How long before someone chimes in with "Get a BP/W"?
:d
:d
BCD/WEIGHT is it me or the bcd
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fbk
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Namreg 58
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Lose the full face mask if you want to reduce your buoyancy......think about it!!!!!
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I have a couple of suggestions which may have already been repeated.
One is that BC only has two flat dump valves operated by the I3 as far as I can tell. (I just watched the video) So that means one on top and one on the bottom. If any part of the wing is higher than the top one, when you dump air vertically some may still be inside. With the bungees it may be hard to tell since they're flattening the wing. Or possibly they're also trapping air between them. Probably the best way to tell is have someone watch it carefully, maybe take pictures/video so you can later see if that is a problem. Try floating horizontally to magnify the problem if there is one - i.e. any puffiness in the wing is an indication there's still air trapped. Maybe the platform at SeaBase is a good spot if the water is clear enough.
One other thing that may be related is that the Dimension has a 50# lift wing. My doubles wing is 55#. A comparable cold water BC like a Ranger or SP Knighthawk has a 44lb. wing. So unless the I3 is performing optimally, you may have trapped some air during most of your dives.
Someone else mentioned it but with certain models there are gyrations you go thru to optimize getting all the air out. My first back wing (decades ago) I had to tip my left shoulder higher than the right, it was more of a horseshoe wing with the inflator in an odd place. That one didn't have any bottom dumps.
Both the Ranger and the Knighthawk have 2 upper dumps, both are pull-downs on the shoulders plus 2 bottom (on the Ranger, IDK about the Knighthawk) They're provided for a reason.
Dimension I3's are pretty popular, I think this issue would have surfaced before if there's a flaw in the design. Looking at the chart on the Aqualung site, it appears that 30lbs. is the max recommended weight for that model (20 jettisonable) so you may need a belt to go beyond that. When you have all that weight in it, how does it trim?
Or a different BC - you mentioned a Ranger, they're 30# front/ 20# rear - all of which is jettisonable.
With not a lot of dives, some of dropping weight is just getting used to your gear and dialing in your buoyancy. Maybe either pay a DM/Instructor to work with you once on that or take a Peak Buoyancy course. I started out diving in SoCal with about 30+lbs (7mil suit) A few months later my cold water weight was 24#. I never managed to get much below that. If I go a little too light (20-22lbs.) I have to fight to get down but can usually stay down at depth once I get all the air out of my wing. Less than that that when I try to hold at depth, I will slowly float up. Once I left my trim weights on the boat and fought the whole dive to stay down until the DM took pity on me and loaned me some weight.
There is some inherent buoyancy with that design, all the foam in the lumbar pad, plus it looks like some parts of the Wrapture are also padded. So you're fighting 5-6lbs. inherent buoyancy most likely w/o any air in it. Most padded BC's have this problem to an extent - it's why BP/W's are popular options - esp. with cave/wreck divers since both need pinpoiint buoyancy control to keep from banging into things/silting things up.
hth,
One is that BC only has two flat dump valves operated by the I3 as far as I can tell. (I just watched the video) So that means one on top and one on the bottom. If any part of the wing is higher than the top one, when you dump air vertically some may still be inside. With the bungees it may be hard to tell since they're flattening the wing. Or possibly they're also trapping air between them. Probably the best way to tell is have someone watch it carefully, maybe take pictures/video so you can later see if that is a problem. Try floating horizontally to magnify the problem if there is one - i.e. any puffiness in the wing is an indication there's still air trapped. Maybe the platform at SeaBase is a good spot if the water is clear enough.
One other thing that may be related is that the Dimension has a 50# lift wing. My doubles wing is 55#. A comparable cold water BC like a Ranger or SP Knighthawk has a 44lb. wing. So unless the I3 is performing optimally, you may have trapped some air during most of your dives.
Someone else mentioned it but with certain models there are gyrations you go thru to optimize getting all the air out. My first back wing (decades ago) I had to tip my left shoulder higher than the right, it was more of a horseshoe wing with the inflator in an odd place. That one didn't have any bottom dumps.
Both the Ranger and the Knighthawk have 2 upper dumps, both are pull-downs on the shoulders plus 2 bottom (on the Ranger, IDK about the Knighthawk) They're provided for a reason.
