Tropical diving: correct amount of weight versus trim (correct weight distribution)

[Vicko]

80% of my dives were done in cheapo mares gear that is available to rent anywhere in the world. Rover bcd and wetsuit, avanti tre fins and a single 15l steel tank with a weightbelt and at least 4kg extra to give to customers.
I never had trouble getting into close to perfect trim when standing still no matter the gear of the amount of weight I had.

You people are overcomplicating it.

 

[berndo]

80% of my dives were done in cheapo mares gear that is available to rent anywhere in the world. Rover bcd and wetsuit, avanti tre fins and a single 15l steel tank with a weightbelt and at least 4kg extra to give to customers.
I never had trouble getting into close to perfect trim when standing still no matter the gear of the amount of weight I had.

You people are overcomplicating it.

A agree, you can be in perfect trim in a cheapo poodle jacket and full foot fins or even split fins.
IMHO, in most of cases I've seen, whatever the issue is, it's a diver skill issue rather than a gear issue. Assuming people use gear that fits them...
The most common I've seen is people using too much weight.

 

[wetb4igetinthewater]

A agree, you can be in perfect trim in a cheapo poodle jacket and full foot fins or even split fins.
IMHO, in most of cases I've seen, whatever the issue is, it's a diver skill issue rather than a gear issue. Assuming people use gear that fits them...

[Mod edit]There are two things: minimal weight determination to remain at a safety stop with a nearly empty cylinder and weight distribution to remain horizontal effortlessly.

The most common I've seen is people using too much weight.

so, barely being able to hold a safety stop (aluminum cylinder, 2 kg, 3 mil full length wetsuit) sounds like I was using too much weight?

[Mod edit]

center of mass versus center of volume/displacement. [Mod edit]

 

[berndo]

I have great trim. I learned to dive in an area with strong currents. When you are not in perfect trim, you have a pretty big problem getting around. Trimming out is pretty easy when you're not overweight in the water.

[Mod edit]

 

[Vicko]

[Mod edit]You can shift your centre of buoyancy by slightly changing your leg extension and your breathing patterns, both are much more convenient than carrying weight plates or messing with rental equipment on vacation dives.

EDIT: Here's a complete trim fanatic making the same point I am.

 

[wetb4igetinthewater]

You can shift your centre of buoyancy by slightly changing your leg extension and your breathing patterns, both are much more convenient than carrying weight plates or messing with rental equipment on vacation dives.

You think I didn't try those things? I would move my legs and arms in various positions. Even when carrying mininal air in my lungs, eventually my feet would fall.

[Mod edit]

Edit: great video, but not applicable due to completely different configuration/equipment.

 

[JoeTPhilly]

Have you tried moving the air in your wing during the dive? I was having trouble and my instructor had me manage the air bubble in the wing. First time actually listening to the air shifting was enlightening.

 

[wetb4igetinthewater]

Have you tried moving the air in your wing during the dive? I was having trouble and my instructor had me manage the air bubble in the wing. First time actually listening to the air shifting was enlightening.

So for the first configuration (steel tank, high up on my back), I had no weight and because we were so shallow, I was using my lungs to control my depth. So I didn't have any air to move.

In the second day of diving (from a boat), where I had an AL11 and 2 kg total in pockets (couldn't put them elsewhere), I had a slight amount of gas at depth. I did try to have my head down slightly (so the gas would go to the bottom of my BCD). But unfortunately, my feet would still drop when motionless.

Thank you though for bringing up a good point. Now if I misunderstood your idea, please correct me.

 

[JoeTPhilly]

So for the first configuration (steel tank, high up on my back), I had no weight and because we were so shallow, I was using my lungs to control my depth. So I didn't have any air to move.

In the second day of diving (from a boat), where I had an AL11 and 2 kg total in pockets (couldn't put them elsewhere), I had a slight amount of gas at depth. I did try to have my head down slightly (so the gas would go to the bottom of my BCD). But unfortunately, my feet would still drop when motionless.

Thank you though for bringing up a good point. Now if I misunderstood your idea, please correct me.

You understood correctly. Also, I have been arching my back more and have found extending my arms at a different angle helps; not quite 45 degrees but not straight out either. As to weighting, all of my weight is on my back; either with a weighted single tank adapter or weight pouches on the cam straps. Also, tank as low as possible. Here are a couple videos which may help:

 

[wetb4igetinthewater]

You understood correctly. Also, I have been arching my back more and have found extending my arms at a different angle helps; not quite 45 degrees but not straight out either. As to weighting, all of my weight is on my back; either with a weighted single tank adapter or weight pouches on the cam straps. Also, tank as low as possible. Here are a couple videos which may help:

Normally I travel with my 5 mil, a SS BP & STA, neutral fins, and I trim out nicely not needing any extra weight. I'll be headed to Panama next year about this time, and will get in some diving. I may opt to resume carrying my gear, as I get most of it in a carry on. I was really trying to travel light in Cuba. I may pack some extra trim pockets. On the first day with the steel tank, I did ask one of the divers if he'd like a tip as his tank was really low. I advised him to raise it and he said it helped a fair bit. He (and I) were still foot heavy, but it was better than before for him.

I think that if I cannot travel with my gear, I'll take some bungee cord to attach weights higher up on my strap. Diving with bent legs is the norm for me, but let's say extending my arms is all that I need. I want to take some pictures, so that isn't the best option (for me).