve and seat will take care of this.

The only limitation with this set up is if you decide to add a BOV or FFM....then you will run out of ports and will be better off looking at another alternative.

Regards,

Lance

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ERIK A

Dave,
Do you happen to have a picture of this setup. Did I miss it on your website?


Erik

womble

Thats fantastic guys, all my questions answered. If everything in life was that easy!!

Cheers,

Pete

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Dave Sutton

Uhhh.... search here in the rEvo forum for the thread titled "Nice Pair" and therer are some photos and details of an earlier system I made, but it's been recently superceded by a simpler one. I need to write an article on the subject as I've recently been building and showing some offboard manifold setups that are integrated with the BOV and allow the following three configurations:

1: On board feeds rig and BOV

2: Onboard feeds rig, offboard feeds BOV

3: Offboard feeds rig and BOV


The system uses one hose, one checkvalve, and one ball valve and connects to the onboard first stage, and relies on using the first stage body as a combining manifold. I'll detail it out later. AnneMarie (AM) just dove it and commented on it in the recent Andrea Dora thread, and Mark Nix (Klondikediver) has seen and copied it as well. Ask them too.


Dave

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kybrt

photos david we demand photos, even just cell phone ones.

i have a manifold from lance robb <l;ancer 4545 > i was going to use, i welcome your suggestions as always.

my thought was from first stage over shoulder to slider, then to a y block, then up to manifold that connects everywhere, slider open/offboard closed and onboard feeds everything, slider closed/offboard open/onboard open, dil add is with bov, then offboard open,slider open,onboard closed dil adds thru reg/onboard button.

offboard o2 feeds from a button like paul uses for solenoid.

plus the manifold has a cejn and a qc6 on it, so you have every type of connector plumbed so anyone can donate gas.

belt,suspenders and kitchen sink,no?.

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Dave Sutton

All will be revealed. I'll shoot photos when I get back to the LDSOH and will write it all up. Off diving for a bit, back Monday-ish.
It's a very simple system, but easier to show than to describe.

Piece of advice: When things like my drysuit and the air source on my wings (fed with 02 as an emergency open circuit 02 pathway) and my BPV connector all magically become QC-6 fittings, I'll use Swagelok. But since they are all CEJN and since plug and play 'every gas available to everything' is the basis of building a fully redundant and reconfigurable system, I'll stick to CEJN. Teaser: My system allows me to cross-deck 02 and diluent, meaning that if I blow the entire 02 pneumatics system on my rig, for example, I can plug the 02 to the diluent side of the rig and magically my old diluent manual add valve becomes an 02 manual add valve (or vice versa). Very redundant system with very low parts count.


Dave

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ERIK A

Hey Dave appreciate the link.


Erik