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TRACI
11-02-2007, 15:57
Is the some certain secret to having proper buoyancy in saltwater? The DM's say that I have entirely too much weight, but when I reduce my weight I have trouble making a safety stop and a control ascent.

RoadRacer1978
11-02-2007, 16:03
The only real secret I know is experience. With each dive I get a little better. I know this really doesn't help you, but if you cannot stop to do your safety stop then I'd say you need more weight. Making very small adjustments during the dive and waiting long enough for those adjustments to take effect really helps me. Also breathing helps. I try to use my lung volume to help me. As I am descending I will take deeper breaths if I notice myself getting a little negative. I can use my lung volume to make small changes in bouyancy while I am fine tuning everything on my BCD and waiting for those small changes to take effect. This is probably really confusing as I am confusing myself as I try to write this out. Maybe someone can put my thoughts together into a much easier to understand format. :)

Aspendiver
11-02-2007, 16:13
It also helps to make sure that all of the air is out of your BCD before your safety stop. Depending on your BCD, there are different ways to do this... look where the air exits the BC, and figure out how to make that the highest point on your body in the water. For some, that means holding the exhaust straight up, tipping your left shoulder up higher than the right, and arching your back a bit.


Then, put your left foot behind your right ear, your right foot behind your left shoulder blade...
<<<< :smiley2: >>>>

MSilvia
11-02-2007, 16:14
The secret, if you want to call it that, is to do your weight check with a nearly empty tank. If you know you are neutral near the surface with an almost used up tank, you also know you'll be heavier at the beginning of the dive, as you'll have several pounds of additional air with you then. The extra weight of your breathing gas will help you get under, and as you get deeper, your wetsuit will compress a bit, making it easier to stay down until the end of the dive.

With all due respect to DMs, what they say you need has no bearing on what you actually need. Only experience will tell you that.

TRACI
11-02-2007, 16:17
I have also tried distributing in different areas, because I always end up diving in a verticle position. I may try putting some weight by my tank valve to see if that helps

DevilDiver
11-02-2007, 17:07
If you have issues with the saftey stop try this out. Usually once you can master the saftey stop in open water the rest of the issues seem to go away.....................

http://www.scubatoys.com/store/accessories/signal/pics/safety_anchor.jpg (http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=SafetyAnchor)
Safety Stop Anchor (http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=SafetyAnchor)

Safety Stop Anchor


Fits in its own little bag 6 x 2 x 2 inches, and has a clip to mount to your bc, or just throw it in a pocket. When you need to do a safety stop, simply pull it out and inflate with your regulator. The large, visible, orange float that measures 2' long and a foot wide will float to the surface. You clip on to the included string with clips at both 10 and 15 foot to accurately wait out your safety stop time while signaling boats where you are.

Great safety item and a must for diving in areas with currents!

Price: $19.95
Signaling Devices, Tubes, Dive Alert (http://www.scubatoys.com/store/Scuba_Acc_signal.asp)

TRACI
11-02-2007, 17:22
I may try that, I was trying to decide between a safety sausage or that.

Chad
11-02-2007, 17:24
A safety sausage is better as a signaling device.

MSilvia
11-02-2007, 17:32
A safety sausage is better as a signaling device.
...Unless you need to signal before you get to the surface. In a swift current, a 3 minute ascent followed by a 3 minute safety stop may move you a considerable distance from the boat. With an SMB deployed from depth, the boat's crew can follow you. With a safety sausage, they can't until you surface.

That said, neither one will help you get your buoyancy right.

DevilDiver
11-02-2007, 17:32
A safety sausage is better as a signaling device.

True, I marked 10',15' and 20' off on the line on my reel attached to my Saftey Sausage. It works for a nice visual reference....:smiley29:

The Saftey Anchor only has 15' of line and a clip at the end. Attach to a D-ring and breathe until you tune it in and it's all good......:smiley32:

I carry it on trips and if there is some one having issues I let them use it. So far it has always helped.................:smiley2:

comet24
11-02-2007, 17:45
Practice and experience are the only answer. No big secret. Being properly weighted does help. After a dive with a tank with only about 500 psi in it try weighting yourself.

Splitlip
11-02-2007, 17:48
I have also tried distributing in different areas, because I always end up diving in a verticle position. I may try putting some weight by my tank valve to see if that helps
When a diver is over weighted, too much gas migrates to the highest point of the BC, typically shoulders. Tends to hold you up like a marionette.

