Gas switching

[Hamlet]

Need help locating a company that manufactures "gas swtiching" manifolds or blocks. I'm talking about the kind that are worn on the front of the diver for use with a FFM. Three inlets one outlet, and yes before anyone brings up any safety issues. In case of failure of FFM reg each suppy will have it's own second stage as well.

 

[trymixdiver]

I was using a FFM and custom side block (aka gas switching manifold). I dove it for about 2 years with no problems. However, its not a perfect system, there are issues.

1. If its always connected then you risk bumping or having a valve leak your deco mix into your bottom mix. I dont need to tell you the results of that.

2. Your adding alot of complexity

3. Your complicating Gas sharing in an emergency

4. If its not perminently attached ( like mine was) then your gonna need quick disconnects to plug in when you do what to switch gases. I dont care how careful you do it, your gonna introduce water into the hose every time you connect and disconnect.

I worked on mine for a long time and dove it alot, and to be honest its very lucky that im even here and able to warn you that its not worth it.

I am advising you to keep it simple and not to try it.
Do a Search with "what full face mask" and read my old post and its comments PLEASE.

Andy

 

[trymixdiver]

the FFM faulire issue you bring up is the least of your worries with that manifolded system.

If it was perfect, the DIR folks would be doing it!

Andy

 

[Hamlet]

Thanks for your reply, but not everyone is DIR, there's quite a few out there who are DIW. You might say, the thing no one can convince me of with DIR is a reliance on your buddy, (I'm sure you'll correct me if I'm wrong) I for one would not want to put that kind of responsibility on anyone. However the keeping it simple solution is no doubt a good one. I just wanted a company name, I did not want to get into the DIR debate.

 

[MikeFerrara]

If...I could solve the gas switching and air sharing problems, I would use a FFM. Communications would be great (if it worked with He) and in the event of a convulsion you might live.

I have seen the valves you mention but don't recall the name. It didn't seem to me that they solved the problems though.

I have thought of using a FFM for 20ft on O2. That might work well for cave dives as we drop the bottle.

 

[roakey]

Is this what you're looking for?

http://www.sarind.com/acatalog/rsv.html

Roak

 

[trymixdiver]

hamlet

this isnt a DIR issue, its common sense.

It can be done, its just not safe diving.

The only way to switch gases useing a FFM is to:

1. use quick disconnects which introduce water inthesystem - BAD

2. have it perminently connected trusting that the valvewont leak your deco mix into your bottom mix, or that the valves o rings are not leaking due to corsion from the water your letting in.

no DIR debate here, i was using them as an example. All i am saying is your complicating your rig, Keep it simple.
Andy

 

[ericfine50]

Sartek has one, the RSV-1, so does Kirby Morgan for the band masks. I think he now has a full face mask that can swap out 2nd stages or Pods, I think. What is the reason for the FFM? Cold, contaminated, Search and Rescue stuff?

Eric

 

[Hamlet]

First of all thanks for the replies and advice, I’m having second thoughts about the suitability of FFM’s for this kind of diving, guess like a few of you out there I started diving the AGA FFM and thought this is great how can I use it for all my diving? Looks like the answer is you cant, at least not safely.
OK Andy your right this is not a DIR issue, but do you really think "If it was perfect, the DIR folks would be doing it", is any system that good?

 

[Uncle Pug]

Hamlet once bubbled...
OK Andy your right this is not a DIR issue, but do you really think "If it was perfect, the DIR folks would be doing it", is any system that good?

*DIR folks* covers waaaay to much territory.

First you have WKPP trained DIR folks
Second you have your GUE trained DIR folks
Then you have your DIR mentor trained DIR folks
Then you have your internet / guru trained DIR folks
Then you have.....

Well... the point is... the ones Andy is correctly referring to is the WKPP... if using FFM gave any advantage in achieving their object or enhancing their safety then they would be using it.... and the trickle down would hit the other groups as well.

That said... I seem to have heard somewhere that JJ does use a FFM for deco on high PO2. They also use habitats.