Deploying DSMB using Finger Spool

https://youtu.be/DXECkJcLGT4

DSMB is a marker to show that there is a diver nearby. 

1. It is most useful for searching a lost diver.

2. It stops boats from going near this place and injure divers with their propellers.

3. It is an additional floatation device.

I first thought of DSMB when I was thinking of diving without any floatation device or the BCD because they are too expensive and may not be necessary when we dive shallowly, less than 4 m allowed by the 100 % oxygen tank. 

However, it is dangerous because we can get tired tring to breath when we are not floating enough especially in a rough sea. Aluminium tanks when empty provide some floatation but our extra weights make us heavier. In an emergency we may need to remove all the weights. Still, extra bouyancy provided by the DSMB will help a lot.

There are many divers hurt in Sabah caused by boats getting near divers with many more near misses. I am surprised that DSMB is not taught in diving lessons and instructors do not deploy any marker bouy near the diving site.

Tieing Finger Spool to DSMB

https://youtu.be/4MqPNJA6eRs

Tieing Finger Spools

https://youtu.be/srNkfEvorM8

Scuba Cylinder Valves

https://en.wikipedia.org/wiki/Scuba_cylinder_valve

Go to the Structure of the valve to get a more complete specification.

Once you get the specifations, you should notice theat these Scuba connectors are similar to Medical tanks and PCP Air guns and Paint Ball guns.

The cylinder threads where the tank valve is to be attached is of M25x2 for ISO standard. 25 means its diameter is 24 mm. 2 could be the pitch specification.

Unfortunately there are also BSA tanks using the 3/4 x14, the 3/4 is the diameter in inch, and 14 specifies the pitch.

Smaller tanks use the ISO M18X1.5 thread. The 1L Smaco or Dedepu tanks use this thread.

To insert gas i to the cylinder, you use another connector. The female part is usually the DIN G5/8 connector. It is a screw-in type. Medical oxygen tank also use this connector. But Scuba also uses the Yoke type for pressures less than 200 bar or 3500 psi.

The Dedepu 1L tank uses another connector commonly used in PCP Air guns also, called 8mm connector. 

Scuba DIN vs Yoke Connectors

DIN connector is compulsory above 3500 psi.

Most DIN heads are provided with Yoke converter which can be removed with an allen key. It is called converter valve.

https://youtu.be/1uvOK6mUxlU

Shallow Dives are Much Better

https://youtu.be/8XVcxFcFFp8

Shore Diving

https://youtu.be/_6vJQgD-idk