Dimension I3's are pretty popular, I think this issue would have surfaced before if there's a flaw in the design. Looking at the chart on the Aqualung site, it appears that 30lbs. is the max recommended weight for that model (20 jettisonable) so you may need a belt to go beyond that. When you have all that weight in it, how does it trim?
Or a different BC - you mentioned a Ranger, they're 30# front/ 20# rear - all of which is jettisonable.
With not a lot of dives, some of dropping weight is just getting used to your gear and dialing in your buoyancy. Maybe either pay a DM/Instructor to work with you once on that or take a Peak Buoyancy course. I started out diving in SoCal with about 30+lbs (7mil suit) A few months later my cold water weight was 24#. I never managed to get much below that. If I go a little too light (20-22lbs.) I have to fight to get down but can usually stay down at depth once I get all the air out of my wing. Less than that that when I try to hold at depth, I will slowly float up. Once I left my trim weights on the boat and fought the whole dive to stay down until the DM took pity on me and loaned me some weight.
There is some inherent buoyancy with that design, all the foam in the lumbar pad, plus it looks like some parts of the Wrapture are also padded. So you're fighting 5-6lbs. inherent buoyancy most likely w/o any air in it. Most padded BC's have this problem to an extent - it's why BP/W's are popular options - esp. with cave/wreck divers since both need pinpoiint buoyancy control to keep from banging into things/silting things up.
hth,
I cannot see that anyone has commented on proper descenttecniques.
A common problem with fresh divers is exhaling too soon, and finning too much.
When you need to descend follow these steps. (Order IS important)
1. Breathe normally
2. Insert 2 stage
3. Start to deflate your BC. Hold the hose properly above your head.
4. Take a DEEP breath in, and hold while you continue to deflate air from your BC.
5. Cross your legs at the ankles and bend slightly in the knees. (This will stop any finning, and force you slightly forward towards horizontal)
6. When you feel you have expelled most of the air from your bc, exhale untill you are 4-6 feet under water.
7. Breathe normally.
On your next dive, make sure your do a proper weight check on a close to empty tank.
I have never used anything other than a drysuit in cold water, but this technique really helps on the students we teach here in Norway. And they dive in drysuits.
A common problem with fresh divers is exhaling too soon, and finning too much.
When you need to descend follow these steps. (Order IS important)
1. Breathe normally
2. Insert 2 stage
3. Start to deflate your BC. Hold the hose properly above your head.
4. Take a DEEP breath in, and hold while you continue to deflate air from your BC.
5. Cross your legs at the ankles and bend slightly in the knees. (This will stop any finning, and force you slightly forward towards horizontal)
6. When you feel you have expelled most of the air from your bc, exhale untill you are 4-6 feet under water.
7. Breathe normally.
On your next dive, make sure your do a proper weight check on a close to empty tank.
I have never used anything other than a drysuit in cold water, but this technique really helps on the students we teach here in Norway. And they dive in drysuits.
Over 30 pounds with a 3 mil wetsuit tells me something is wrong. I'm quite sure that, if you got in the water with just the wetsuit, and no other gear, you'd sink like a stone with 30 pounds on you. Your i3, empty, with an empty aluminum tank, should not be more than 10 lbs positive at MAX. So, somewhere, you are picking up about 15 pounds of buoyancy that you don't need.
The possibilities include kicking -- this is a very common one. If you are unstable on the surface, you will kick to maintain position, and since your fins are beneath you, it makes it hard to descend. You can test this by crossing your ankles before you deflate the BC -- you may not descent in a nice, vertical postion, but if it is suddenly much easier to get under the water, you were kicking yourself up. In addition, during a dive, if you swim in a head-up orientation, you are constantly kicking yourself upward in the water column. This means you have to have enough weight to counter that force. A buddy can give you feedback on this, or you can just try stopping all motion and seeing if you suddenly start to sink. If so, you are diving negative and kicking up.
