Jet Fin Light
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I disagree about it not being an equipment issue.
I have my tank has high as possible without hitting my head (actually do sometimes), have all my weight equalized from side to side and dive with the same posture as the video. I have Twin Jets now and have tried Mares paddle fins. I am still looking. I switched to 7 mm booties to help.
If I am perfectly still with a tank (steel) with more than 700 psi, my feet will sink. In fact I have added tanks weights around the neck and still sink feet first. I have a friend who is DIR and he has gone underwater with me and worked his DIR magic and he is perplexed also. He had me get in the perfect DIR position (he held me there to ensure this) and had me close my eyes and let me go. I slowly sank feet first. And before you ask...yes the BC was totally empty.
Yes maybe I am a
but I am thinking of Twin Jet Max, of Apollo Bio Fins in Yellow or White.
I have tried some other fins like these and the sinking is not as bad. I dive with a Ranger BC.
Standing by for the flames.
I have my tank has high as possible without hitting my head (actually do sometimes), have all my weight equalized from side to side and dive with the same posture as the video. I have Twin Jets now and have tried Mares paddle fins. I am still looking. I switched to 7 mm booties to help.
If I am perfectly still with a tank (steel) with more than 700 psi, my feet will sink. In fact I have added tanks weights around the neck and still sink feet first. I have a friend who is DIR and he has gone underwater with me and worked his DIR magic and he is perplexed also. He had me get in the perfect DIR position (he held me there to ensure this) and had me close my eyes and let me go. I slowly sank feet first. And before you ask...yes the BC was totally empty.
Yes maybe I am a
but I am thinking of Twin Jet Max, of Apollo Bio Fins in Yellow or White.I have tried some other fins like these and the sinking is not as bad. I dive with a Ranger BC.
Standing by for the flames.
I don't understand ... How can trim not be equipment, if your not moving, then how does technique change it?
Equipment ... move it, change it, or add to it
search threads for OMS Slipstreams, they are much lighter than Jets
Equipment ... move it, change it, or add to it
search threads for OMS Slipstreams, they are much lighter than Jets
Aside from technique and equipment, you need to consider where you are distributing your weight. Think of your body as a balance board under water, with your center of gravity as the fulcrum. If your weight is biased below the center of gravity, you will be foot heavy. If it is biased above the center of gravity, you will be head heavy. The further away from the Cg the weight is situated, the greater the leverage it will have over your trim. So, assuming you are properly weighted to begin with, you have a few options:
- Work on your technique to best fit your configuration. Keep in mind that the bouyant parts of your body also effect the Cg. Depending on what you are wearing, you can effect trim by extending/ retracting your arms/legs. That being said, you want to get configured so you can swim in nuetral position so you leave room to adjust for more bottles, or changes in trim as you breathe down a tank. You can only take this so far before you need to change your config. (Cost- $0)
- Redistribute the wieght you are carrying to address the bias (e.g. weight off the belt and into trim locations higher on the body, like the tank strap). Try to get to the point where you can maintain trim w/ minimal input. (Cost- $0- minimal)
- If all else fails, you can look at the equipment. Things like fins tend to have a larger effect on trim since they are so far away from the Cg and have more leverage against Cg. So while there are certainly other ways to address the issue, equipment can help improve the baseline considerably (Cost- much higher)
- Work on your technique to best fit your configuration. Keep in mind that the bouyant parts of your body also effect the Cg. Depending on what you are wearing, you can effect trim by extending/ retracting your arms/legs. That being said, you want to get configured so you can swim in nuetral position so you leave room to adjust for more bottles, or changes in trim as you breathe down a tank. You can only take this so far before you need to change your config. (Cost- $0)
- Redistribute the wieght you are carrying to address the bias (e.g. weight off the belt and into trim locations higher on the body, like the tank strap). Try to get to the point where you can maintain trim w/ minimal input. (Cost- $0- minimal)
- If all else fails, you can look at the equipment. Things like fins tend to have a larger effect on trim since they are so far away from the Cg and have more leverage against Cg. So while there are certainly other ways to address the issue, equipment can help improve the baseline considerably (Cost- much higher)
You are probably correct and I didn't express it properly also. My point is that it seems that no matter what equipment I use or where the weights are located...I sink feet first.
I am grasping for answers myself and switching to 7 mm booties to add some buoyancy helped so now I am searching for the "perfect" fin to even things out.
