SMB use

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Kevin

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Blackburn, England
Can anyone tell me what the 'proper text book way' of coming to the surface after deploying a SMB is?
An instructor at my local shop has said that it should be deployed from about 10m and the line wound back onto the reel as ascending.
If this is the correct way, how do you control your ascent rate?
 
Kevin,

That is correct - yesterday we shot a bag from 90 feet (30M) - ascended to 70 and stopped for 3 minutes, then we ascented 10 feet with a minute stop at each 10 foot level.
All while reeling in the line to the spool.
How do you control your ascent rate? You just make sure you are neutrally buoyant at the stops - then you just hang there and let time pass.
If you want to do something like that I suggest you start with just practising being neutral in 20 fee and hovering 5-6 feet of the bottom, then ascent 10 feet and stop again...

big T
 
If everything is setup properly after the deployment, you can even make yourself very slightly negative and clip the reel to a d-ring. As long as the "lock" (usualy a twist knob or wing-nut type thing) is tightened, you can just "hang".

If you have a "center" d-ring for scootering, that seems to be the most popular clip off spot for this. It lets you sort of "sit" in the water and relax. Well... As long as the surface is calm. :wink:
 
Ok - now that is something I would NOT recommend you EVER do - think about it - you have 60 feet of line out - you have no clue what could pass you - do you REALLY want to be clipped of to that???
Besides - youe buoyancy skills surely should be so that you can stay neutral at any placce in the water column - also remember that you are only stopping for 1 minute in most locations - that would be an awful lot of clipping and unclipping - not to mention the hazards of getting yourself entangled...

Fold your arms and let the spool float in front of your face - that is your visual reference point for depth and it will keep it from drifting away.

Anyway - I guess I'm too busy diving to come up with great ideas.

Big T
 
Originally posted by WetDane
Ok - now that is something I would NOT recommend you EVER do - think about it - you have 60 feet of line out - you have no clue what could pass you - do you REALLY want to be clipped of to that???

Fold your arms and let the spool float in front of your face - that is your visual reference point for depth and it will keep it from drifting away.

Big T

You know, I hadn't thought of that. I had a Decompression Procedures instructor tell me about 'sitting' on the reel... He said it was done all the time. Go figure.

I did it once or twice during the course while we were practicing drift deco. We've always had an anchor line or something "solid" to hang from for dives since.

Thanks to your words of wisdome above, I don't plan on doing it again.

The heads up is appreciated. :)
 
dc4bs,

Don't clip the reel to you. In fact, don't use a reel for this at all. Use a spool and a double-ended barrel snap.

The spool should be rewound as you ascend.

- Warren
 
Glad you guys got in with the anti-clipping on advice - I was with someone last month when they deployed their SMB for the first time. Having just watched me let go because I had a tangle they decided to clip on and send it up. They got away with it that time and I told him it was a bad idea - the next attempt he had a tangle and let go, very glad he was not clipped on....

I must try and work out the method for using two reels in serial so if the first snags you can use the second. Anyone got any advice on that one?

Jonathan
 
Craig,
I'm just happy that you see my logic.

As far as using two reels?
Hmm - I think I would pass on that one - for one thing - I only use the reel to lay line, not to shoot a bag - for that I use a delrin spool liek the ones Halcyon makes. The advantage of the spool over the reel is that there is no handle or feeder for the line to get tangled in - you just hold the spool between two fingers as the bag goes up - when the bag is up the spool with stop running and you can use the double ender to clip the line to the spool securing it from running out any further.

That's pretty much it - wind the line back in as you ascent.

Big T
 
Hi there,

I think Kevin has been taught to deploy the SMB from mid water, I have seen this done and it can be good.

Instead of shooting the bag up from the bottom and winding in 20, 30, or more metres of line, ascend free to about 10m (still well below any boat traffic you will meet - anything larger and (a)you shouldn't be diving there and (b) anything that big wouldn't see you, or be able to avoid you.

This saves winding in lots of line and messing about with reels all the way up. It does however require a bit more skill in deploying the SMB and being neutrally buoyant doing it.

One good tip is to dump your buoyancy air into the bag from your BCD - you and the bag still retain the same buoyancy so no one sinks and no one rises. you can let the bag up (it will expand and rise quicker so still no clipping on) while you hold onto it. Once it is on the surface, you can re-inflate the BC or drysuit and regain neutral buoyancy independently from the SMB.

Not a trick for beginners, but if you are using a little reel (I do, for easier storage) then it saves a whole lot of winding.

Ascent can still be controlled by watching your timepiece and depth gauge , or just the computer ascent rate indicator (easier).

Safe diving,

Will
 
Originally posted by willuns
Instead of shooting the bag up from the bottom and winding in 20, 30, or more metres of line, ascend free to about 10m

One good tip is to dump your buoyancy air into the bag from your BCD - you and the bag still retain the same buoyancy so no one sinks and no one rises.

Ascent can still be controlled by watching your timepiece and depth gauge , or just the computer ascent rate indicator (easier).

Will

Hey Will,
I think you missed one point - the deep bags are used for deco stops - we start at 90 feet (30M), ascent to 70 (where the bag is shot and gas switch is done), from there on wee go 10 feet at a time for 1 minute - this is why we use the bag in the first place - to have the visual depth reference.

Although I have never done it - i do not like the idea of dumping from my BC - since a lot of gas is going to leak because I can't get a good seal from a power inflator - I doubt that you would maintain the same buoyancy, I use the dry suit inflator, the quick connect does not attach, it just blows gas when pushed on, you only need very little gas in the bag anyway.

Ascent can be controlled with depth gauge and time piece - but the whole point of the bag is to have a visual reference as it is going to tell you if you are going somewhere much faster than your computer... And it is nice for your pcik up to have an idea where to go look for you - since the deco coming up is a 10 minute affair - there are a lot of places here where you can go a long way in 10 minutes...

Big T
 
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