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Trim is the Platform, Buoyancy the Heart and Propulsion the Art.

Discussion in 'Advanced Scuba Discussions' started by MichaelMc, Mar 27, 2020.

  1. MichaelMc

    MichaelMc Divemaster Candidate

    # of Dives: 100 - 199
    Location: Berkeley, CA
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    For this tread, we are assuming the points in RainPilot's link are right. Debating them is not this thread.

    Having said that, dive phases or activities may have various optimal orientations in the water. As aptly demonstrated by RainPilot above. Also an assumed bit for this thread. I should have mentioned it, earlier and forgot to. I'm glad he did.

    Also most rec divers are not really working on the bottom, just looking at it.
    So working divers trim needs are not this thread.

    (Skipping what might be useful at deco stops as tech is not this thread.)

    So, what fine points do you see in B/T/P for the focus of this thread.
    If there are none for you, not this thread.
     
  2. Colliam7

    Colliam7 Tech Instructor Staff Member

    # of Dives: 1,000 - 2,499
    Location: Kents Store, VA
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    Good point. I won't ask about 'why not'. :)
     
    MichaelMc likes this.
  3. mac64

    mac64 Barracuda

    # of Dives: 5,000 - ∞
    Location: Ireland
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    Leaving aside working or deco, a horizontal trim is a pain in the neck for a lot of divers, literally. Especially senior divers. So to put it forward as the perfect trim is wrong. It isn’t. It’s a perfect example of something been right on paper but terrible in practice.
     
  4. MichaelMc

    MichaelMc Divemaster Candidate

    # of Dives: 100 - 199
    Location: Berkeley, CA
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    Again, debating the premise is not this thread. Certainly if you spend much of your dive looking straight forward and have a stiff neck, horizontal orientation may not be for you, you may have to modify it slightly, to adapt to your dive. It is also not best suited to looking at walls. Or looking under ledges. The complexities that adds as a tradeoff to your dive are then unavoidable. They are covered in the link from RainPilot, and not this thread.
     
    Colliam7 likes this.
  5. mac64

    mac64 Barracuda

    # of Dives: 5,000 - ∞
    Location: Ireland
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    I’m that case Trim ( whether it be vertical or horizontal) is the platform
    Buoyancy (whether it be neutral, negative or positive) is the heart and
    Propulsion (whether it be physical or mechanical) is the art because where diving is concerned they’re all relevant
     
    MichaelMc likes this.
  6. CuriousRambler

    CuriousRambler Solo Diver

    # of Dives: 25 - 49
    Location: California
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    It seems like you're asking for the impossible @MichaelMc - it's just not within the bounds of SB to not debate the opposing side of anything that's posted :banghead:. In my experience, the more you try to guide a thread, the more people are just going to do the opposite to convince you you're wrong, and ignore what you might have hoped to get out of the thread. After all, this is *their* thread :p

    To the topic: I'm a pretty inexperienced diver, but have always been very skills-focused. I'd rather spend my "young" dives refining my control and comfort, than chasing animals or trying to snag photos. Once I'm comfortable and competent underwater, I figure I'll be better-able to enjoy the dives where I want to see things. Obviously there's a balance here, I'm not going into the water for regimented rehearsals - if I didn't enjoy my diving, I'd quit. But I quickly tire of chasing insta-buddies who want to do an underwater 10k against the current, because they heard there's something cool on that compass heading.

    But I digress.

    Taking things out of order: I feel like my buoyancy is pretty decent. From OW, through AOW, and later dives with much more experienced buddies than myself, I've managed to garner compliments on my buoyancy. I'm certainly not saying it's perfect, but I kind of "get it," and it's always felt very intuitive to me. As I dive more, I realize I definitely rely too heavily on my breathing to keep me "on target," but that also gets corrected fairly rapidly on the dive. One of my biggest challenges, going back to chasing my buddies, is that I find it difficult to accurately gauge my buoyancy while moving, for all the reasons previously mentioned by others. This segues into trim pretty well;

    My trim is decent, at best. I try to maintain horizontal, and feel like I do pretty well most of the time. I've got a decent handful of candid photos snapped by buddies across multiple dives where I'm in nearly textbook horizontal trim. But honestly, I think they're more of a fluke than reality. I've been fiddling with weight placement, and changed amounts of weight, shifted between top and bottom cambands, etc. in the last several dives. I'm at a point where I feel decently in-trim most of the time, but occasionally take a slow tumble forward or backwards while resting stationary. Probably 70% of the time, if I quit swimming and try to just hang near a reef, it works as expected. The other 30% of the time, I'll slowly drift forward, or start tumbling forward or backward. Still not sure what's causing any of those, except to blame trim, and probably the amount of gas in the tank at any given time.

