Neoprene drysuit question.

Steve.B · April 6th, 2008, 05:19 PM

I was wondering if anyone could throw some light on this subject.

I've heard in certain circles that if you put an "Auto" dump on a compressed neoprene suit it doesn't vent properly and can cause a rapid ascent. The reason given is that the suit expands and takes the pressure of the the spring in the auto dump, and therefore you have to have a "Cuff" dump fitted

I hope this is not true, as I've sourced a really great compressed neo' suit at a reasonable price.

I've noticed that all the DUI "crushed" neo's have auto dumps but i'm talking about compressed. Anyone?

I know it would be easier to just buy a Dui but I don't have Dui money, and I would like to get back in the water sometime this year.

Cheers in advance.

Steve.

tim · April 6th, 2008, 07:00 PM

I had an O'Three RI 2100 compressed neoprene suit for a few years (sold when I, er, expanded to not fit it any more) and never experienced this problem with a shoulder autodump. I did tend, though, to dive it fully open so I'm not sure if I would ever have triggered the problem you mention. A gut instinct response would be that spare material around the shoulder 'unfolding' to accomodate more air would have a far greater effect than stretching of the material itself.

Tim

Tetsu · April 6th, 2008, 09:47 PM

I never had any problems dumping air out of a neoprene suit. Allways left the valve fully open, in auto-dump.

There are several reasons why a neoprene drysuit is not DIR, but never heard of this before...

LCF · April 7th, 2008, 03:35 AM

I have a Diving Concepts compressed neoprene suit, and my husband has a Bare compressed neo suit, and neither of us has ever experienced what you are describing.

cmalinowski · April 7th, 2008, 11:13 PM

I dive a bare compressed neo with autodump wide open and have never had a problem...

Chris

**Alastair** · April 7th, 2008, 11:30 PM

I used to have a DUI CF200 and never had any issues like you described.

Cheers
Al

Bardo · April 8th, 2008, 12:13 AM

As others have already stated, this simply isn't true. I've owned both 5mm uncompressed and a 2.1mm compressed O'three neoprene suits - both of which were fitted with Apeks autodump valves on the left arm - and I never encountered a problem like the one you've described. To be honest, what has been suggested is impossible as the mounting ring that screws onto the back of the valve would have to be physically *unscrewed* by the expanding neoprene to have any effect on the valves operation. Even then, all that would happen is that your suit would flood! That's another myth busted, I'd say...

Marijn · April 8th, 2008, 07:16 AM

I wouldn't even know how it would be possible.

The valve spring isn't in anyway retained or directly attached to the suit.
Its part of the assembly.

Even if the neoprene would expand by a huge amount, it can't even tamper with the spring, it doesn't touch the spring.

The whole dump assembly is basically stuch trough a hole in the suit and has a ring with a cover on it screwed on the end to keep it in the suit.

cmalinowski · April 8th, 2008, 10:45 PM

Quote: (Originally Posted by Steve.B)

...I've heard in certain circles that if you put an "Auto" dump on a compressed neoprene suit it doesn't vent properly and can cause a rapid ascent. The reason given is that the suit expands and takes the pressure of the the spring in the auto dump, and therefore you have to have a "Cuff" dump fitted...

You need to stay out of those circles lest you hear more stuff like this.

April 6th, 2008, 05:19 PM	#1 (permalink)
Steve.B(Offline) New Member Join Date: Jul 2007 Location: Staffs, England Posts: 33	Neoprene drysuit question. I was wondering if anyone could throw some light on this subject. I've heard in certain circles that if you put an "Auto" dump on a compressed neoprene suit it doesn't vent properly and can cause a rapid ascent. The reason given is that the suit expands and takes the pressure of the the spring in the auto dump, and therefore you have to have a "Cuff" dump fitted I hope this is not true, as I've sourced a really great compressed neo' suit at a reasonable price. I've noticed that all the DUI "crushed" neo's have auto dumps but i'm talking about compressed. Anyone? I know it would be easier to just buy a Dui but I don't have Dui money, and I would like to get back in the water sometime this year. Cheers in advance. Steve. __________________ The measure of success, is not how high you climb! But how high you can climb after you have fallen! - General Patton