So getting proper weighting/buoyancy mitigates this.
Moving the weight on your body improves trim. This often has to be done to compensate for you body and build.

Try moving your cylinder. If you are using trim weights, you just may be better off moving that weight to your cylinder bands if they are higher than your trim pockets.

Keep experimenting with moving the weight. You may have to remove weight from your belt and or ditchible pockets and move that to the cylinder strap.

Or, as I finally did. Backplate and couple of pounds on the upper cylinder straps.

peteg
11-02-2007, 17:50
A Peak Performance Bouyancy (or similar) class with a *good* instructor might be helpful too.

texdiveguy
11-02-2007, 17:51
Is the some certain secret to having proper buoyancy in saltwater? The DM's say that I have entirely too much weight, but when I reduce my weight I have trouble making a safety stop and a control ascent.

Hi Traci..... no sure fired answer to your question.....most folks will find it a wee-bit easier to establish good bouyancy in salt water verse fresh water. Practice and repeated diving are the 2 best components to maintaining a suitable safety stop. I know of few divers new and experienced whom don't at times have issues with buoyancy particulary when doing a shallow safety stops. I have no experience with the Safety Stop Anchor (chuckle)....but I would concentrate on breathing...relaxing and refining your trim. Remember that there are several factors effecting you in the upper 30ft. of the water column not to mention what Mother Nature might decide to throw your way. Try and hit your local fresh water dive spot,,,maybe CSSP and practice....this will go a long way in doing your best once hitting Coz.. Safe and fun diving!!

WaScubaDude
11-02-2007, 17:55
Is the some certain secret to having proper buoyancy in saltwater? The DM's say that I have entirely too much weight, but when I reduce my weight I have trouble making a safety stop and a control ascent.

Safe to assume you are not in a drysuit? Drysuits make the issue more complicated.
Also, really learn and use all of your dump valves. I see divers struggle to get down that don't know to pull the dump valve at the bottom of the bc.
Sometimes there is a bit of air left in the bc and it can be helpful.
ie: At the surface you put head down legs up, as you sink a bit pull the string on the bottom dump. Also good to learn if you are "corking" or out of control ascending, as you can turn head down, fin kick to slow your ascent and dump air from the bottom valve. All this assues you have a dump valve at the bottom.

Chad
11-02-2007, 18:09
I carry it on trips and if there is some one having issues I let them use it. So far it has always helped.................:smiley2:

That is a good idea.

vadiver
11-02-2007, 18:20
I'd stay away from that safety stop float (or whatever it is) and spend more time in the water to fine tune your weighting. Adding something extra to a dive in order to compensate for a lack of proper buoyancy skills is a mistake. All that would do is make you reliant upon an extra piece of equipment whereas all you need is more time in the water and some training.

Id advise you take a GUE DIR-F class if you want to get your trim/buoyancy squared away. You can take it in a single tank for recreational or in doubles for a technical progression. Either way that course is the well worth the money.

Chad
11-02-2007, 18:24
A safety sausage is better as a signaling device.
...Unless you need to signal before you get to the surface. In a swift current, a 3 minute ascent followed by a 3 minute safety stop may move you a considerable distance from the boat. With an SMB deployed from depth, the boat's crew can follow you. With a safety sausage, they can't until you surface.

Agreed, but given the option between a safety sausage and the Safety Stop Anchor I would find the safety sausage more useful. It looks like the SS Anchor is only good when you are 15' deep or less.

Personally in open water I dive with a safety sausage, a 50# lift bag, and a couple safety spools.:smiley20:

Sorry for taking this thread off topic.

Puffer Fish
11-02-2007, 19:07
Good buoyancy starts with having the right amount of weight, which should be the zero point, at 15 ft, with a near empty tank... and having enough breath control to go up or down.

Oh, and all the air has to be out of the vest.

The more overweighted you are, the more you have to carry extra air in the bladder and the more it will expand as you go up and contract as you go down.. difficult to manage for anyone.

UCFKnightDiver
11-02-2007, 20:47
sometimes I have trouble with keeping more air in my lungs, and almost to the point of holding me breath, and not exhaling completely when I am doing something a bit more technical or am getting frusturated, make sure that you continue to breathe normally, it is something I am getting better at, I have found this effects boyancy, everones different but I wear about 6 pounds with a 3/2mil wetsuit in freshwater and I am 5'11, and 180 pounds, hope this helps a bit

TRACI
11-12-2007, 11:54
I wear a 3/2 full wetsuit, and I weigh 140 lbs, and I first started with 14, then 12, then 10#'s. But 10 still felt like I lot. Is 10 lbs too much?

