Part 2 - Advanced DSMB Deployment Techniques

[BlueTrin]

Water temperature?

Are you scared of a free flow ?

 

[ginti]

Are you scared of a free flow ?

well, free flow is more of a problem for the second stage, isn't it? And, in any case, this thing will go to the surface once we deploy it, so it's a secondary issue.

But I wonder whether very cold water may in a way cause some problems.

 

[BlueTrin]

well, free flow is more of a problem for the second stage, isn't it? And, in any case, this thing will go to the surface once we deploy it, so it's a secondary issue.

But I wonder whether very cold water may in a way cause some problems.

I was wondering what kind of problems you were thinking of.

(And you are right about the free flow)

 

[ginti]

I was wondering what kind of problems you were thinking of.

(And you are right about the free flow)

I actually have no idea, this is why I asked I was more thinking that the valve could get stuck, but I am absolutely not sure...

Personally speaking, I wouldn't use that thing because I believe it would take a bit of space in my pockets; as a rule of thumb, the less stuff I have in my pockets, the better it is, for several reasons. But the idea is very nice, so I just want to be sure that it doesn't have any issue other than my subjective (and absolutely debatable) idea that I don't want to have extra stuff in my pockets.

 

[Wibble]

Crack bottle or CO2 SMB's are excellent as they're so so simple and fast to deploy. It's the pragmatic way to deploy a decent size bag to the surface.

The AP ones work very well and are popular in UK water (5C to 18C); on a boat there's nearly always one or more being used. The nice thing about them is you can open the valve a bit so it slowly inflates and is easy to control -- even stopping it from inflating if stuff gets tangled.

CO2 inflation's really simple but is a one-off; once the trigger's pulled the cartridge immediately inflates. From depth you can hold it without problems. Doesn't half accelerate as it gets bigger as the pressure reduces near the surface! Bigger SMBs use two 16g CO2 cartridges. They work really well and are very visible on the surface -- not flaccid unless they're holed.

Need to use a decent size reel with them all as it's much easier to wind up.

Pic shows a small 16gm CO2 SMB attached to a 100m/330ft reel.

 

[ginti]

Thaks @Wibble. Any disadvantage compared to an orally inflated system?

 

[Wibble]

Thaks @Wibble. Any disadvantage compared to an orally inflated system?

Ease of use. Speed. Convenience. Stand-alone inflation source. Not wasting bailout or diluent gas (if on CCR).

If you're orally inflating, you'll need a "few" lungfuls if you're using a decent sized SMB even from depth. Orally inflating if on CCR is just plain wrong and I'd argue is risky/dangerous -- you need some gas to clear the mouthpiece as you go back on the loop.

(I hate trying to inflate a bag by blowing into it -- more gas seems to come out of the sides and it's just bloody unpleasant. Far easier to use the drysuit inflation hose or the whip from the bailout.)

 

[ginti]

Ease of use. Speed. Convenience. Stand-alone inflation source. Not wasting bailout or diluent gas (if on CCR).

If you're orally inflating, you'll need a "few" lungfuls if you're using a decent sized SMB even from depth. Orally inflating if on CCR is just plain wrong and I'd argue is risky/dangerous -- you need some gas to clear the mouthpiece as you go back on the loop.

(I hate trying to inflate a bag by blowing into it -- more gas seems to come out of the sides and it's just bloody unpleasant. Far easier to use the drysuit inflation hose or the whip from the bailout.)

Ok, so the CO2 system has only advantages vs the orally inflating counterpart? Not even one disadvantage?

 

[rongoodman]

Ok, so the CO2 system has only advantages vs the orally inflating counterpart? Not even one disadvantage?

The obvious one that comes to mind is not being able to take them on a plane.

 

[BlueTrin]

Also I guess you should get the cylinder checked too?