Drager Deco Fitting

[frogman-JCA]

Hi there,

As a recently converted rebreather diver who has completed the Drager rebreather course and purchased his new toy, I and thinking to extending my dive times and reducing my deco times by introducing a high O2 content mix into the loop. I understand the is a manufacturer who makes a adaptor which will allow a additional first stage to be connected to the dosage unit allowing the deco mix to be turned on for the stops and the bottom mix to be shut down, thus allowing a richer mix to flow into the loop. Does anyone know who can supply these fittings and do they have any contact details? Has anyone used one of these fitting and experienced any problems? I’ll welcome any advice from anyone who dives a rebreather

Regards
John

[divetheworld]

Originally Posted by frogman-JCA

Hi there,

As a recently converted rebreather diver who has completed the Drager rebreather course and purchased his new toy, I and thinking to extending my dive times and reducing my deco times by introducing a high O2 content mix into the loop. I understand the is a manufacturer who makes a adaptor which will allow a additional first stage to be connected to the dosage unit allowing the deco mix to be turned on for the stops and the bottom mix to be shut down, thus allowing a richer mix to flow into the loop. Does anyone know who can supply these fittings and do they have any contact details? Has anyone used one of these fitting and experienced any problems? I’ll welcome any advice from anyone who dives a rebreather

Regards
John

Tries to remember SCR.......

firstly the fitting, look here -> http://www.inspirationtraining.com/d...r_trainer.html

or here http://www.tecme.de/frame_eq1.htm

Highly reccomend the second link, nice guy called Martin.

The deco fitting plugs into the 60% or similar fitting which raises the FO2 in the loop, but too slowly (5.5ltr/min) to boost the loop FO2 nicely.
You need to tee it into the ADV aswell or have a manual add valve so you can flush the loop and raise that PPO2 quickly to make it worthwhile.
If you dont, you wont get past 60% FO2 before your deco is over and then what was the point of filling another cylinder with pure?
One of the problems with this is the pipe salad you will have if you dont do it properly, and the potential for feeding the wrong gas at depth by accident or by knocking the valve. Monumental screw up potential.

Having said this, my swagelok valve was removed this weekend for one reason or another and I flew my RB manually using a similar system directly off the knob. So it is possible.

I would suggest a 'Bob's bits' manifold or a Ray manifold connected through the supply gas. If you cant get one then go to http://www.tecme.de/frame_eq1.htm and get some 'tee' peices.

One last thing, very important.
If you shut down your bottom mix, and open your pure O2 without connecting to an ADV the loop will not replenish gas you blow off. So if you descend(not below the MOD of course!!) or clear your mask, your loop will not have sufficient gas for a lung cycle.
ADV is a must, bouyancy is a must, gas switching discipline is a must. If you plumb it right, its a peice of piss.
Other than that, its a cool way to learn your way to bridging the gap to CCR.

Hope that helps. Green button at the top right please!!!

[Andy]

hi

i converted my drager to run two mixes a little while ago to extend run times and shorten deco. I used 2 adv's and 2 first stages it may sound a bit over the top but its very easy to dive and works great

Andy

[divetheworld]

Originally Posted by Andy

hi

i converted my drager to run two mixes a little while ago to extend run times and shorten deco. I used 2 adv's and 2 first stages it may sound a bit over the top but its very easy to dive and works great

Andy

Setup right its a peice of piss is what I said, two ADV's sounds very easy.
Questions, is the lung limited in volume with all that gas addition hardware in the box?
And, why didnt you just go CCR back then?

[narked at 90]

hello brent Andy uses one of my oldsub frames which means you can hang larg tanks fit a nice wing and also set the lung volume to what you need he got over the problem of short hoses by fitting the tec-me angled hose extenders which has turned his unit into a nicly balanced rig, andy uses 7lt tanks rather than 3lt's both fitted with H valves and bailout regs.

it's a monster rig but he needs the gas because it's SCR but he doesnt have to carry staiges!

brent have you recived the AGA convertion i sent you?????
kind regards john routley

Originally Posted by divetheworld

Setup right its a peice of piss is what I said, two ADV's sounds very easy.
Questions, is the lung limited in volume with all that gas addition hardware in the box?
And, why didnt you just go CCR back then?

[divetheworld]

Originally Posted by narked at 90

hello brent Andy uses one of my oldsub frames which means you can hang larg tanks fit a nice wing and also set the lung volume to what you need he got over the problem of short hoses by fitting the tec-me angled hose extenders which has turned his unit into a nicly balanced rig, andy uses 7lt tanks rather than 3lt's both fitted with H valves and bailout regs.

it's a monster rig but he needs the gas because it's SCR but he doesnt have to carry staiges!

brent have you recived the AGA convertion i sent you?????
kind regards john routley

It does sound sweet, and simple too. I have two of the straight hose extenders, not quite right. I have to get round to cutting and turning them so I can put elbows on them to make them the same as your black ones. Wish I'd bought the angled ones now, they are cheaper too.
Bodged up a connection to try out the FFM and pulled the hoses a bit too hard and let some wet stuff in the loop. Not wise.

The reason is that I made a new backplate adaptor the other week and its moved everything so its not right again, woes of the homebuilder.

Memory like a seive lately too.

[Andy]

Hi Brent

i didnt go scr on this one as im currentyly converting an FGT to CCR should have it finished this weekend if swagelock do there stuff will post pics as soon as its done

Andy

[divetheworld]

Originally Posted by Andy

Hi Brent

i didnt go scr on this one as im currentyly converting an FGT to CCR should have it finished this weekend if swagelock do there stuff will post pics as soon as its done

Andy

Looking forward to seeing them Andy mate.
FGT looks a bomb proof peice of kit, scares small children and stuff huh?

I guess the info was no good for you Frogman?

Gee, no problem, your welcome.