Wednesday, June 8, 2016

2. Service and First Dives

I spent this past weekend with Course Director John Lachelt at Giglin’ Marlins in Houston. John is a Dolphin expert and one of the original factory trained technicians for the unit. He also previously owned a shop in Juno, Alaska, where he had a fleet of rental Dolphins. John is the man to see if you have questions about the Dolphin, and I’m lucky to have found someone nearby that was familiar with the unit. John and I started out testing and servicing the machine, and we immediately replaced the bypass hose which had split from being crimped in the box for 17 years. After a full going over, we put the unit in Giglin’s 14 foot pool for a test flight. John had one of the factory 100% orifices, and I had to try it. We topped off one of his original Drager 27cf cylinders with 02, and I eagerly jumped in.  I was surprised how slow the flow rate was using 02, vice the other orifices, and it flows at only between 1 and 2 lpm.  In the water, the Dolphin performed flawlessly.  With the exception of a leaky BC LP inflator, all else checked out perfectly. I was amazed how little the unit vents on 100 percent 02.  It truly feels like a CCR, and it’s actually quieter that my CCR’s. Of course there are limitations to the pool orifice, but using it in the pool is as close to a true CCR experience one can get with a SCR. Sunday we headed out to 288 Lake for a few dives. We switched to the 60 percent orifice, and although the gas venting was much faster than using 02, I was generally pleased with how it performed.  I had only dived a Dolphin previously with 32 percent, and switching to 60 percent was quite a noticeable improvement.  Other than the biting perch and the low viz, the dive was quite enjoyable.  It was fun to get back on the unit, and I now look forward to some mods for it, and introducing some other divers to this classic machine. Next up, we will replace the “boat anchor” of an SPG with a more modern one, as well as adding a PO2 monitor connected to a Shearwater computer.

The original Bypass hose was cracked having been crimped in the box.


New Miflex hose and connectors


New hose is attached
Visit our website at www.eliteprodive.com for more Drager Dolphin information and training

Thursday, June 2, 2016

1. The New (Old) Drager Dolphin

Welcome to my old school Drager Dolphin Project.  The idea of this project actually began a while back when I was teaching a CCR course, and explaining differences between the modern-day electronic CCR’s and the early recreational SCR’s. The conversation turned to the Drager Dolphin, its simplicity, and how it functioned as an entirely mechanical rebreather. I later found myself reminiscing about my time on the Dolphin, and how far rebreathers had advanced in such a short period of time. I thought how nice it would be to have a functioning Dolphin to use as a teaching tool, and also as an easy way to introduce divers to rebreathers. I've found that a lot of open circuit divers are interested in rebreathers, but many are not ready to make a $10k investment in a CCR. Many just want to try a rebreather, and what a better way to introduce them with a Dolphin.  The benefit to me would lower operating and maintenance costs compared to using my CCR's for discover sessions. Only one problem, Drager stopped making the Dolphin (and parts for it) many years ago. The Atlantis/Dolphin is still listed on the PADI continuing education flow charts, so I figured there must be people around still diving it. But what I learned was that although it is still very popular in Europe, the rebreather has all but vanished from the United States. It seems as though technology has pushed the Dolphin aside. And I get that! Nobody’s carrying around a 1990’s cell phone, and rebreather divers have moved on to more advanced machines, myself included.  I started by searching the internet for any Dolphin clubs or groups for support, but there were none to be found. I figured that if I was going to do this, I was going to be on my own, or so it appeared.  So I began by searching the internet for used machines. I found a few for sale, but all had seen better days and most looked way too scary to dive. I had all but given up on the idea, until one day...there it was...a brand new Dolphin, still in its original packaging. It was at a pawn shop in Minnesota, and I don’t think they really knew what it was or what they had.  A couple of emails, a phone call, and the Dolphin was at my doorstep.  So, this is where we began.  A journey to add some modern updates to the Dolphin, re-live some old experiences, introduce and teach a new generation of divers about our rebreather history, and of course, to bring this 17 year old Dolphin to life. So follow along over the next few months as we
re-explore the Drager Dolphin.




The original Drager case

Like opening a time capsule


Drager BCD



Scrubber canister 

Drager piston first stage. dosing unit with 40, 50, and 60% orifices, and a very
old school SPG. Step one, service the first stage and the bypass.

LP Inflator hose, flow meter, and fill adapter. No cylinder came with the unit, so
one of the first priorities will be adapting the M24x2 connection on the first stage to
a DIN cylinder. 

Dive/Surface Valve

Exhalation Counterlung

Inhalation Counterlung

The original documents for unit certification dated April 1999.
Visit our website at www.eliteprodive.com for more Drager Dolphin information and training