Neoprene Counterlung, whats the big deal?

[KentCe]

What is the advantage of constructing a counterlung out of neoprene? Just wondering why some rebreathers use neoprene for the counterlung and others don't.

[madmole]

Cheaper and easier to make than a dual bag construction

But, can also be tidy and potentially the neoprene offers some insulation to the loop gas

In my Inspirations case the neoprene Lungs I have are smaller and much neater than the APD counterlungs.

They also remove very quickly and easily for disinfecting

S

[DrySuitDave]

One of the things I have noticed is it seems as if the abrasive cordura sides of my factory counterlung rub thge crap out of the side of my neck, which does not bode well for tropical diving.

It would seem neoprene would be softer, but what about the strength, such as overinflation..do they ballon up or do you open up the overpressure valve, which raises the issue of positive pressure loop checks.


Lastly, is there a supporting nylon web that goes behind each lung so when you lif the unit by the lungs, it doesn't stretch out and strain the counterlung?

[padiscubapro]

madmole once bubbled...
Cheaper and easier to make than a dual bag construction

But, can also be tidy and potentially the neoprene offers some insulation to the loop gas

In my Inspirations case the neoprene Lungs I have are smaller and much neater than the APD counterlungs.

They also remove very quickly and easily for disinfecting

S

Thank God during my dives last week I didn't have neoprene lungs.. I was diving in warm water (81 f) and most dives involved swimming against a stiff current.. even with no insulation the loop at times became very unconfortable to breathe... The high co2 load being removed with a high breathing rate really had some hot gas in the loop.. I ALMOST considered going to OC so I could cool down... I ended up just relaxing for a few minutes and let the loop cool down.... Nice thing not having to worry about gas consumption...

[caveseeker7]

madmole once bubbled...
In my Inspirations case the neoprene Lungs I have are smaller and much neater than the APD counterlungs.


Are those the lungs from Innerspace? How is the finish?
Did you just replace the APD ones or have you already added the 2nd loop?
S.

[KentCe]

Given the rough surface of neoprene, I wonder about problems keeping it clean inside.

[madmole]

My neoprene lungs were custom made , they are not the Ineerspace one's

The do indeed have nylon web across the back to support them and hold them tight on my harness

The inside are smooth neoprene (like wrist seals) se easy to keep clean and as they are far easier to pop on and off you are more likely to disinfect them

The dump valve is an APeks dry suit valve modified so that hen screw right it it completly locks the flow so yo can do the presure tests, Just like a dry suit I now have auto dumping of loop volume on way up. no more hampster cheeks for me. Coupled with ADV I now have auto up and down and my unit always is at minimum loop volume

When I reach the surface or gnerally want more air in the loop I just shut the dump a bit, just like a dry suit

Overheating in the water just isn't a problem in the UK. I have neoprene on all my hoses and scrubber to keep it as warm as possible!!!!

If work and diving ever allow me a day off I'll try and get some photos up on my site