First pool dive with hp steel 100's horizontal trim issues

[denisegg]

LOL. After I read that it didn't make any sense to me either. I was imagining scenarios where you didn't want the chokers because you were completely removing the tanks to push one in front of you, etc. And I do realize people do those sorts of things, just not my particular desire.

 

[denisegg]

I am intrigued by the exchange, and want to be sure I understand to what the OP is referring.I think, but am by no means certain, that I understand what stano did. A length of static line with a bolt snap attached, is looped around the tank valve, before the reg is attached. The bolt snap is then clipped to a chest/shoulder D-ring. The length of the static line remains fixed, so if you move your chest / shoulder D-ring up, you pull the tank 'up' - toward the diver's head when in a horizontal position. The bungee then loops around the tank valve and pulls it into the chest. In the water, the static line / bolt snap remain attached to the chest / shoulder D-ring. The bungee is wrapped around the tank valve, but nothing is attached to it.Not necessarily. You can disconnect the clips in the water if you want. But, you can also leave them attached, and they do influence the position ('height') of the tank valve. What we may have is a matter of semantics, in terms of what you refer to as a 'choker'. Just for clarity, I don't call these loops a 'choker'. Rather, a 'choker' is what is used to cinch the top bolt snap on the tank rigging close into the neck of the tank valve, so that when the bolt snap is attached, to the bungee, or to the ring on a ring bungee, it holds the tank valve in tight to the body. At least this is what DR refers to as chokers. They can be cinched down, by pulling the end of the strap tight, around the neck of the valve, hence the reference to 'choker'. The static line arrangement, that I think, but am not sure, the OP refers to, does not cinch down.
View attachment 116506

My point is not to agree or disagree with what someone may want to do with their own rig, rather to better understand what the OP means.

I use the clips on the left of the above picture but they are not to hold the tanks in position, my bungee system does that. Their only purpose really is to faciliate donning and doffing the tanks, which would especially be useful in OW from a boat, etc.

 

[stano]

On my rig (JT) the bungee is a loop style that starts and ends on the middle of my back. It does run through a ring on the front straps (at the chest strap point). I am not using the factory Dive Rite bungee. When I attach my bungee I pull a loop around the handle on the valve.

I have seen several connotations of the bungee including the one that starts at the back and simply runs under the arm to front of the harness (i.e. not a loop). What style bungees are you guys using? Pics would be great.

If my bungee ran from the back to the front (i.e. not a loop bungee) I could clearly see how adjusting the cam band only could push the tank forward or backwards. The way mine is rigged it could never work well without the static line as far as I can tell.

Stano



Stano

 

[cavemn]

LOL. I was imagining scenarios where you didn't want the chokers because you were completely removing the tanks to push one in front of you, etc. And I do realize people do those sorts of things, just not my particular desire.

Not yet on the 'no mount' for me. I certainly see the risk in losing a tank that way.

 

[cavemn]

On my rig (JT) the bungee is a loop style that starts and ends on the middle of my back. It does run through a ring on the front straps (at the chest strap point). I am not using the factory Dive Rite bungee. When I attach my bungee I pull a loop around the handle on the valve.

View attachment 116660

Stano

I have the same bungee setup from Edd. The rest of my JT looks very different due to mods I did to relocate straps and move the bag lower on my back for more hip support. I added another knot on one side of each loop to bring the front of my tanks up a bit.

The cam band on the tank can be used to adjust the tank and make it(tank) ride more forward if you are shoulder up or more back if your are hip light(shoulder down). I see most people moving the bands lower on the tank thus pushing the tank more forward. The clip on the leash attached to your cam band will eventually push against the bottom of your rail making the tank ride more forward.

Honestly, I see two issues complicating your setup. The JT likes to collect air at the top which makes anyone shoulder light. Your tanks are short(stubby) and heavy which concentrates the weight in a smaller area. Both issues are helping drive weight to your hip area. Lighter fins will not do much good. I'm not sure what the attraction to the tanks boot might be other than convenient vertical stowage. You should remove them if only to test the bands at the lowest possible point on the tank.

