Drager Dolphin: cylinder options

4ster

Dolphin divers,

Seems to me that the 4 liter bottles are a tad too small. 5-6 liters would be a better size in that you can get about 2 hours (2 dives with my OC buddies) on the 50% jet. I can't find 5-6 liter cylinders in my neck of the woods that work in the Drager cross mount configuration.

My ideal bottle:
5-6 liters
Steel
Drager valve (1 less part in the system if I don't have to use a DIN to Drager converter)
DOT (or Canadian counterpart) stamp so I can fill it here in the states.

I can't get the Drager 5 liter bottles though my scuba suppliers here in Washington State. I am not sure why, maybe because they have not been DOT certified?

So far my best option seems to be a Luxfer AL S050. This is about 6.9 liters and is short enough so as not to be too ungainly. I am not sure I would like the change in bouyancy with that large of an aluminum "bubble" on my butt.

I would be interested to hear what you folks are using on your Dolphins.

Steve

JonORunde

I have used both 5L and 6L steel-bottles on my Dolphin.
I do use the converter. -Alternately, Martin @ tecme has replacement DIN-plugs for your Dolphin 1. stage -Same amount of parts...

Now I plan to use two 6L-bottles, one on each side of the nice steel-chassis I have gotten my hands on... The trim is much nicer now...

But, plain old plastic-shell with 6L steel, has worked excellent for me.

Jon O

Freef

I'm using the 5L steel tank from Drager, while waiting for my 10L H valve to arrive.

Be aware that diving a big tank doesn't let your gas outlast the scrubber duration though. One option is to decant from a 12 or 15 into the Drager tank.

The better option is to work out your vO2 and use gas/jet matching to get longer duration dives. I almost always use 40% through the 60% jet.

I have posted the formulae elsewhere on here.

__________________
David.

Currently owner of two differently sized ankles.

4ster

I'm too new at this to start diving the Dolphin "off label". I want to first dive it as the manual directs, building a seat of the pants feel for what is going on. Then I'll think about using different jets with different mixes.

My main point in this thread is that there doesn't seem to be as many options for Drager divers in the states for different cylinder sizes. I would love to get my hands on a 5 or 6 liter steel cylinder. Who sells them in the US?

jswensva

I've sold my Dolphin, but when I was diving it I had an Asahi HP 80 (still have this tank if anyone wants to buy it ) that fit nicely across the back and got some weight off of my belt. It's about 22" wide or so and fit flush with the edge of a 13 mounted on the side for inflation. I think the equivalent metric is about 10L.

jbscuba

Has anyone dove the Dolphin in the northeast? If so, to what depths have you dove it, using what mixes?

curator

In the UK Faber do 5 litre steel cyinders which I use on my Dolphin and are ideal (Size and Weight). But I'm not sure if you can get them in the US, (it may give you a start in your search).
W+S Safety (AKA danshop) in Germany do a variety of valves, including the Drager fitting which would fit the fabre cylinders and avoid the use of an adaptor.

I hope this helps

Curator

4ster

I found a 5.7 liter steel cylinder! It is a long story, but it serindipitously just bumped into me. I had ordered an AL 50 30 minutes before I found the steel bottle! Order canceled.

The steel bottle is being O2 cleaned at my favorite dive shop right now. I am guessing it is a Faber, but in my excitement I forgot to check. I will follow up if anyone wants to know more details.

Steve

zèècalcoene

Hi Steve,

I don't want to be rude but before you purchase new bottles, just think ahead about a year.. After this time u would/will/want to consider to rebuild yr unit to mCCR..This of coarse depends the type of diving you're in.

If yr kind of diving is unpredictable in terms of depth, you will seldom find yrself with the best nitrox mix..for those depths.

Think a little bit ahead, talk to yr Dolphin Instructor and go through the possibillities for an advanced training (after yr SCR training)..mCCR..KISS Rebreather training.

I was in the same situation 2 yrs ago.. found myself buying different bottles and in the end I only needed 2*2 ltr steel bottles and a bigger (10l-300bar carbon) bailout..

Now I am stuck with 4, 5 and 8 ltr original Drager bottles..which are damn expensive..money I could have used for the mCCR conversion..

Just my thoughts

Ivan

4ster

Not rude at all, thanks for the comments.

As a begginer in this I will be diving the Drager as per the manual. As I gain experience I will assess the Drager's limitations and the training I need to expand them. For now I want the option of a bit more gas.


Steve