Another is anxiety. When we are nervous, we tend to hold a lot of air in our lungs, and new divers are notorious for doing this. If you are a large-framed person and you are keeping your lungs full, you're swimming around with about five pounds of buoyancy you have to counter. Allowing yourself to relax and exhale helps this, and this is the biggest part of the reason that new divers often shed several pounds over the first dozen dives or so.
Another possibility has been mentioned, and that is that the rather large air bladder on your BC is trapping air. Anything you can't vent, you have to carry lead to sink. Not only is that annoying, but it also contributes to buoyancy problems, because the trapped air is expanding and contracting as you move in the water column.
The first thing I would do, if I were you, would be to schedule some time with a buddy to do some weight checking. Even if this is in a fresh water pool, it will be useful. What you want to do is determine the minimum amount of weight that will keep you underwater with an empty BC. I'd suggest putting a little less weight in the BC than you think you need, and then having perhaps a bag or a weight belt with some 2 lb weights on it. Get to the bottom however you can, and vent your BC until you are sure it is empty. Your buddy can then look at the air bladder and feel it, and find out if it's trapping air or if you have it empty. If you do, then the buddy can remove the 2 lb weights one at a time, until you can't lie on the bottom any more. If you do this with a full Al80, you need to add five more pounds to account for the air in the tank that you are going to lose as the dive progresses, and if you do it in a pool, you need to add 2.5% of the total weight of you and the gear to account for salt water -- this is usually in the neighborhood of 5 to 7 pounds.
My guess is that your BC is probably about 3 lbs positive when empty, and the tank is -2 when full, so most of the weight you need should just be to sink the 3 mil wetsuit, which shouldn't be more than ten pounds. With the 7 mil suit, you will need more, and with a dry suit, more yet; I dive with 31 pounds of ballast with a steel tank in Puget Sound in a dry suit, and I'm 5'4" and 120 lbs. But given the information you have put in your post, either you have some upward force coming from something -- kicking, excess lung volume, or BC air trapping -- or you are grossly overweighted.
The possibilities include kicking -- this is a very common one. If you are unstable on the surface, you will kick to maintain position, and since your fins are beneath you, it makes it hard to descend. You can test this by crossing your ankles before you deflate the BC -- you may not descent in a nice, vertical postion, but if it is suddenly much easier to get under the water, you were kicking yourself up. In addition, during a dive, if you swim in a head-up orientation, you are constantly kicking yourself upward in the water column. This means you have to have enough weight to counter that force. A buddy can give you feedback on this, or you can just try stopping all motion and seeing if you suddenly start to sink. If so, you are diving negative and kicking up.
Another is anxiety. When we are nervous, we tend to hold a lot of air in our lungs, and new divers are notorious for doing this. If you are a large-framed person and you are keeping your lungs full, you're swimming around with about five pounds of buoyancy you have to counter. Allowing yourself to relax and exhale helps this, and this is the biggest part of the reason that new divers often shed several pounds over the first dozen dives or so.
Another possibility has been mentioned, and that is that the rather large air bladder on your BC is trapping air. Anything you can't vent, you have to carry lead to sink. Not only is that annoying, but it also contributes to buoyancy problems, because the trapped air is expanding and contracting as you move in the water column.
The first thing I would do, if I were you, would be to schedule some time with a buddy to do some weight checking. Even if this is in a fresh water pool, it will be useful. What you want to do is determine the minimum amount of weight that will keep you underwater with an empty BC. I'd suggest putting a little less weight in the BC than you think you need, and then having perhaps a bag or a weight belt with some 2 lb weights on it. Get to the bottom however you can, and vent your BC until you are sure it is empty. Your buddy can then look at the air bladder and feel it, and find out if it's trapping air or if you have it empty. If you do, then the buddy can remove the 2 lb weights one at a time, until you can't lie on the bottom any more. If you do this with a full Al80, you need to add five more pounds to account for the air in the tank that you are going to lose as the dive progresses, and if you do it in a pool, you need to add 2.5% of the total weight of you and the gear to account for salt water -- this is usually in the neighborhood of 5 to 7 pounds.