My earlier recommendation still stands. If you remove the tank boots and get that band as low as it can go on the tank, get the JT as low on your back as functionally it can go using the lightest fins for your diving environment and find you still cannot hover in a good horizontal position. It's time to think about swapping the tanks or the Nomad.

 

[stano]

I will take the boot off and see if I can push the tank forward a bit more. I do have the cam band on the boot itself for experimentation only. I would never actually dive like that however. Yes, I have to admit I left it on mostly for convenience.

As per my video I think i am at least in the ball park now. The week before was horrible and frustrating to say the least.

I see that Dive Rite has a "trim pillow" out now. It shows up on their dive rite tv area. It appears that enough people have this issue that they are attempting to "fix" the issue. I like the idea of putting the air closer to the feet exactly where it has the most affect. I suppose if the pillow were used the shoulder weights could likely come off. I may give it a shot if once I get my F1's back the heavy legs come back.

Lots of interesting comments and discussion. Appreciate all the feedback. I am admittedly a rookie working my way through this.

Stano

 

[cavemn]

I see that Dive Rite has a "trim pillow" out now. It shows up on their dive rite tv area. It appears that enough people have this issue that they are attempting to "fix" the issue. I like the idea of putting the air closer to the feet exactly where it has the most affect. I suppose if the pillow were used the shoulder weights could likely come off. I may give it a shot if once I get my F1's back the heavy legs come back.

Stano

Stano,
Please, consider the extra task loading of managing a second and separate buoyancy device over shoulder weights

 

[Dive-aholic]

And, I will admit that I have never done that, nor heard of anyone doing it, nor suggested it to a student. But, if it works for the OP . . . And, they can get kinds 'busy' with the other things that are clipped there, plus moving them might change the ease of access to back-up lights, etc. My take on what the OP has done is that he is trying different ways to adjust his rig to achieve optimal trim. He may try some things that appear to 'work', but have other consequences that make the solution not optimal in the long term. But, at least he is trying different things, and evaluating the outcome in a somewhat methodical manner.

If he had moved the d-rings for that reason then that's a different story, but he said he moved them to adjust the trim of his cylinders. If the cylinders depend on the chest d-rings for their positioning then they are likely hanging too low.

The goal has been to shift his CG 'forward' (toward his head), and he has moved his tanks up and added trim weights that provide a weight 'moment' to facilitate this. One thing he hasn't done yet that cavemn suggested early on is remove the boots, and shift the cam band even lower. As cavemen also mentioned he could also change to pipe clamps which would allow him to move the bottom attachment as far down the tank as possible.

He stated he put the cam bands over the boots. That would allow him to position them even farther down than by removing the boots because the boots are over the curved bottom of the cylinders. If there's still an issue with trim with the cam bands on the boots removing the boots will not fix it.

 

[Dive-aholic]

On my rig (JT) the bungee is a loop style that starts and ends on the middle of my back. It does run through a ring on the front straps (at the chest strap point). I am not using the factory Dive Rite bungee. When I attach my bungee I pull a loop around the handle on the valve.

I have seen several connotations of the bungee including the one that starts at the back and simply runs under the arm to front of the harness (i.e. not a loop). What style bungees are you guys using? Pics would be great.

If my bungee ran from the back to the front (i.e. not a loop bungee) I could clearly see how adjusting the cam band only could push the tank forward or backwards. The way mine is rigged it could never work well without the static line as far as I can tell.

Stano

View attachment 116660

Stano

I use loops. I started using loops long before anyone around here did. You can see photos of the original mods I made to my Nomad on my website. The way I position my cylinders is through the cam bands. This works quite well with the loops. The only reason for the bungee is to keep the valve end of the cylinder tucked up. It has no other function.