MSilvia
11-12-2007, 11:59
Is 10 lbs too much?
I don't know... is it? If you wear 10 lbs and are neutral at safety stop depth at the end of your dive with an empty bc, it's just right. if you're negative at that point, it's too much. If you're so buoyant you can't hold the stop, it's not enough.

No one can tell you how much weight is right for you... you have to figure it out. There is no (accurate) table that says "If you wear such-and-such for exposure protection, and weigh X, you need this amount of weight". The solution to the problem is to dive and adjust, narrowing it down until you know for sure.

If you think 10 is too much, try 8 and see how that works out. If it isn't enough, try 9. If that isn't enough, 10 isn't too much.

dallasdivergirl
11-12-2007, 12:13
It can be a very fine line & as you dive more it will drop more.

I started off diving with 12 lbs and was very over weighted but I was breathing off of the top of my lungs all of the time. Once I really relaxed, the weight dropped ever time I dove. I tried a dive with too little weight & it was a miserable dive. I could not stay down. If 10 lbs is right for you then don't let any one tell you it's too much. You know your diving & what you need to be carrying.

reactive
03-31-2008, 15:47
This is a great thread. I've been searching for some information on getting properly weighted and the right procedure to do it. I've read several different conflicting articles and posts. Some say that you need to don all your gear and hold a breath and be eye level at the surface with an empty tank with no air in your BC. Others say to be at eye level with just your exposure suit and weight belt while holding a breath at the surface.

I do have one more question as this was just vaguely covered in my OW class. Where do I start with weight? I've read 5% - 10% of my body weight, among several different other suggestions. I know there is no set chart that dictates how much weight for a person who wears X exposure suit and weighs X lbs and is X tall, but some sort of guide on where to start would helpful. Also, I'm renting equipment currently. Each time I rent gear, I generally get different BC's with different buoyancies. Should I wait until I buy my own rig to start zeroing in on my weight belt?

For people who go back and forth between Salt and Fresh water:
Do you change the amount of weight you use when going back and forth? Do you find that once you've zeroed in, you can kind of keep your weight belt the same?

thor
03-31-2008, 15:57
Additionally, new gear will add to buoyancy issues. If you don't own your own gear, make sure you try to use the same wetsuit and BC. A new wetsuit will also make you more buoyant at the beginning of a dive. If you do a weight check at the beginning with a new wetsuit, you will probably be overweighted.

obrules15
03-31-2008, 16:00
One of the things that I noticed about proper weighting and safety stops is that the more experienced I got the less I moved my hand and legs during the safety stop which tended to propel me upward so the more I practiced being perfectly still during the stop the less weight I needed. Also on a dive trip I tend to start out the trip heavier and end at least 4 lbs lighter as I improve from day to day.

CompuDude
03-31-2008, 16:21
This is a great thread. I've been searching for some information on getting properly weighted and the right procedure to do it. I've read several different conflicting articles and posts. Some say that you need to don all your gear and hold a breath and be eye level at the surface with an empty tank with no air in your BC. Others say to be at eye level with just your exposure suit and weight belt while holding a breath at the surface.

I do have one more question as this was just vaguely covered in my OW class. Where do I start with weight? I've read 5% - 10% of my body weight, among several different other suggestions. I know there is no set chart that dictates how much weight for a person who wears X exposure suit and weighs X lbs and is X tall, but some sort of guide on where to start would helpful. Also, I'm renting equipment currently. Each time I rent gear, I generally get different BC's with different buoyancies. Should I wait until I buy my own rig to start zeroing in on my weight belt?

For people who go back and forth between Salt and Fresh water:
Do you change the amount of weight you use when going back and forth? Do you find that once you've zeroed in, you can kind of keep your weight belt the same?

Unfortunately, every body type and gear configuration is different, so it's really hard for there to be a rule of thumb that covers all. Best bet is to start at the 10% rule, and test it out in the pool first. Fine tune as needed. (it will likely be needed)

Going from salt to fresh you will be a little heavy, so going the other way, you'll be a little light. As a ballpark, add at least a couple pounds going from the pool to the ocean, and you should be close enough to get started.

