Page 2 of 2 FirstFirst 12
Results 11 to 15 of 15

Thread: Carbon Fiber tanks?

  1. #11
    Grouper
    Join Date
    06/08/2009
    Location
    Bicheno, Tasmania, Australia
    Age
    48
    Posts
    490
    Don't under estimate the effect of wear and tear on tanks. Carbon tanks are fairly delicate (compared to steel/aluminium) and what looks like a little ding/gouge on a metal tank will end the life of a composite tank.
    Cheers, TD.

  2. #12
    TadPole
    Join Date
    06/26/2012
    Location
    Seguin, TX
    Posts
    1

    Carbon Dive 300

    If you want to check out an awesome carbon set, Google Carbon Dive 300. it is a Worthington Cylinder product. it is a chromoly steel inner, carbon fiber outer tank. burst tests show a standard steel cylinder burst at 6,321 psi / 430 bar, but their tank burst at 12,510 psi / 851 bar. The 80 cu ft / 10 liter tank filled is -1 3/8 lbs, +7 lbs EMPTY, if there is roughly 1500 psi remaining of the 4,410 it can be filled to, the bouyancy is +4 1/5 lbs.

    So simple comparison, 80 cu ft steel (st) -to- 10 liter CarbonDive 300 (C):

    Weight: 27.7 lbs (st) / 21.1 lbs

    Bouyancy: -9 lbs Full to -3 lbs Empty (st) -to- -1 3/8 lbs Full to +7 lbs Empty (C)

    Usable capacity: 81 cu ft (st) -to- 106 cu ft (C), if 1600 psi is remaining, you use 81 cu ft of it, the bouyancy is +5 lbs, SO IN ACTUALITY, the steel and carbon tanks both gain 6 lbs of bouyancy if you use 81 cu ft, but the carbon tank still allows 50% more down time.

    Size: 20" L x 7 1/4" D (st) -to- 21 1/2" L x 7 1/8" D (C)

    I have read many posts and threads about the topic of Carbon tanks, I have come to one conclusion, people are forgetting the basics. Either tanks or weights, either way you carry the same weight to the water to obtain that peak bouyancy, the benefits to the carbon include these:
    1) Stronger, by far
    2) Lighter, requiring a wing or BCD with LESS lift, thus smaller, wreck divers, penetration divers, cave divers, listening?
    3) Weight are necessary either way, wouldn't you want to be able to trim your belt, harness, tank(s), backplate PERFECTLY, the carbon tanks allow you to put some of that weight towards your chest, belly, and off your back, ABOVE your center of gravity. Let's be honest divers, even the best of us has caught ourselves wiggling, squirming, flailing, to go flat, belly down trying to obtain a perfect balance and streamline. With the ability to trim forward/under your center of gravity, imagine for just one second, you are drift diving no movement necessary, AT ALL, to maintain a streamlined, flat horizontal, belly down dive, just cruisin' with the drift, and staying on it longer.

    Go to your local Fire station, ask these guys the physical abuse their SCBA's take. they will even maybe drop one on its end just to show you. These tanks are not the everyday run-of-the-mill weak "skeleton" frame carbon tanks, which do have the reputation to cracking or fracturing, thus never being good again. These CarbonDive tanks have a solid CHROMOLY STEEL core tank inside of them, that is twice heat treated, ultrasonically tested, AND hydro'ed, PLUS the Carbon Fiber shell exterior.

    See you all under. Come up SMART, go home SAFE, LIVE TO DIVE AGAIN.

  3. #13
    Grouper
    Join Date
    01/18/2010
    Location
    Gulf Coast, Florida
    Age
    50
    Posts
    282
    Images
    3
    As a Cavern diver who uses steel tanks I see no real benefit to using lead if I don't have to. To the issue of adding weight for proper trim diving. Proper selection and placement of gear will in most cases negate the need for adding lead for buoyancy and or trim. That goes for most of the Cave/Cavern divers I know. IMO AL tanks are good for stage or bailout. Why add lead if you don't have to?
    There is a God... Come diving I'll show you!!
    Just found out I'm an Infidel! Translation: FREE!!

  4. #14
    Barracuda
    Join Date
    08/24/2007
    Location
    Lafayette, Indiana United States
    Posts
    1,904
    Quote Originally Posted by cycleBret View Post
    If you want to check out an awesome carbon set, Google Carbon Dive 300. it is a Worthington Cylinder product. it is a chromoly steel inner, carbon fiber outer tank. burst tests show a standard steel cylinder burst at 6,321 psi / 430 bar, but their tank burst at 12,510 psi / 851 bar. The 80 cu ft / 10 liter tank filled is -1 3/8 lbs, +7 lbs EMPTY, if there is roughly 1500 psi remaining of the 4,410 it can be filled to, the bouyancy is +4 1/5 lbs.

    So simple comparison, 80 cu ft steel (st) -to- 10 liter CarbonDive 300 (C):

    Weight: 27.7 lbs (st) / 21.1 lbs

    Bouyancy: -9 lbs Full to -3 lbs Empty (st) -to- -1 3/8 lbs Full to +7 lbs Empty (C)

    Usable capacity: 81 cu ft (st) -to- 106 cu ft (C), if 1600 psi is remaining, you use 81 cu ft of it, the bouyancy is +5 lbs, SO IN ACTUALITY, the steel and carbon tanks both gain 6 lbs of bouyancy if you use 81 cu ft, but the carbon tank still allows 50% more down time.

