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Cave fills?

Discussion in 'NorCal' started by Brett Hatch, Mar 17, 2020.

  1. CaveSloth

    CaveSloth Manta Ray

    # of Dives: 50 - 99
    Location: The Deep South
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    Any reason why a steel cylinder from the 1970s can't be overfilled same as a new steel cylinder if it passes hydro?
     
  2. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,834
    2,891
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    Steel 72's aren't the same as lp85's
     
    Caveeagle likes this.
  3. CaveSloth

    CaveSloth Manta Ray

    # of Dives: 50 - 99
    Location: The Deep South
    565
    162
    43
    Oh? So it isn't just like an "LP72"? Unsafe to overfill?
     
  4. BRT

    BRT Giant Squid

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    I'm certainly not comfortable pumping old steel 72's to 3800. But some do. Nobody has yet come up with a failure of a steel scuba tank in hydro and viz.
     
  5. Superlyte27

    Superlyte27 Cave Instructor

    # of Dives: 5,000 - ∞
    Location: Florida
    3,834
    2,891
    113
    I won't do it, if you cut one in half those tanks are thin as hell.
     
    Caveeagle likes this.
  6. SandyRobinson

    SandyRobinson Manta Ray

    # of Dives: 500 - 999
    Location: Moultrie, Georgia
    843
    250
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    I limit mine to 2500 and have written that across the neck of the tank as a reminder to the fill station.
     
    KWS and Caveeagle like this.
  7. Dark Wolf

    Dark Wolf Solo Diver

    # of Dives: 200 - 499
    Location: SW Missouri
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    I cant help with the shops in your area. Sorry.

    I regularly fill my LP95 doubles to 4k. My LP85 doubles also get overfilled to 3500 or so.

    As stated upthread, when I get my LP72 sets assembled they will be overfilled, though not as high.

    DW
     
  8. Caveeagle

    Caveeagle Rebreather Pilot

    # of Dives: 500 - 999
    Location: High Springs, FL
    1,596
    1,095
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    LP108 and HP100 are totally different tanks and sizes. The 108s are 8” diameter and significantly fatter tanks.

    From an internal volume standpoint, your HP100 tanks are pretty much the same as LP85s. The 100s have a bit thicker steel and are a tad heavier. If you are diving salt water, and possibly dry-suit, you are far better off staying with the HP100 tanks.

    one of the only reasons LP85 / LP108 type tanks work well for cave diving is that they rarely get breathed down more than 2/3rds of the initial fill. So even at the end of a typical cave dive, they are still a little negative.

    no evidence to support this.

    like CaveSloth, I have a set of LP104s that have born on dates from the early 70s that were purchased from a well known Florida cave explorer. I am quite certain these babies were hydro’d far more often than the required 5yr interval. They past their last “official” hydro in 2018.

    I also have 3 pair of old LP72s that are all in use. I will fill these up to around 2600, which makes them great for single tank, or SM cavern diving. As has been stated, they are thin, and there is no way I would pump them up as high as modern LP tanks.
     
    KWS likes this.
  9. broncobowsher

    broncobowsher Solo Diver

    1,325
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    And if you are in a place that doesn't have over fills, does it really matter?
    Yes, in Florida you can get cave fills. The rest of the world that would be a shop that accidently filled an LP tank thinking it was another AL80.
    I have had one boat (that is no longer in business) in California that gave me a 3800 fill, once. I think the deckhand was distracted or the gauge was broken.
     
  10. KWS

    KWS ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: SE TEXAS
    4,617
    1,138
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    One opinion is based on experience and the other is based on what they have been told to believe.
     

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