DIR- Generic Carbon plates and Al plates and trim

[ginti]

The tail weight is there for trim. Otherwise i flip over.

If this is the case, maybe alu plate + tail would give you the right weight + right trim. However, I am curious: without tail, do you flip over just at the end of the dive, or always, or only at the beginning?

 

[LanceRiley]

If this is the case, maybe alu plate + tail would give you the right weight + right trim. However, I am curious: without tail, do you flip over just at the end of the dive, or always, or only at the beginning?

I flip over at around 120 bar.

 

[LanceRiley]

It does sound like you are overweight. If you change from steel to Ali/carb plate, you will help reduce that excess weight. But your trim will also change a bit. Last year I changed from a steel to Ali plate because my trim was impacted by being very head heavy. The ali plate with a light tail weight helped me achieve a better trim.

You will simply have to reevaluate your trim and any weight placement again, but it shouldn't be hard!

There was a nice post not long ago about achieving neutral trim: Fixing diver trim and weight placement

This is what i thought i would do.

I already have an alu plate. And yes im head heavy.

By making myself backplate light…. Hoping to make myself a bit feet heavy with tail weight

 

[ginti]

I flip over at around 120 bar.

I imagine you have already tried different positions for the tanks, higher or lower on your back, right?

PS A slight change in trim with alu tanks is normal, but it is usually so little that people can counteract with proper finning techniques

 

[LanceRiley]

I imagine you have already tried different positions for the tanks, higher or lower on your back, right?

PS A slight change in trim with alu tanks is normal, but it is usually so little that people can counteract with proper finning techniques

Yes. Tank band to the highest point in the tank and shoulder strap lengthened such that the tank sits lowwer in the bank. Approxtank valves shoulder level. If im standing and your looking straight at me… you can barely see the tank knobs peeking above my shoulders

 

[ginti]

Yes. Tank band to the highest point in the tank and shoulder strap lengthened such that the tank sits lowwer in the bank. Approxtank valves shoulder level. If im standing and your looking straight at me… you can barely see the tank knobs peeking above my shoulders

Got it.

Quick thoughts:
- aluminium tanks change their buoyancy AND trim over the dive; this is jut physics
- the tail weight does NOT change the above mechanism, you are only more feet heavy at the beginning of the dive, and more at the end of the dive
- being overweighted may exaggerate the problem (you have air in your wing -> your legs go slightly up -> air goes to the bottom of the wing, which now is slightly higher -> you are now even more head-heavy); being overweighted ALWAYS exaggerates problems
- most likely, it's just a matter of getting comfortable; however... As long as you are balanced I see no problem, and the aluminium/carbon plates are even nicer to travel

I would go for it, but I would keep in mind that, once comfortable, I woud first try to remove weight, then try to use other weight distribution just to see what happens.

 

[inquis]

aluminium tanks change their buoyancy AND trim over the dive; this is jut physics

I think it's more accurate to say the tank (both AL and steel) loses mass during the dive. How that impacts trim depends on the rest of the setup.

Ideally, one should first arrange to be in trim with nearly empty tanks & wing. Add/subtract/shift ballast as required. (This also ensures one is not overweight.) As a second step, position the wing to be in trim with a full tank without moving any lead. If this is done, there will be no change in trim throughout the dive. (The wing lift and additional gas mass remain aligned throughout.)

 

[LanceRiley]

Got it.

Quick thoughts:
- aluminium tanks change their buoyancy AND trim over the dive; this is jut physics
- the tail weight does NOT change the above mechanism, you are only more feet heavy at the beginning of the dive, and more at the end of the dive
- being overweighted may exaggerate the problem (you have air in your wing -> your legs go slightly up -> air goes to the bottom of the wing, which now is slightly higher -> you are now even more head-heavy); being overweighted ALWAYS exaggerates problems
- most likely, it's just a matter of getting comfortable; however... As long as you are balanced I see no problem, and the aluminium/carbon plates are even nicer to travel

I would go for it, but I would keep in mind that, once comfortable, I woud first try to remove weight, then try to use other weight distribution just to see what happens.

Just curious…. Would the halcyon legend wing help? Its suppose to be better on top heavy divers?

 

[ginti]

Just curious…. Would the halcyon legend wing help? Its suppose to be better on top heavy divers?

No clue - but honestly I would be surprised if it does