Personally, I mostly dive salt water, so I don't change anything when going to fresh water. I can live with being a couple of pounds overweighted.

reactive
03-31-2008, 17:50
This is a great thread. I've been searching for some information on getting properly weighted and the right procedure to do it. I've read several different conflicting articles and posts. Some say that you need to don all your gear and hold a breath and be eye level at the surface with an empty tank with no air in your BC. Others say to be at eye level with just your exposure suit and weight belt while holding a breath at the surface.

I do have one more question as this was just vaguely covered in my OW class. Where do I start with weight? I've read 5% - 10% of my body weight, among several different other suggestions. I know there is no set chart that dictates how much weight for a person who wears X exposure suit and weighs X lbs and is X tall, but some sort of guide on where to start would helpful. Also, I'm renting equipment currently. Each time I rent gear, I generally get different BC's with different buoyancies. Should I wait until I buy my own rig to start zeroing in on my weight belt?

For people who go back and forth between Salt and Fresh water:
Do you change the amount of weight you use when going back and forth? Do you find that once you've zeroed in, you can kind of keep your weight belt the same?

Unfortunately, every body type and gear configuration is different, so it's really hard for there to be a rule of thumb that covers all. Best bet is to start at the 10% rule, and test it out in the pool first. Fine tune as needed. (it will likely be needed)

Going from salt to fresh you will be a little heavy, so going the other way, you'll be a little light. As a ballpark, add at least a couple pounds going from the pool to the ocean, and you should be close enough to get started.

Personally, I mostly dive salt water, so I don't change anything when going to fresh water. I can live with being a couple of pounds overweighted.

What is the proper way to check? fully geared with held breath and go for eye level? Or just the exposure suit and weight belt with a held breath at eye level?

It seems like if I'm fully geared, and I let all the air out of my BC I should sink regardless of holding a breath or not. Also, is it common for you to swim down whether than letting the air out of your BC and sinking? In OW class they had us over weighted and told us to let air out of our BC until I start to sink, then add a tiny bit of air until neutrally buoyant. Is this correct? The more I read on this forum, the more I think I was taught wrong.

CompuDude
03-31-2008, 19:20
What is the proper way to check? fully geared with held breath and go for eye level? Or just the exposure suit and weight belt with a held breath at eye level?

It seems like if I'm fully geared, and I let all the air out of my BC I should sink regardless of holding a breath or not. Also, is it common for you to swim down whether than letting the air out of your BC and sinking? In OW class they had us over weighted and told us to let air out of our BC until I start to sink, then add a tiny bit of air until neutrally buoyant. Is this correct? The more I read on this forum, the more I think I was taught wrong.

There are several schools of thought, and many of them are correct.

Most technical divers will tell you that as long as you can hold a safety/deco stop at 15' with no air in your drysuit or BC, and very low amounts of gas in your tank (~500psi or perhaps less) you're weighted properly. There are tons of methods to reach this equilibrium, including swimming down to the deep end with a pile of 1-2 lb weights, and adding or dropping them to the bottom of the pool until you're properly neutral.

PADI teaches you to do a weight check by dumping all air from your BC (you'll see this is standard among all... you have to get all the air out first), holding a normal breath, and see if you can float vertically with the waterline right at eye level on your mask. Again, this should be done with only 500 psi in your tank. (The weight difference between a full tank and an empty standard Aluminum 80 tank is roughly 5 lbs.) If you do this with a full tank, add 5 lbs to your otherwise normal weight check weight to account for the difference.

Whether you use a precise, hands-on method such as actually trying weight combinations in-water (the most certain method) or using PADI's ballpark method and fine-tuning later, you should get closer to where you need to be.

Note there is also that difference between fresh water and salt water. Until you're sure of your weighting, you may want to add an extra 2-4 lbs for salt water use, vs. your pool weighting.

ChrisA
03-31-2008, 21:33
[quote=reactive;151640]
PADI teaches you to do a weight check by dumping all air from your BC (you'll see this is standard among all... you have to get all the air out first), holding a normal breath, and see if you can float vertically

That's correct but I'd add one more thing. Many new divers will fin durring the PADI-style weight check and not even know they are doing it. I think because they are uncomfortable floating at eyelevel. So tell them to lock their ankles and place their thumbs in their waistband. You have to stop moving or you will move out overweighted

Almost everyone finds that they can shed a pound or two after they have been diving for a whiile, if they dive frequently.