My guess is that your BC is probably about 3 lbs positive when empty, and the tank is -2 when full, so most of the weight you need should just be to sink the 3 mil wetsuit, which shouldn't be more than ten pounds. With the 7 mil suit, you will need more, and with a dry suit, more yet; I dive with 31 pounds of ballast with a steel tank in Puget Sound in a dry suit, and I'm 5'4" and 120 lbs. But given the information you have put in your post, either you have some upward force coming from something -- kicking, excess lung volume, or BC air trapping -- or you are grossly overweighted.
What she said, without a doubt. I hate to say it, but go rent a basic jacket BCD, hit the pool and do a side by side test for your weight. You should be the same or a few pounds the same. If the LDS that sold you the I3 has pool access ask them for the rental and go from there. My LDS bends over backwards when theres an issue. 30lbs is sick; unless you should weigh 150 and are carrying the rest as fat....just saying.
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They already did. I think it was the third post?
---------- Post added June 28th, 2013 at 09:57 AM ----------
Why are you using a full face mask? That's a very strange choice for a newby diver and wouldn't be my first recommendation
I'd recommend spending a few hours with a good instructor, either as a private lesson or take a peak performance buoyancy class.
I also like the recommendation to separate out the weight needs of your rig and your suit as was suggested in a post above.
There is a book called "The Six Skills" which I highly recommend reading. Although its geared more towards advanced divers, it has a great deal of advice for divers of any stage. While I was reading it I kept thinking "Why doesn't anybody tell us these things?". Anyway, the author goes into great detail about checking your bouyancy. He actually recommends using a fish scale to test the bouyancy of your rig.
---------- Post added June 28th, 2013 at 10:32 AM ----------
This is one of the best explanations on how to work out your weight requirements I think I've ever seen, at least on Scuba Board!
I might add that, if the OP decides he would like to get a drysuit, every type of undergarment is different and requires a different amount of weight.
When doing this pool weight check, have your buddy actually try to squeeze out any trapped air in the BC, which will give you a good idea if the BC is the culprit.
I used to have a BC that had a strange bubble to manage and would not only cause me to "list" with my left side down but also required me to roll side to side repeatedly in order to dump all of the air if I was in a horizontal position. Strange, given that this was a very lightweight travel BC with far too little lift for most people. I don't require a lot of weight, especially if I'm diving in a Lycra skin in AZ summer but it was enough to cause annoying issues.
Finally, it's very important to check weighting anytime you do even minor gear adjustments. Gear like fins, flashlights and different hood thicknesses all cause slight weight changes. We are very lucky to have our own pool, which allows us to do gear and weight checks before every trip or after any change to our rig.
I use the full face mask because when I dove with a standard mask, even with de fog I couldn't go a dive without it fogging up. I also liked the fact that I can breath through my nose and don't get dry mouth from it.
I think I will take all my gear and go to my lds and hire an instructor and weight out each piece of equipment. Why did they not do this when going through the class.
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30 lbs may or may not be reasonable. TSandM uses 32 with her drysuit and I know for a fact she's done everything in her power to try to drop the weight. Yet, she can't. And, she's a little person, too.
40 lbs does sound extreme, as does the 30 lbs in a 3ml, though.
---------- Post added June 28th, 2013 at 10:36 AM ----------
Did you scrub your brand new mask with toothpaste? That needs to be done, inside and out. Sometimes it takes 2-3 sessions of scrubbing. Did your instructor tell you about adding just a few drops of water to your mask and keeping it there so that it doesn't fog? You can move your head around to distribute the bit of water in the bottom if the mask very so often if it's starting to fog up.
Are you able to clear your full face mask when it floods? Can you swim underwater, breathing off your regulator without your mask? Oftentimes, the FFM is used as a crutch to avoid the issues new divers have with mask clearing, mask floods and having to breathe through the mouth on a regulator without the mask on. If you had any issue with those skills I would make sure those get solid and you continue to practice them. I'd hate to see you have a mask flood or mask ripped off in current and not be prepared. It can be especially scary in cold water if you haven't practiced in awhile. This is probably the most difficult skill for new students, especially when training in cold water but once you learn it, it's really not hard at all.
Anyway, I'm derailing this thread. If you did have mask issues in your OW class, I'd suggest starting a thread on this. I'm sure you'll get that problem figured out, too, with the help of Scuba Board.
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