• Welcome to ScubaBoard


  1. Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

    Benefits of registering include

    • Ability to post and comment on topics and discussions.
    • A Free photo gallery to share your dive photos with the world.
    • You can make this box go away

    Joining is quick and easy. Login or Register now by clicking on the button

SMB spool length recommendations

Discussion in 'Lift Bags, SMBs and Reels' started by Dogbowl, Mar 20, 2018.

  1. Zef

    Zef Divemaster

    1,108
    609
    113
    only thing I would change from what tbone states is to deploy from 30-35 ft instead of 20ft....change in buoyancy will be a little more stable as you shift slightly up or down in the water column while sorting out and deploying the DSMB. There will be a greater swing as you shift from 20ft especially if you move upwards.

    -Z
     
    Dogbowl likes this.
  2. RyanT

    RyanT Solo Diver

    # of Dives: 500 - 999
    Location: Maryland
    1,584
    1,198
    113
    If there is any current, the sooner you shoot your bag the better. Consider for example, doing a wreck dive at 100' with a decent amount of current. If you start a free ascent and then wait to shoot your bag at 20-30' you can be well off the wreck before you alert the boat to your whereabouts. On the other hand, if you shoot your bag immediately as you begin your ascent, your bag will surface closer to the boat and the crew can monitor your whereabouts. And it's way easier to shoot a bag from deeper compared to 20'.
     
    KenGordon and Dogbowl like this.
  3. uncfnp

    uncfnp Solo Diver

    # of Dives: 500 - 999
    Location: North Carolina
    5,609
    3,721
    113
    Ok. Lots of good info but thinking specifically of Coz.

    First, I would personally go with the larger. The increase in size and weight is minimal and gives you more line should you need it.

    Second, I deploy at depth when I am ready to ascend. It is so much easier to maintain a stable depth with the reef or bottom as a frame of reference and small changes have less effect then depth changes at the safety stop. This is especially important when you are just learning the skill.
    Inflating the bag is so much easier as well. It takes less effort to inflate the bag at depth since the size will automatically increase as the bag rises.

    And since it is Cozumel, the average depth at the end of a dive is going to be at are less than 50. But should a dive go south early and deeper, you will have the line.

    Edit: out of curiosity I when back and checked my dives from the last trip. Out of 22 dives only 4 had depths below 50 when I shot a bag and started up. Of those four, only one was below 60.
     
    Last edited: Mar 20, 2018
    Dogbowl likes this.
  4. Dogbowl

    Dogbowl Loggerhead Turtle

    # of Dives: None - Not Certified
    Location: Somewhere
    2,479
    1,546
    113
    I guess there’s really no right answer! :wink:
     
    Lorenzoid, Bierstadt and uncfnp like this.
  5. Bierstadt

    Bierstadt Barracuda

    # of Dives: 50 - 99
    Location: Erie, PA
    294
    197
    43
    I am with you on being a bit confused on the best use of reels and spools. I bought some cheap ones from Piranha to mess around with this summer and gain some experience. Nothing wrong with having a toolkit of line handling devices, and plastic spools are cheap.
     
    Dogbowl likes this.
  6. Jack Hammer

    Jack Hammer Solo Diver

    1,608
    912
    113
    Actually I think you'll find that there are several "right" answers... the trick is to understand which one applies to which dive and conditions you are making.

    Generally I find a 100' spool adequate for most recreational dives, 150' is nice if I'm on the deeper end of that, a longer reel for technical dives.
     
    Dogbowl and Bierstadt like this.
  7. Bierstadt

    Bierstadt Barracuda

    # of Dives: 50 - 99
    Location: Erie, PA
    294
    197
    43
    @Dogbowl sounds like we are in a similar spot. I am planning to try out a DGX mesh buttplate bag to hold my dsmb and 60' spool or 150' spool or 150' reel or 250' reel, for what it is worth. If I don't like that I'll try using a pocket or a bungee to my backplate. Post what you decide to try.
     
