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Evolution of my Dive Rig

Discussion in 'Hogarthian Diving' started by DiveDaddyDale, Oct 8, 2013.

  1. DiveDaddyDale

    DiveDaddyDale Divemaster Candidate

    # of Dives: 100 - 199
    Location: Plano Texas
    44
    3
    0
    When I began diving I initially used the ST vest-style BCD set up (I think mine was a Mares one week and a Zeagle the next. For a while, I rented this gear each weekend and got about 12 dives completed. By the 10th dive I knew I was going to want to continue improving my skills and venturing into more advanced diving so I began shopping for my 1st rig.

    A good man at ST directed me to look into the bp/w type dive system and I began reading the forums extensively. I learned that bp/w was the way to go if I wanted to progress beyond basic diving and furthermore I learned that I liked the DIR concept of HOG rigging. On the advice of many forum posters I chose to go with the DSS steel bp. I also bought an 18lb Oxycheq wind and mounted it w/o an STA.

    My initial mistake was to not take into consideration what tanks I was using and what tanks I might like to use. My initial test dive (pool) using my AL80 was OK although I had some difficulty with holding consistent depth. I went to the lake that weekend and my 1st dive using the AL80 was cool so I though everything was OK. For my second dive, I hooked up the steel 100 and stepped off the bottom stair at CSSP and, to my surprise, went straight down 10' even with the wing halfway inflated. I blew gas into the wing and by heavy finning I was able to surface but could not get "floaty".

    Oops, mistake 2, not entering the water much more carefully, good thing the bottom was only 8-10'.

    Back to the drawing board. I switched the 6lb steel bp for the 2lb Kydax plate and the 18lb wing for a Hollis 25lb wing and then tried the dives again. Wow, and not in a good way! Something about the physics of that particular plate did not match with the physics of my body and I bounced up and down like a yo-yo unable to hold any sort of reasonable buoyancy. Back to the drawing board, I put the steel plate back on and did a lot more research while just using my steel plate, AL80 and the 25lb wing. During this time I also discovered that not only was I too negatively buoyant but I was also diving an unbalanced rig as I could not swim it up from the bottom with no lift in the wing.

    I ran numbers, guessed some estimates and calculated that my rig weight was 14lbs and my dry weight going into the water (minus my body weight) was 32lbs. Although I have read many posts from forum divers that they dive this same rig and have to use weights, I have no weights at all and still am heavy. Honestly I don't see how anyone could swim up a 35lb weight...?

    My latest evolution is that I have found a set-up that uses an aluminum plate a 30lb wing and minimizes any extraneous weight. This set up weighs in at 7lbs. This reduces rig weight by half to 7lbs. I have also taken some other measures like switching to OMS Slipstream fins which are almost neutrally buoyant, ditched my snorkel, taken off 2 D rings, changing to a neutrally buoyant mask and removed the plate pad and shoulder straps. Will this work? I will post back after my test dives.
     
  2. Jim Lapenta

    Jim Lapenta Dive Shop

    # of Dives: 500 - 999
    Location: Canonsburg, Pa
    16,879
    8,582
    113
    you sound like you need to stop experimenting and get with an instructor or mentor who knows what they are doing. This is a grenade approach to a job that requires a sniper rifle. remove 2 d rings and neutrally buoyant mask (never heard of that)?
     
    ErikNYC, BAMA6977 and FM1520 like this.
  3. Dr. Lecter

    Dr. Lecter Solo Diver

    # of Dives: 500 - 999
    Location: NYC/Honolulu
    4,139
    2,923
    113
    From what you've described, I don't think the buoyancy issues are 100% related to the rig.

    Another thing: how much ballast are you adding? Swimming up a full steel 100 with a 6lb SS plate shouldn't be a problem, much less with ~10lbs of lift in the wing, so you must be wearing a :censored:ton of lead somewhere.
     
  4. FM1520

    FM1520 DIR Practitioner

    # of Dives: I just don't log dives
    Location: Coronado, CA
    428
    119
    43
    you've got to be kidding. You have no idea what you are doing and what you are trying to do is not that hard.
     
  5. DiveDaddyDale

    DiveDaddyDale Divemaster Candidate

    # of Dives: 100 - 199
    Location: Plano Texas
    44
    3
    0
    I believe I mentioned that I am wearing no weight at all. I think it is an error to state that I am swimming up 6lbs of plate. The entire rig weight, plate and wing, equipment and all must be taken into account.

    In addition masks, fins, D rings, SMBs and all other items have weight and are either positive, neutral or negatively buoyant. And I can show you a mask that weights in at 18oz verses a mask that weights 6oz. A half pound difference here and there and I end up with a rig at half the weight of what I started with.

    Just because an individual has "never heard of such a thing" does not make that thing any less of a thing (LOL).

    The eh point about an instructor is well taken and indeed I am pursuing that path also.
     
  6. ams511

    ams511 Solo Diver

    # of Dives: I just don't log dives
    Location: Miami, Florida
    7,200
    1,994
    113
    I am amazed you you have that much equipment lying around to use for testing. I thought I was the only one with such a collection.

    What are you using for exposure protection? and how deep are you doing the testing?

    BTW, weight on dry land is meaningless, what matters is the buoyancy in the water. An 18 OZ high volume mask could well be more buoyant than a 6 OZ low volume mask because of the difference in displacement.