CompuDude
03-31-2008, 22:12
PADI teaches you to do a weight check by dumping all air from your BC (you'll see this is standard among all... you have to get all the air out first), holding a normal breath, and see if you can float vertically

That's correct but I'd add one more thing. Many new divers will fin durring the PADI-style weight check and not even know they are doing it. I think because they are uncomfortable floating at eyelevel. So tell them to lock their ankles and place their thumbs in their waistband. You have to stop moving or you will move out overweighted

Almost everyone finds that they can shed a pound or two after they have been diving for a whiile, if they dive frequently.

Yes, good tip, sorry, I left that out of my write up. I always have my students cross their ankles for the reasons you write.

cummings66
03-31-2008, 22:42
Most technical divers will tell you that as long as you can hold a safety/deco stop at 15' with no air in your drysuit or BC, and very low amounts of gas in your tank (~500psi or perhaps less) you're weighted properly.

I wonder if it's a regional thing. My technical instructor wants me to be heavy at the stop by a few lbs. Call Tobin, he'll say the same thing as well. I could give you a few more names as well, most of the technical instructors want you heavy.

Here's the belief. If you're heavy by a few lbs you can add more air to the suit. On a long deco stop you want to remain motionless, but if you're freezing to death and shrink wrapped you will fidget and that doesn't let you offgas properly. So, to solve that you keep the suit lofted a bit more than normal and that solves the freezing problem.

The theory is if you lose your deco gas you do a stop twice as long on your backgas, that will make you cold. Trying hanging in freezing water shrink wrapped for 20 or 30 minutes without moving a muscle and you'll believe as they do it's far better to have some air in the drysuit at the stop.

That's why I've been told that I need to be a few lbs heavy. I'll get neutral and then add a few lbs, that's it. Your technical instructor apparently doesn't agree with it, and maybe it's because your local waters are warm compared to ours.

Different areas different rules...

CompuDude
03-31-2008, 23:59
Most technical divers will tell you that as long as you can hold a safety/deco stop at 15' with no air in your drysuit or BC, and very low amounts of gas in your tank (~500psi or perhaps less) you're weighted properly.

I wonder if it's a regional thing. My technical instructor wants me to be heavy at the stop by a few lbs. Call Tobin, he'll say the same thing as well. I could give you a few more names as well, most of the technical instructors want you heavy.

Here's the belief. If you're heavy by a few lbs you can add more air to the suit. On a long deco stop you want to remain motionless, but if you're freezing to death and shrink wrapped you will fidget and that doesn't let you offgas properly. So, to solve that you keep the suit lofted a bit more than normal and that solves the freezing problem.

The theory is if you lose your deco gas you do a stop twice as long on your backgas, that will make you cold. Trying hanging in freezing water shrink wrapped for 20 or 30 minutes without moving a muscle and you'll believe as they do it's far better to have some air in the drysuit at the stop.

That's why I've been told that I need to be a few lbs heavy. I'll get neutral and then add a few lbs, that's it. Your technical instructor apparently doesn't agree with it, and maybe it's because your local waters are warm compared to ours.

Different areas different rules...

Regional thing. Obviously, air in the drysuit is pretty important where you are. Of course, I'd rather be cold than bent. (Yes, I'm aware there is a possibility of one leading to the other, but that's pretty much aside from the point I'm making about getting neutral first, and then fine tuning for specific needs.) :)

cummings66
04-01-2008, 12:58
If you're heavy it's no big deal to have air in the suit, you're still neutral at the stop. I could see diving shrink wrapped in nice warm temperatures like you guys got though.

Around here you'd need an operation afterwards.:smiley2:

You are quite correct that you absolutely do NOT want to be light and doing deco dives, sure fire way to make a chamber dive that's not for fun.

RoyN
04-01-2008, 13:46
Go make some muscles too! Also a six pack is great! :D

Ever since I started developing big muscles, my buoyancy has been screwed to many times. :(

EuphoriaII
04-03-2008, 17:19
It also helps to make sure that all of the air is out of your BCD before your safety stop. Depending on your BCD, there are different ways to do this... look where the air exits the BC, and figure out how to make that the highest point on your body in the water. For some, that means holding the exhaust straight up, tipping your left shoulder up higher than the right, and arching your back a bit.


I had initially had trouble staying under at the safety stop until I got better at getting ALL the air out of my BC. Remember that as you rise from the bottom, any air in the BC is expanding and more likely to continue to carry you to the surface. Assuming I'm wearing a wetsuit (bouyant) I've usually let nearly all the air out of my bc by 20 ft. I control bouyancy with my breaths from there.