    Dogbowl likes this.
  8. Lorenzoid

    Lorenzoid idling in neutral buoyancy Staff Member

    # of Dives: 200 - 499
    Location: Atlanta, USA
    8,334
    4,783
    113
    Exactly. I'm willing to bet that divers who do a variety of kinds of diving own a variety of spools (and maybe even SMBs in more than one length). If you're doing wrecks or otherwise deep dives, take a larger spool, or a reel. If you're being led around by a DM in Cozumel on the sites dive ops take the average diver to, you may rarely need to shoot an SMB at all, and if you do, you could almost always ascend to 20 feet and shoot it there without being swept away from the boat. (At worst, another boat finds you--you will not end up out at sea.) If you're doing advanced sites in Cozumel--something I haven't done--then take a larger spool. The average vacation diver doesn't know how or doesn't feel confident shooting an SMB, and the dive ops are well aware of that. The last liveaboard I took recommended divers carry an SMB with 20-30 feet of line attached. I have also seen leashes advertised that I assume are similarly intended to be deployed at safety stop depth. It's great that we on SB are among those who find shooting an SMB from significant depth to be an important skill, but I would try to keep in mind that it's not really expected or necessary for the vast majority of "vacation diving." I don't use the term "vacation diving" in a disparaging way--it's mostly what I do, because I really love it. I summary, I think a "small" spool with 100 feet of line should cover most of us vacation divers in the most likely scenarios.

    I noticed Light Monkey has a "mini" spool with 25 feet of line. That could be just the ticket for some of the lazy vacation diving I do. Cozumel--I might want more than that due to the likelihood of current. Just sayin'.

    @uncfnp , what op are you diving with that you find yourself shooting an SMB so often? I don't think I have ever seen another diver shoot an SMB in Coz, though many of us carry them just in case, and of course there are people on SB who will tell you they have "needed" to shoot one in Coz on average every so-many dives. If you're doing it just for practice, with an op that is okay with that, then I suppose that makes sense. I have been under the impression that most ops would rather divers not deploy SMBs because it could become confusing.
     
    Dogbowl likes this.
  9. uncfnp

    uncfnp Solo Diver

    # of Dives: 500 - 999
    Location: North Carolina
    5,609
    3,721
    113
    One reason you do not see many is because Aldora’s policy is for all divers to ascend together. I dive 3Ps and they allow divers to dive their gas/computer so Eric and I rarely ascend with the DM and with the boat traffic in Coz I am not going up without my own SMB on the surface. Even if the DM is only a short distance away, if he is not going up at the same time I will shoot my own. Currents can change with depth and I have no desire a surface away from the DMs bag.

    I can understand why Coz Captains would prefer most divers not to shoot a bag. It could get very confusing on the surface when its a popular dive site with a lot of boats on the water. I have mine uniquely marked to try and help my boat know its me.
     
    Lorenzoid and Dogbowl like this.
  10. Zef

    Zef Divemaster

    1,108
    609
    113
    Reading some of the posts it would seem that there is a suggestion that diving with a "larger" spool is some how burdensome. I would contend that the difference between a spool with 25 feet of line is not much different than a spool with 150 feet of line. The real difference is that if you drop the spool and or mis-manage how much line you have payed out things can become quite a tangle and pain to re-roll....but that is true regardless of how much line/how big the spool you are carrying....its just the magnitude of the mess that may change.

    It is correct that depending on the the type of diving, a diver may choose to carry different spools.....a diver may carry multiple spools when cave diving or penetrating a wreck as an example. But for non-overhead environments where a diver is just carrying a DSMB and a spool, I would wager that, on average, most divers either have 1 spool that they reach for consistently.

    It makes no sense, to me at least, to limit yourself to 25 ft of line when carrying 3 times that is negligible in weight and space both in a suitcase or as part of one's rig.

    10 to 15 dollars will get you a plastic spool, 50 meters of line, and a double ender bolt snap. That is fairly inexpensive in the unlucky event that you drop the spool or it inadvertently unclips from your d-ring and can't be recovered or found.

    Deploying a DSMB and managing the line payed out is a perishable skill so practice often. If you are diving on vacation where the guide usually shoots a marker for the group there is nothing wrong with letting the guide, DM, captain know that you want to/will be practicing deploying your own. When the guide shoots their's, separate yourself a bit from his/her position and pull yours out and send it up. I have never been on a dive where the boat complained that they were confused because too many DSMBs were launched.

    Don't sweat this too much. Buy a spool with 100 to 150 feet of line (or however much you think is practical) and start working on perfecting your deployment and management of your DSMB....this last part is what is important regardless of what how much line is on your spool or from what depth you launch from.

    Here are the important factors to keep in mind:
    1. Buoyancy control
    2. task management during setup
    3. Buoyancy control
    4. deployment of DSMB
    5. buoyancy control
    6. ascent and line management
    7. Oh yeah, don't forget buoyancy control

    -Z
     

Share This Page