    Size: 20" L x 7 1/4" D (st) -to- 21 1/2" L x 7 1/8" D (C)
    So you are basically comparing a larger composit cylinder to a typical steel smaller cylinder.
    I have read many posts and threads about the topic of Carbon tanks, I have come to one conclusion, people are forgetting the basics. Either tanks or weights, either way you carry the same weight to the water to obtain that peak bouyancy, the benefits to the carbon include these:
    This is actually not true. You do not 'always' carry the same physical weight to the water for a given capacity of air. A good example of that is the OMS LP85 tank vs the Luxfer AL80 tank. These two tanks are the same weight on land. When empty, under water the OMS LP85 is neutral and the Luxfer AL80 is 4lbs positive. This means you have to carry 4lbs of lead to make the tank neutral for the AL tank and therefore the rig is 4lbs heavier overall.

    1) Stronger, by far
    Dubious. A tank needs to be only as strong as required to meet design spec. There is no useful difference for the end-user.

    2) Lighter, requiring a wing or BCD with LESS lift, thus smaller, wreck divers, penetration divers, cave divers, listening?
    Lift is determined by the total package, not just the tank. Since you now have a positively buyant tank when empty, you have to add lead and your wing now has to lift the weight of the lead as well. Lift is also required for 'swing' in the tank. The more air you carry, the more swing in wieght you get and the more lift you need to handle the 'full' tank(s).

    Since I dive caves with double LP104's, in you suggestion, I would take my PST tanks which are negative empty and replace them with these. I still have the 16+lbs of air swing and now add 20+lbs of lead for the positive buoyancy characteristics of the tank and I still need my 50lb wing once everything is said and done.

    3) Weight are necessary either way, wouldn't you want to be able to trim your belt, harness, tank(s), backplate PERFECTLY, the carbon tanks allow you to put some of that weight towards your chest, belly, and off your back, ABOVE your center of gravity. Let's be honest divers, even the best of us has caught ourselves wiggling, squirming, flailing, to go flat, belly down trying to obtain a perfect balance and streamline. With the ability to trim forward/under your center of gravity, imagine for just one second, you are drift diving no movement necessary, AT ALL, to maintain a streamlined, flat horizontal, belly down dive, just cruisin' with the drift, and staying on it longer.
    The question of wieght is personal. There may be advantages to using lead and there are advantages to not using lead. There is no concrete answer for every diver.

    Go to your local Fire station, ask these guys the physical abuse their SCBA's take. they will even maybe drop one on its end just to show you. These tanks are not the everyday run-of-the-mill weak "skeleton" frame carbon tanks, which do have the reputation to cracking or fracturing, thus never being good again. These CarbonDive tanks have a solid CHROMOLY STEEL core tank inside of them, that is twice heat treated, ultrasonically tested, AND hydro'ed, PLUS the Carbon Fiber shell exterior.

    See you all under. Come up SMART, go home SAFE, LIVE TO DIVE AGAIN.
    I own a few carbon fiber tanks. They have the same issues all composite tanks have. They are much better than the old fiberglass hoop wrapped tanks but they are far from perfect.

  5. #15
    Instructor, Technical & Cave Diver "Forum Admin" TommyB's Avatar
    Join Date
    07/10/2007
    Location
    Orlando, Fl.
    Age
    59
    Posts
    846
    Images
    45
    2) Lighter, requiring a wing or BCD with LESS lift, thus smaller, wreck divers, penetration divers, cave divers, listening?
    I'm reading. not sure I'm listening though
    3) Weight are necessary either way, wouldn't you want to be able to trim your belt, harness, tank(s), backplate PERFECTLY, the carbon tanks allow you to put some of that weight towards your chest, belly, and off your back, ABOVE your center of gravity. Let's be honest divers, even the best of us has caught ourselves wiggling, squirming, flailing, to go flat, belly down trying to obtain a perfect balance and streamline. With the ability to trim forward/under your center of gravity, imagine for just one second, you are drift diving no movement necessary, AT ALL, to maintain a streamlined, flat horizontal, belly down dive, just cruisin' with the drift, and staying on it longer.
    I cave 3 to 4 times a week. I don't use any/extra weight.
    Dry Suit, with 400 gram polar-tech undies.
    side mounting either HP 100's or LP 95s. (both Worthington)

    For drifts it's either HP80's or HP 100's doubles again Worthington using a transpac eg softplate.
    So, I'm going to have to disagree with
    Weight are necessary either way
    I guess if I dove AL's i'd have to use weights.
    Tommy Burchfield Naui/TDI/SDI
    if ( $clue == \'none\' ) { read ( sig & avatar rules | forum rules ) && search ( forums | google ) }
    if ( $answer == 0 ){ post->question }

Page 2 of 2 FirstFirst 12

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Mares Carbon 42 Regulator
    By ScubaToys Larry in forum New Product RSS
    Replies: 1
    Last Post: 01-05-2011, 14:59
  2. Mares Razor Carbon Fin
    By Largo in forum Free Diving
    Replies: 8
    Last Post: 09-19-2010, 07:19
  3. fiber optic mounting
    By gee in forum Gear Information
    Replies: 12
    Last Post: 05-05-2009, 20:39
  4. Carbon Fiber Tanks
    By SlvrDragon50 in forum Scuba Stories, Comments & Questions that don't fit elsewhere!
    Replies: 29
    Last Post: 09-10-2008, 00:22
  5. Carbon Fiber?
    By yankeefan21 in forum Tanks
    Replies: 23
    Last Post: 10-22-2007, 18:28

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •