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Autodumpers only. - Cuffers take five.

  • Suit for buoyancy and ascent

    Votes: 0 0.0%
  • Ease the squeeze and wing for buoyancy and ascent.

    Votes: 0 0.0%

Autodumpers only.

1K views 21 replies 16 participants last post by  Paul Bogle 
#1 ·
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OK. A question for all you autodumpers. Bye the way this is just to make you all feel important because us cuffers know we are doing it the right way.

Anyway, I am particularly interested in hearing from anyone who has managed to set their autodump so that they can ascend from bottom to surface (safely) without playing with it.

[EDIT] IN THIS POLL

BUOYANCY = CONTROL DURING BOTTOM TIME ONLY.
 
#2 ·
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Dont see what diferance it makes what dump system you use? I use wing for boyancy control and suit for keeping warm, as God (and the designers of said items) intended


As fo auto dump I just set it at max and ignore it untill I hit the 6m stop. Then I do it up a couple of turns and stich a shead load of air in the suit to keep warm.

Mark Chase
 
#4 ·
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I only use my suit for bouyancy. I only touch my dump valve twice a dive. Once as I near the bottom I close it a couple of clicks and then open it just as I leave the bottom fully again.
Don't need to do this but it makes wriggling about easier as I don't dump air when moving around and I put the valve higher than the rest of me
 
#5 ·
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[b said:
Quote[/b] (Mark Chase @ Feb. 12 2004,16:07)]Dont see what diferance it makes what dump system you use? I use wing for boyancy control and suit for keeping warm, as God (and the designers of said items) intended


As fo auto dump I just set it at max and ignore it untill I hit the 6m stop. Then I do it up a couple of turns and stich a shead load of air in the suit to keep warm.
Mark,

You are quite right, however, I am under the impression from many previous posts on here, maybe mistakenly, that autodumpers unanimously "ease the squeeze", fine tune with the wing and prior to ascent fully open the autodump and ascend using the wing.

To the contrary, cuff dumpers, all use their suit during the dive and for ascent.

I stress these were the impressions I thought seemed to be unanimous. Then John Gulliver informed me on D/net that he has an autodump and uses his suit for buoyancy throughout the dive.

I'm just trying to get the feel for how you autodumpers work - I was expecting nearly every autodumper to vote for the same option.

How does that reach 6m and stick shed loads of air in to keep warm work - don't you hit the surface a bit promptly?

Rgds
Bryan
 
#6 ·
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[b said:
Quote[/b] (Finless @ Feb. 12 2004,16:25)]How does that reach 6m and stick shed loads of air in to keep warm work - don't you hit the surface a bit promptly?

Rgds
Bryan
If I am staying at 6m for any length of time that meens I have stages with me probably two. Asuming I havent had a problem during the dive I am still in posesion of all my ditchable equipment and my back up gas reserves. With all that on I am over weight. Soooooo dump all air from wing and fill suit to hold 6m and keep warm.

If I have had a total disaster of a dive I will have used all my spare gas and / or lost / dumped my stages, my tourch, my primary reel and SMB back up knife etc etc. Then I will be at 6m with no air in the wing and very little air in the suit with a yellow blob up praying for a drop tank


ATB

Mark Chase
 
#7 ·
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Hmm...I was under the impression that it didn't matter how much air was in the suit - it was the undersuit that kept you warm.  Does it make a big difference or just noticeable enough that it's worth doing?

As for the autodump, I leave it wide open all the time.  No more difficult than a cuff dump.

cheers

r
 
#8 ·
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[b said:
Quote[/b] (Mark Chase @ Feb. 12 2004,16:51)]If I have had a total disaster of a dive I will have used all my spare gas and / or lost / dumped my stages, my tourch, my primary reel and SMB back up knife etc etc. Then I will be at 6m with no air in the wing and very little air in the suit with a yellow blob up praying for a drop tank
Mark,

That all makes sense.

I have decided not to buy a yellow blob to prevent me ever needing a "bottle from above".  


Rgds
Bryan
 
#9 ·
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[b said:
Quote[/b] (Juz @ Feb. 12 2004,17:10)]Auto on left shoulder, fully open the whole time, only dumps when I roll to my right or lift my arm.

Suit is used throughout the dive - only use wing at the surface.

Juz
Same same!
 
#10 ·
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[b said:
Quote[/b] (siltmonkey @ Feb. 12 2004,16:56)]Hmm...I was under the impression that it didn't matter how much air was in the suit - it was the undersuit that kept you warm.  Does it make a big difference or just noticeable enough that it's worth doing?

As for the autodump, I leave it wide open all the time.  No more difficult than a cuff dump.

cheers

r
Depending on your undersuit it makes a BIG difference. The undersuit traps air/wicks sweat away - no/less air = less heat retention.

I tried once dumping air from suit and ascending using my wing - apart from the fact I was up and down like a pair of knickers belonging to someone with chronic dio.. dia..., the shits I was ALSO bloody cold during deco.
 
#11 ·
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[b said:
Quote[/b] (siltmonkey @ Feb. 12 2004,16:56)]Hmm...I was under the impression that it didn't matter how much air was in the suit - it was the undersuit that kept you warm.  Does it make a big difference or just noticeable enough that it's worth doing?
Its all about heat transfer. Weezels need a lot of air to work to full eficiency and Thinsulate dont need as much. More air in the suit does make a noticible diferance but I wont risk it during the dive and generaly I dont need to. I am mooving and keeping warm that way.

Deco is a static event and not much can go wrong at 6m. If it does you either go up or down. Both events are not that serious if handled properly so risking a suit full of gas on the 6m stop is usualy a small risk at my level of deco diving.

ATB

Mark Chase
 
#14 ·
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<font color='#000080'>I was taught and use:

Suit for boyancy and to keep warm. I deflate my BCD at the surface to decend. I keep my Autodump half open so if I make a complete twat of a manouver under water I don't loose all my suit boyancy/air, but also don't start to accelerate to the surface due to a closed Dump and therefore complete inability to dump at all. I then gradually pump air in my suit as I decend to maintain neutral boyancy. When I bottom out I open my Autodump fully and as I accend slowly throughout the dive I just roll to the right slightly to dump as and when I feel slightly positively boyant to return to neutral boyancy. I only every use my BCD whilst on Holiday in my wet suit and at the surface to lift my head out of the water if waiting to the pickup. I find I'm warm enought in my mid sized Weezle and only cold if the fresh water thormocline on the top 6m of sea loch is chilling.

Dave C
 
#15 ·
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<font color='#000F22'>Mark or others,

Do any of you use argon for your suits. The reason I ask is I have an argon bottle lying in the shed, given to me but never used by myself. Is it the placebo affect or does the increased molecular density actually have a noticeable effevc in terms of a reduced heat transfer coefficient? i.e does it keep you warmer!!
 
#17 ·
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<font color='#000080'>In my very short drysuit career, I've found that leaving the autodump half open, BCD empty on descent, gives me a nice steady descent rate. At depth just a touch of air to the suit to get neutral. By closing the valve by one or two clicks ensures good dumping. Occasionally with the shoulder valve at the highest point have to tuck my elbow right in though to lose any excess air, but I think this might be a "feature" of the Aerdura!

Ascent - valve back to fully open dumping air on the way..
 
#18 ·
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Autodump fully open throughout dive, the air rarely seems to escape unless I purpose fully tilt or ascend. BCD for surface and then suit for the rest of the dive.

I usually press autodump purge button as I ascend from 6m(ish) to surface and pump my arm to ensure all remaining air has been purged. If I need to I put a couple of fin strokes in to ensure I continue my ascent. Once on the surface I inflate BC.
 
#19 ·
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[b said:
Quote[/b] (Reeve @ Feb. 12 2004,23:19)]Mark or others,

Do any of you use argon for your suits. The reason I ask is I have an argon bottle lying in the shed, given to me but never used by myself. Is it the placebo affect or does the increased molecular density actually have a noticeable effevc in terms of a reduced heat transfer coefficient? i.e does it keep you warmer!!
No  I dont but Andyp does. I cant be assed with ANOTHER first stage and tank to maintian. I just run the suit off of deco gas.

As for does it work the answer has to be yes as its scientificly proven. However if the question is does it work with a dramatic noticible effect my answer is no. Some may dissagre but I tried it and didnt go 'wow I must have this'. I went 'errrrrrr is that it'


I beleive I read it is 0.6 times more dense than air and the 60% just isnt all that noticable IMHO

Mark Chase
 
#21 ·
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Hi,

I had ignored this thread, but in an idle moment at work, I obviously read it.

We have been round this one several times in the past, but;

there are a couple of realities we have to deal with, once we have a twin set, two stages, a canister torch, two reels a spare mask and Uncle Tom Cobley attched to us there is bugger all chance that the suit alone will give enough lift to get to the surface (I know the DIR boy's will argue - don't bother). Once this realisation hits you, you change your style, I did.
I touch the autodump 4 times each dive, it is wide open when I jump in, pretty much as soon as I start decending I close it a couple of twists, I have it set so under normal conditions no air gets out, but, if I need to dump some I just kinda give myself a hug (cos I luv me) and it will let some out.
Once down I fly the wing, much better control, plus the design of the wing holds me in a nice comfy position, as opposed to haveing loads of gas in the suit slopping around. There is enough in the suit to remove the squeeze.

At the end of the bottom time, I throw up the blob and take a twist off the dump, this for the most part allows the excess gas out on the way up, with the occaisional hug.

At 6M like Mark I dump air out the wing and fill the suit. We have had to sit there for a considerable time, you are not moving about much, it gets cold, air is a better insulator than no air.

As for Argon, I have it, the critical thing is to remove the air out of your suit, if you do that then it makes a huge difference, I now dive a compressed neo suit with a very thin under suit and have kept quite warm. Though to be honest I have not had to do a long hang this winter so I don't know how I would feel after that. Most people who use Argon don't vent the suit at the begining, this is the reason I have the dump fully open when I jump in and only close it when I begin to feel a squeeze.

Take care all,

Andrew
 
#22 ·
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When I started I used (as I was taught) the suit all the time - dumped all air from BCD at surface. With the auto dump fully open I found it wasn't dumping air fast enough on ascent so now I'm just inflating the suit to stop the squeeze and using my BCD for bouyancy. I still leave the auto dump fully open and it's been fine so far.

Paul
 
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