I am grasping for answers myself and switching to 7 mm booties to add some buoyancy helped so now I am searching for the "perfect" fin to even things out.
I can feel your pain. Everyone who has ever tried to perfect their buoyancy has gone through some stage where they are feet heavy/light, or some other issue, and spent a lot of time and effort trying to correct it. A couple years back I tried to tune in exactly how much weight I carried in different locations. I repositioned tanks, etc, and finally found this balance where I could acheive "perfect" weighting, but it was only with the tank at a certain pressure, and during other times in the dive, the hover motionless thing just didn't work.
Then, a funny thing happened--I started diving more and more, and started finding that I could dive just fine, and maintain whatever trim I wanted in configurations where I couldn't satisfactorily maintain my trim before. There are subtle little things you learn to do to keep your feet in the right position: bending or straightening your legs, adjusting your arms, head and upper body, and slowly sculling your fins.
In the video, the diver was moving his fins even when he was perfectly stable in the water. He probably didn't even realize he was doing this, but it's an unconscious adjustment you learn to make when you start gaining experience. I can't say exactly why, but in time, you just learn to deal with your buoyancy and weighting even when they aren't perfect.
Tom
Then, a funny thing happened--I started diving more and more, and started finding that I could dive just fine, and maintain whatever trim I wanted in configurations where I couldn't satisfactorily maintain my trim before. There are subtle little things you learn to do to keep your feet in the right position: bending or straightening your legs, adjusting your arms, head and upper body, and slowly sculling your fins.
In the video, the diver was moving his fins even when he was perfectly stable in the water. He probably didn't even realize he was doing this, but it's an unconscious adjustment you learn to make when you start gaining experience. I can't say exactly why, but in time, you just learn to deal with your buoyancy and weighting even when they aren't perfect.
Tom
I agree totally with this. I am SO much better now but I finally was able to get comfortable one day with my BC cinched up a certain way. It is frustrating though to be hanging with some guys that just are motionless and I am having to scull to stay in the same position.
A buddy video taped me once and what I thought was horizontal was actually head down. I am definitely not a DIR guy but I like their dive position in the water.
A buddy video taped me once and what I thought was horizontal was actually head down. I am definitely not a DIR guy but I like their dive position in the water.
SparticleBrane
Contributor
I am under the impression that was Andrew Georgitsis in the video (could be wrong) and if it is, I'm fairly certain he's experienced enough to know he was moving his fins.
That video was filmed in the Red Sea...no one can stay perfectly still where there is moving water, if you want to hold position.
Everyone is going on and on and on about weight distribution, and how many pounds you have here, and how many there, and tank up or down...yes that makes a small difference, but the biggest difference you'll find is technique. After that, fix the small details.
I have yet to come across an equipment configuration that would not allow me to stay in trim. Doubles -- big or small, singles -- big or small, doubles + stages/deco cylinders, no tanks at all, lots of weight on one side with none on the other....it's all about body position and technique.
On one specific dive I remember going around gathering up ~15lbs of weight after using them to mark some locations (long story) and after putting all the weight on one side of my harness while swimming back to the dock, I could still stay in pretty good flat trim. Not bragging...just saying it can be done.
AggieDad -- clench your butt muscles and arch your back. That will help put you into the correct position. Over time you won't have to do that to stay in trim, but it helps with the feeling initially.
AggieDad -- clench your butt muscles and arch your back. That will help put you into the correct position. Over time you won't have to do that to stay in trim, but it helps with the feeling initially.
I saw a picture the other day expressing just that fact and tried it. It did help tremendously. I am pretty close to getting it zeroed in for all my usual configurations. I always carry six lbs of soft weights when helping with students and can give them some or pick up some and still maintain trim. It is when I get distracted and get out of position for a while that I realize that I have reverted back to my "normal" position in the water.
I saw a picture the other day expressing just that fact and tried it. It did help tremendously. I am pretty close to getting it zeroed in for all my usual configurations. I always carry six lbs of soft weights when helping with students and can give them some or pick up some and still maintain trim. It is when I get distracted and get out of position for a while that I realize that I have reverted back to my "normal" position in the water.
If you are diving a properly adjusted and weighted rig then maybe this statement is correct. And once you understand how trim and bouyancy works then yes, you can trim out in just about anything. But setting up the equipment properly, weighting and distributing weight properly puts you in the best position to learn the skills to get you there. What's you understand what's going on, then the things you mention become easy to do.
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