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Inflating DSMB from QD hose

Discussion in 'Advanced Scuba Discussions' started by BlueTrin, Oct 26, 2020.

  1. NothingClever

    NothingClever Manta Ray

    # of Dives: 200 - 499
    Location: Red Sea and Atlantic Ocean
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    We keep saying ‘huge’ and other similar terms. I don’t consider a 6ft / 1.8m buoy to be huge but rather standard. I think those enormous ones from Highland and OMS at 10ft and 16ft fit that category.

    I shoot low (35-45m) here in the Red Sea not so much because of a teleporting drift like in the Florida Atlantic but simply to signal to the boat that I’m ending the dive and show him where I am. It’s about gaining his confidence. Our captains and DMs here are easily spooked or perplexed by anything outside the confines of an anchored dive, poodle jackets and 50 minutes.

    The duckbill DSMBs are OK but if not at full puff they can take on water if scootering.

    I’ve seen the regulator exhaust technique with the duckbill port but I don’t practice it enough to be good at it (my exhaust seems to run up the outside of the DSMB) so I just stick to oral inflation.

    Maybe I’m unskilled but the LPI method has always seemed like a bunch of faff.
     
  2. rjack321

    rjack321 ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Port Orchard, WA
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    On a genuinely deep CCR dive with 3 or more bailouts you might have quite a bit of gas in your wing to compensate for the weight of all that unused gas. But dumb to dump your wing in there as you're gonna be heavy and then need to hang on the bag. And all that faffing around makes for a shaky ascent. Although it is somewhat common to use the wing power inflator but hold down both buttons at the same time so the gas goes in the bag not the wing. I don't seem to have enough hands for this but some people like it. For me, it's easier to put a BC whip on a bailout and use a fully closed bag. The larger the SMB the deeper you need to shoot it, the really big bags have >50lbs of lift. That's 25+L of gas. Shooting that at 6m and you'll either have a barely filled bag or end up getting dragged to the surface. Shooting it from 5ATA that's 5L of gas, or 10lbs of lift. You can squirt in a tiny volume, check that everything is clear, then squirt the remaining 5L and release it without really moving.
     
  3. Snoweman

    Snoweman Great White

    # of Dives: 100 - 199
    Location: Atlanta, GA
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    Why? Wouldn't holding on to the line make up for the buoyancy loss?
     
  4. lsmike

    lsmike Angel Fish

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    I have this type of DSMB as well and it has the oral inflation valve, but with it being 2 meters (6.5 ft.) I take two or three full breaths to make it really stick out of the water.

    What my instructor taught me was to use the exhaled gas from my breathing regulator. Usually one or two exhales and it fills up nicely without extra work and because I'm exhaling I can manage buoyancy. Also I don't need to take the regulator out of my mouth.
     
  5. tursiops

    tursiops Marine Scientist and Master Instructor ScubaBoard Supporter

    # of Dives: 2,500 - 4,999
    Location: U.S. East Coast
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    Not while it is going up.
     
  6. lermontov

    lermontov Manta Ray

    # of Dives: 500 - 999
    Location: christchurch
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    Im assuming your on OC ?

    nothing wrong with a second LP hose on your stage - make it suitably long to work with. i normally dive with a ccr so i have an LPI on all my BO tanks so i have multiple options not just for my smb
    different scenarios involve different methods

    - coming up from a deep dive with a lot of deco ahead of you and a possible drift - make it a large smb , the wind may have picked up and now theres a bit of chop on the surface so youll want to be seen.
    Practice getting you smb out and ready before you reach your predetermined depth launch so the transition is only a few seconds rather then when you reach it then getting it ready, ive found using a LPI is best.

    diving in areas that have serious currents youll need to launch the smb at the same time as yours buddies- otherwise youll get split up and seconds do count -practice launching at the same time. Once you launch and the current catches it its like being on the end of a kite .

    practice practice practice
     
    Joris Vd, BlueTrin and NothingClever like this.
  7. Edward3c

    Edward3c Instructor, Scuba

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    If the DSMB has a Duck-bill valve it isn't open ended, but sealed. When using a Reg to fill one a large quantity of water is injected with the gas as it bobbles in. that's why I like the LP hose type. I can fill mine either way and occasionally practise using the Reg.

    Open ended DSMBs can have the gas pumped out of them by wave action, even when the end is weighted with lead or has magnets.
     
  8. hroark2112

    hroark2112 Tech Instructor

    # of Dives: 0 - 24
    Location: Raleigh, NC
    1,391
    1,431
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    I've done it from 60' and from 200'. Never had a problem.

    As far as why I have enough air in my wing....on my most recent OC dives I've intentionally had around 4 extra pounds of lead because I had a buddy who would whine about being too light/heavy/hot/cold/wet/whatever so I would either take some lead off of her or have extra to give to her. On CCR dives I usually have a little bit of air in my wing, sometimes more than a little on deep dives carrying extra bailout/deco gas.
     
  9. PfcAJ

    PfcAJ Orca

    # of Dives: 5,000 - ∞
    Location: St Petersburg, Fl
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    Nah bro. Shoot the big one.

    The little guys are harder to see and the longer it takes the boat to see you, the harder it is to find you.

    I use the wing inflator. If you want to use the drysuit one it might be best to just go vertical so you have enough slack to allow you to work the smb out in front of you.
     
  10. Diving Dubai

    Diving Dubai Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: Dubai UAE
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    The answer is always, use an AP Crack bottle dsmb. You'll never go back :)
     
    KenGordon and BlueTrin like this.

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