    One of my pet peeves is people saying "steel 100s", please tell us exactly what tank you are using as the buoyancy characteristics vary depending on the model. For example the difference in buoyancy for a Faber FX-100 and a Faber HP-100 is over 6 lbs. More than your average steel backplate.

    If you are bouncing up and down then it is not the plate's fault it is the wing. You were probably trapping gas and not venting completely. Make sure on the wing you are using that the bladder is reasonable smooth without kinks.

    When doing a weight check you should be able to hold a safety stop at 15 ft with 500 psi in your tank. So you will be starting the dive several pounds heavy because of the weight of air in the tank (about 7.5 lbs for a 100 CF).
     
  7. Dr. Lecter

    Dr. Lecter Solo Diver

    # of Dives: 500 - 999
    Location: NYC/Honolulu
    4,139
    2,923
    113
    If you cannot swim up a full steel 100, a 6lb SS plate, and the other random assortment of crap you listed, sans additional ballast, then you need to forget about playing 'reinvent the wheel with my BP/W' long enough to get yourself some better fins and/or legs. Beyond that, it sounds like you're best left to your own devices on this one. GL.
     
  8. DiveDaddyDale

    DiveDaddyDale Divemaster Candidate

    # of Dives: 100 - 199
    Location: Plano Texas
    44
    3
    0
    Ok, Ok. Thanks all. I appreciate the feedback. I think before I make any more rig modifications I will take the buoyancy class if I can find one here in Dallas. I plan to stick with the aluminum plate and 30lb wing as that seems to be a most recommended combination for us warm water divers.

    BTW; I wear a 3mm full suit even for our hot water lakes as the thermocline drops the temps into the mid 60s below 40'.

    Buoyancy is THE issue. I have focused on reducing weight while considering buoyancy issues also but it will remain a mystery to me why my dive buddy is fine with an AL80 and uses weights, I dive without weights at all and we have the opposite experience with our buoyancy.

    Case she closed pending further investigation.
     
  9. MKrauter

    MKrauter Solo Diver

    # of Dives: 25 - 49
    Location: Windsor, Ontario, Canada
    98
    14
    8
    [TABLE="width: 500"]
    [TR]
    [TD][/TD]
    [TD]AL100 Full[/TD]
    [TD]Al100 Empty[/TD]
    [/TR]
    [TR]
    [TD]Regs[/TD]
    [TD]-3[/TD]
    [TD]-3[/TD]
    [/TR]
    [TR]
    [TD]Tanks[/TD]
    [TD]-4[/TD]
    [TD]+2[/TD]
    [/TR]
    [TR]
    [TD]Backplate[/TD]
    [TD]-6[/TD]
    [TD]-6[/TD]
    [/TR]
    [TR]
    [TD]Lights[/TD]
    [TD]-3[/TD]
    [TD]-3[/TD]
    [/TR]
    [TR]
    [TD]Wetsuit[/TD]
    [TD]+6[/TD]
    [TD]+22[/TD]
    [/TR]
    [TR]
    [TD]Subtotal[/TD]
    [TD]-10[/TD]
    [TD]+12[/TD]
    [/TR]
    [TR]
    [TD]Weight Belt[/TD]
    [TD]-12[/TD]
    [TD]-12[/TD]
    [/TR]
    [TR]
    [TD]Subtotal[/TD]
    [TD]-22[/TD]
    [TD]0[/TD]
    [/TR]
    [TR]
    [TD]Wing[/TD]
    [TD]+22[/TD]
    [TD]0[/TD]
    [/TR]
    [TR]
    [TD]Total[/TD]
    [TD]0[/TD]
    [TD]0[/TD]
    [/TR]
    [TR]
    [TD]Wing Failure[/TD]
    [TD]-22[/TD]
    [TD]0[/TD]
    [/TR]
    [TR]
    [TD]Drop Weight Belt[/TD]
    [TD]-12[/TD]
    [TD]n/a[/TD]
    [/TR]
    [TR]
    [TD]Total[/TD]
    [TD]-10[/TD]
    [TD]0[/TD]
    [/TR]
    [/TABLE]
    Make a spreadsheet and add in your values when you figure them out...This is an example taken from the GUE-F Workbook. Add in your own values as you can determine the. You must aim to be neutrally buoyant at 10ft with 500psi in your tanks. You should be able to swim up 10lbs from depth easily. If not, work on strengthening your legs or carry less crap.

    D-Rings, Masks, Reels, Lift Bags.. they shouldn't really factor into your equations. Their effects on buoyancy is not drastic unless you're carrying 20 (exaggeration) D-Rings or 10 Lift bags, etc. Depending on your fins you can factor that in your equation as well. It's not rocket science, just take your time and go about it logically.
     
  10. DiveDaddyDale

    DiveDaddyDale Divemaster Candidate

    # of Dives: 100 - 199
    Location: Plano Texas
    44
    3
    0
    Now that list is helpful! I really would have liked to keep the DDS plate w the Glide Harness Adapter if possible so I am putting on my Oxy MkV 30 and testing tonight w the AL80. My guess I that I may still need to use the aluminum plate after all. I will miss the easy harness adjustment and Tobin's fine plate. Let's see how it goes tonight.
     

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