    Propulsion is another thing I'm working on. My frog kick is good enough to move me around the reefs and wrecks and check things out, but I wouldn't call it powerful. Helicopter turns are simple and intuitive for me, and just kind of happen as needed, without much thought. Back kick? Hopeless. Absolutely hopeless.

    I feel like I'm running up against two distinct problems with progressing and improving my skills underwater.

    First is buddy selection. I wouldn't really complain about anyone I've dove with recently, but their focuses are not aligned with mine, and almost every recent dive I've done has been "let's cover a lot of ground fast!" which isn't really conducive to practicing trim, buoyancy, or propulsion techniques (other than "flutter hard and fast, because that's what everyone else is doing!") I haven't actively dove in about a decade, and am really just trying to get back into it. I'm just happy to be in the water for now. But going forward, I expect I'll need to find a like-minded buddy to pair up with. Hopefully one who can provide constructive feedback about my diving, but definitely someone who's on board with a slightly slower pace and a little bit of practice.

    Second, and probably the bigger thing at this point: it's difficult to self-assess these skills. Propulsion probably least so, as you can pretty easily tell bad results from good. Even there though, I suspect a knowledgeable "coach" could quickly improve just about any 'self-taught' diver's technique. That's doubly true for trim and buoyancy. What "feels" right to me, could be a horrible habit that might prove difficult to break down the road. That line quickly tips into debate territory - if it feels right to me, who is the next guy to tell me it's wrong? If it works, it works. But dodging that debate, and sticking within the premise of the thread - how does one recognize a plateau, or how does one improve without external input? I don't think a "Peak Performance Buoyancy" card in my wallet will necessarily make an ounce of difference, where a knowledgeable buddy could "unofficially" revolutionize my diving. It just comes down to getting in the water with the right person, but do you find that person through a training agency, putting a personal ad in your local newspaper, or just swimming blindly until you bump into them?
     
    MichaelMc likes this.
  7. EFX

    EFX Solo Diver

    # of Dives: 200 - 499
    Location: North Central Florida
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    I had the same problem with the "tumbling". It was more pronounced when I was hanging vertically during a safety stop. Sometimes I would pitch forward and would have to struggle to stay upright. I discovered the problem to be the integrated weights inside my weight pockets on my BCD (I used a Scubapro Nighthawk at the time) had shifted to the front of the pockets when I was swimming horizontally. Then, going upright, the weights would still be toward the front shifting my center of gravity to the front causing me to pitch forward. I had to lean back to shift the weights backward in the weight pockets which enabled me to remain upright.
     
    MichaelMc likes this.
  8. MichaelMc

    MichaelMc Divemaster Candidate

    # of Dives: 100 - 199
    Location: Berkeley, CA
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    With the resting frog kick position, your fins/legs being a bit negative helps with not tumbling forward/backward when still. They are a bit of weight that you can move forward or backward by bending or extending your knee a bit. Bending or extending your knee to the point that will hold you steady becomes fairly instinctive. If gear or weights are shifting like EFX mentions, that would make it much harder.

    To me, the other challenge is that if you have a lot of weight above you, from a negative tank or lots of cam band weight, you may be unstable. As your center of mass, shifted by that lead or tank, is above your center of volume/buoyancy, which is mostly your body. So I try to watch my front/back mass distribution. An aluminum tank makes that easier, HP tanks harder.
     
  9. CuriousRambler

    CuriousRambler Solo Diver

    # of Dives: 25 - 49
    Location: California
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    Good points! Most of my past diving has been Jet fins. Getting back into it, I picked up some Scubapro Go Sports, because I'm trying to squeeze in dives after work on a business trip, and didn't fancy lugging the Jet weight around in my luggage. The fins are definitely positively buoyant, then add in some 5mm booties. I've absolutely noticed the floaty feet a couple of times, but didn't connect those dots somehow :facepalm:

    Weight distribution could also be a factor for sure. I've kind of played with intentionally rolling one way and another to see if it feels like I'm "top heavy" while horizontal, but I don't really think that's the issue with my current setup: SS BP/W, 2x 3lb weights (too much, but the smallest weights I have access to for this trip..I'm confident 4lb will be plenty, possibly even less) on my bottom camband, Al80. Swim trunks, long sleeve rash guard and some 5mm booties kind of simplify the depth compression factor.

    The fun part is going to be going back to California, jumping in my 7mm suit, and starting all the problem solving over again! :rofl3:

    Edit: weight's on my bottom camband, I mistakenly said top.
     
  10. MichaelMc

    MichaelMc Divemaster Candidate

    # of Dives: 100 - 199
    Location: Berkeley, CA
    1,679
    963
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    Positive feet also works, just it changes the direction you shift them. Just absolutely neutral lower legs/feet/fins does not help much.
     
    CuriousRambler likes this.

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