April 6th, 2008, 09:47 PM	#3 (permalink)
Tetsu(Offline) New Member Join Date: Jul 2006 Location: Nieuw Vennep, Netherlands Posts: 16	I never had any problems dumping air out of a neoprene suit. Allways left the valve fully open, in auto-dump. There are several reasons why a neoprene drysuit is not DIR, but never heard of this before... __________________ Ted

April 7th, 2008, 03:35 AM	#4 (permalink)
LCF(Offline) New Member Join Date: Dec 2005 Location: Seattle Posts: 622	I have a Diving Concepts compressed neoprene suit, and my husband has a Bare compressed neo suit, and neither of us has ever experienced what you are describing. __________________ check out www.divematrix.com "So, it's a good thing to always do the drills the same way . . . but in real life you need to act the right way, whatever that happens to be." LauNar

April 7th, 2008, 11:30 PM	#6 (permalink)
Alastair(Offline) DIRX Supporter Join Date: Nov 2005 Location: UK Posts: 693	I used to have a DUI CF200 and never had any issues like you described. Cheers Al __________________ Helium is our friend - GI3

April 8th, 2008, 12:13 AM	#7 (permalink)
Bardo(Offline) New Member Join Date: Aug 2006 Location: Not close enough to the sea... Posts: 38	As others have already stated, this simply isn't true. I've owned both 5mm uncompressed and a 2.1mm compressed O'three neoprene suits - both of which were fitted with Apeks autodump valves on the left arm - and I never encountered a problem like the one you've described. To be honest, what has been suggested is impossible as the mounting ring that screws onto the back of the valve would have to be physically unscrewed by the expanding neoprene to have any effect on the valves operation. Even then, all that would happen is that your suit would flood! That's another myth busted, I'd say... __________________ Honourary member of the Tufty Club... Last edited by Bardo; April 8th, 2008 at 12:16 AM.

April 6th, 2008, 07:00 PM	#2 (permalink)
tim(Offline) Big Grin Syndrome Join Date: Dec 2005 Location: Oxford Posts: 453	I had an O'Three RI 2100 compressed neoprene suit for a few years (sold when I, er, expanded to not fit it any more) and never experienced this problem with a shoulder autodump. I did tend, though, to dive it fully open so I'm not sure if I would ever have triggered the problem you mention. A gut instinct response would be that spare material around the shoulder 'unfolding' to accomodate more air would have a far greater effect than stretching of the material itself. Tim

April 7th, 2008, 11:13 PM	#5 (permalink)
cmalinowski(Offline) New Member Join Date: Dec 2005 Location: Columbia, MD--USA Posts: 175	I dive a bare compressed neo with autodump wide open and have never had a problem... Chris

April 8th, 2008, 07:16 AM	#8 (permalink)
Marijn (Online) Smurf #1 Join Date: Aug 2007 Location: Papendrecht, The Netherlands Posts: 379	I wouldn't even know how it would be possible. The valve spring isn't in anyway retained or directly attached to the suit. Its part of the assembly. Even if the neoprene would expand by a huge amount, it can't even tamper with the spring, it doesn't touch the spring. The whole dump assembly is basically stuch trough a hole in the suit and has a ring with a cover on it screwed on the end to keep it in the suit. __________________ Its a fact that the humans can't go without water for more than 3 days

April 8th, 2008, 10:45 PM	#9 (permalink)
cmalinowski(Offline) New Member Join Date: Dec 2005 Location: Columbia, MD--USA Posts: 175	Quote: (Originally Posted by Steve.B) ...I've heard in certain circles that if you put an "Auto" dump on a compressed neoprene suit it doesn't vent properly and can cause a rapid ascent. The reason given is that the suit expands and takes the pressure of the the spring in the auto dump, and therefore you have to have a "Cuff" dump fitted... You need to stay out of those circles lest you hear more stuff like this.