ex. Dräger Travox 120

I got a Draeger Travox 120 and modified it into a "river diving" rebreather.

MeTravox_00.jpg
MeTravox_00.jpg

It needed some modifications to become a safe manual mode CCR

The original Draeger Travox 120 is a fire fighter device. Exhale is going directly into the scrubber. Also the direction valves are far away from the mouthpiece.
And there is no mouthpiece but a mask. As the mask has a rounded pane, its working like a lenses, making it unsuitable for use in water.
Without mouthpiece, there is no closing valve. The device originally works with pure oxygen, with a fixed flow of 1.5 liters/min.

First tests, with only small modifications.
MeTravox_U_2.jpg
MeTravox_U_2_t.jpg
MeTravox_U_3.jpg
MeTravox_U_3_t.jpg
MeTravox_U_4.jpg
MeTravox_U_4_t.jpg


The way it looks today.

I reversed the breathing loop direction. That way, exhales go directly into the counterlung, with also works as a water trap for quite a large amount of water.
I took out the old direction valves and made some new housings, placing the new valves in the new mouthpiece.
For less water current resistance, the tubes are only placed asymetrically on the left side, nearer to the mouthpiece center than in normal configs.
Lastly a smale 1 liter steel bootle as diluent and some holes to avoid bubbles collection in the case completes the CCR modifications.

MeTravox_A_00.jpg
MeTravox_A_00_t.jpg
MeTravox_A_01.jpg
MeTravox_A_01_t.jpg
MeTravox_A_02.jpg
MeTravox_A_02_t.jpg
MeTravox_A_03.jpg
MeTravox_A_03_t.jpg
MeTravox_A_04.jpg
MeTravox_A_04_t.jpg
MeTravox_A_05.jpg
MeTravox_A_05_t.jpg
MeTravox_A_06.jpg
MeTravox_A_06_t.jpg
MeTravox_A_09.jpg
MeTravox_A_09_t.jpg
MeTravox_A_07.jpg
MeTravox_A_07_t.jpg
MeTravox_A_08.jpg
MeTravox_A_08_t.jpg
MeTravox_A_11.jpg
MeTravox_A_11_t.jpg
MeTravox_A_12.jpg
MeTravox_A_12_t.jpg
MeTravox_A_13.jpg
MeTravox_A_13_t.jpg
MeTravox_A_14.jpg
MeTravox_A_14_t.jpg
MeTravox_A_15.jpg
MeTravox_A_15_t.jpg

 

Mouthpiece modifications

Based on Draeger Ray flapper valves I turned two housings and connected them between the tubes and the original mask connector.
Mouthpiece is a military version that can be closed as usual and is connected only on the left side.
Instead of two tubes over the shoulder the two original tubes "hang down". In stronger currents causes less annoying flutter.
MeTravox_M_2.jpg
MeTravox_M_2_t.jpg
MeTravox_M_3.jpg
MeTravox_M_3_t.jpg
MeTravox_M_4.jpg
MeTravox_M_4_t.jpg
MeTravox_M_6.jpg
MeTravox_M_6_t.jpg
MeTravox_M_7.jpg
MeTravox_M_7_t.jpg
MeTravox_M_8.jpg
MeTravox_M_8_t.jpg
MeTravox_M_1.jpg
MeTravox_M_1_t.jpg


ADV valve modifications

. The 2.stage is now connected to switchable diluent.
Additional push buttion alows manual diluent injection .
The inhale vale is changed to work at a higher suction by a stronger spring.
The original overpressure valve is not good for underwater usage. It's closed by a screwed plate.
MeTravox_A_06.jpg
MeTravox_A_06_t.jpg
MeTravox_A_14.jpg
MeTravox_A_14_t.jpg
MeTravox_V_1.jpg
MeTravox_V_1_t.jpg
MeTravox_V_2.jpg
MeTravox_V_2_t.jpg
MeTravox_V_3.jpg
MeTravox_V_3_t.jpg


Overpressure valve and sensor box

The snot locker box is moved from the tube to the exit of the sorb housing and a modified Apeks valve is fitted.
The valve must be modified to have less leakage after strong ventilations. In the same box there is place for the O2 sensor.
MeTravox_O_1.jpg
MeTravox_O_1_t.jpg
MeTravox_O_2.jpg
MeTravox_O_2_t.jpg
MeTravox_O_3.jpg
MeTravox_O_3_t.jpg
MeTravox_O_4.jpg
MeTravox_O_4_t.jpg



Modifications of a second Travox

Learning by the expiriences of mine, here are some enhancements we made for a good friend.

Direction valves

Much better solution of the valves, includet directly in the tubes.
MeTravox_II_01.jpg
MeTravox_II_01_t.jpg
MeTravox_II_02.jpg
MeTravox_II_02_t.jpg
MeTravox_II_03.jpg
MeTravox_II_03_t.jpg


Sensor and overpressure valve

The OVP is a safety valve, in case O2 source is not closed and mouthpiece is closed.
My newest design incorporates that functionality with the O2 sensor housung. The housing is fixed in the counterlung via normal p-connector.
MeTravox_II_04.jpg
MeTravox_II_04_t.jpg
MeTravox_II_05.jpg
MeTravox_II_05_t.jpg
MeTravox_II_06.jpg
MeTravox_II_06_t.jpg


ADV

The ADV has a connction to a normal inflator nipple. That way it's easy to use a stage as diluent.
MeTravox_II_07.jpg
MeTravox_II_07_t.jpg
MeTravox_II_08.jpg
MeTravox_II_08_t.jpg
MeTravox_II_09.jpg
MeTravox_II_09_t.jpg


Divers

Some snapshots of minor details.
MeTravox_II_10.jpg
MeTravox_II_10_t.jpg



TypeModified Draeger Travox 120 -> mCCR
Size 550 x 400 x 210 mm
Weight empty 13 kg --> full equipped 18 kg
Jacket None
Breathing bag volume > 7 liter
Scrubber 2.4 Kg Dive Sorb
Bypass Modified Draeger Travox
Over pressure valve Modified APEKS
Breathing hose Modified Draeger Travox
Diluent tank 1 liter  steel
Regulator Diluent Alysee, modified
O2 tank 1 liter  steel
Regulator O2 Draeger travox
O2 gauge computer HS Explorer or Air-Z O2, MeOxy, ...
Dosage constant Draeger travox 0.8 l/min
Dosage manual injection O2 and diluent
Specialties Light, easy diving device.
Goals: 20m depth, max 2.5m/sec current.   
5 minutes cleaning / preparation.
 



Idea of an alternative mouthpiece

MeTravox_MP_01.jpg
MeTravox Mouthpiece variant

3D CAD of alternative mouthpiece