Trim Pockets? Why do people use them?

[Antagonist]

I am not sure why people use trim pockets around the tank. What do they do? Can someone enlighten me please? Also what does it mean when people adjust their trim. I am new to diving with only 23 dives under my belt. Just curious

 

[mk706]

When diving my Scubapro Knighthawk and and Al80 tank I use about 2lbs per trim pocket. Oddly enough, use to get into trim. The extra weight at the tank counters buoyancy allowing the tank to level, get my head back and up and straighten out the legs.

It's all about getting into a good diving position.

 

[TartanFrog]

I use trim pockets around my upper tank band. I took a bouyancy class a while back and the instructor noticed that although i was okay at bouyancy i was feet down most of the time. He took some of the weight from my belt and moved it up to the top tank band. I immediately leveled out in the water and started using less air. So now I use some weight on either side of the upper tank band.

Not sure if it helps other divers, but it has helped me to stay level and use less air. It also keeps my fins farther away from the bottom. In my mind both of those are good reasons.

 

[The Kraken]

For trim.

The body, when geared up and in the water column is not unlike a teeter-totter, or see-saw, if you will.

Weight distribution will cause the diver, when neutral in the water column, to be either head low or head high. On the rare occasion, a diver will have a naturally, perfectly balanced rig.

Taking part of the weight required for the rig and moving toward the diver's head will make the diver's head lower in the water column. Conversely, if that weight is shifted toward the feet, it will cause the diver's feet to go lower in the water column. Once the trim weights are distributed properly, the diver's body will be horizontal in the water column reducing the inherent drag while swimming and allow the diver to dive more efficiently, using less breathing gas and so forth.

Many divers, although they think that they are horizontal in the water column, are swimming in a head high attitude.

Trim is one reason that it's so important always to mount one's tank in the same position each time; failure to do so will cause a shift in your trim, all other things being equal.

the K

 

[Garrobo]

I am leg heavy which causes me to have a tendency to go vertical in the water if I remain stationerey. I put a couple of three-pounders on the upper part of my backplate to counteract this and remain horizontal in the water. If the operator insists that I wear a BCD instead of a horsecollar I put the weights as high as I can get them depending on what type of pockets it has and where they are located.

 

[The Kraken]

Keep in mind also that this applies not only to one's longitudinal trim but also to one's latitudinal trim.

the K

 

[The Chairman]

The trim pockets will also reduce the amount of ditchable weight a diver needs to carry. If you have more than fifteen pounds around your waist, losing your weight belt can be scary. Yes, you want to become lighter if you do it on purpose, but you don't want to become an ICBM if it happens by accident.

 

[knowone]

Trim, was something I used to adjust with a wheel
when folks let me take the controls of an aeroplane

Then around the time the wheels fell off the Y2K phenomenon
and the momentum of integrated weights seemed to level out
and whilst now it seems the fashion, is to lose so much weight
quickly almost dangerously with no chance of holding any stop
little pockets started appearing everywhere from nowhere trim
they call it because bodies aren't built the same any more and
a torch doesn't weigh enough because holding correct, healthy
posture to glide most effortlessly, at the correct plane through
aqua is being made powers that be, far more difficult than it is

In other words, even with little bits of weight stuck around the
place, only a striving for correct technique will provide the only
tool that's required to get where you are going pushing as little
aqua ahead of you as is possible without having to scratch your
head rubbing your empty pocket wondering which of the means
you will concentrate on like it was, not because when it was like
that the stuff wasn't there to use or buy it just was not required

:goingdown: A diver going somewhere?

This guy's about right so as not to accrue that b/t you don't want

 

[a22shady]

As others have said most who use trim weights will use them and move them around to counter act how there bodies act in the water. I also use trim weights for this and Becuase I do not wear a weight belt or weight pockets. So I use these to keep room free on BP/W. So technically I do not dive with any ditchable weight. I leave my harness clear for my can light or Pony bottle, I personally do not like weight belts so this was a great option for me.

I do dive with redundant bouyancy though so if I have a BC failure I do not need to drop weights I can use my drysuit, or SMB.