JJCCR and wetsuit diving

[justinthedeeps]

I'm not sure I follow why you would need to swap valves, or O2 clean the dil cylinder. Unless they mean adding different valves that are not inline valves. Regardless, it already seems a bit confusing already.

Many thousands of hours have been done with standard config JJ's in wetsuits, well past 100 metres depth. You can dive it in trim with modifying or inverting the cylinders.

Or get a drysuit

 

[mr_v]

I know this is a "wet suit" thread and the OP is in Philippines. However... If you're set on JJ, what if you try diving in a dry suit? Trilam with very thin undies. It will give you another buoyancy source and help with the trim as you'll be able to move the air into your waist/feet area. The trick is to find a suit that is tailored to your body so that the bubble is just large enough to make a difference in the trim but not too large.

Your trim depends on the system buoyancy center. Your system has two major variables - your body and your diving equipment. Try this - jump into a pool wearing only swim trunks, get into a horizontal position and observe how your body reacts. If your waist/upper legs start sinking, your buoyancy center is low. If that is the case, any unit with a low buoyancy center will exacerbate the problem. You will have to try different options, like diving in a dry suit, inverting the valves, or putting something (e.g., a foam block) into the CCR stand to move the buoyancy center. Deep6 Eddies are good fins, too.

 

[LanceRiley]

Try a less dense fin, like the non-dense version of the Apeks RK3, and a buoyant bootie, like 5mm or even 7mm with a proper thick sole.

I once used a ScubaPro Go fin and just sized it up.

A carbon backplate lightens up the whole rig.

You could also try a 'travel stand' for minor improvement.

Finning technique can keep you trim for drills and deco.
If the deco is easy, over 30 minutes, and bottomless below, I don't mind just relaxing into where things want to be

yes went to a lighter fin. Fourth Element Tech fins is light. lighter than OMS Slipstreams

does the plate help? i mean it's staying at your back? not back to front bias. but i do have an aluminum i should try that

Travel stand... a bit lighter... hmm..

 

[LanceRiley]

I know this is a "wet suit" thread and the OP is in Philippines. However... If you're set on JJ, what if you try diving in a dry suit? Trilam with very thin undies. It will give you another buoyancy source and help with the trim as you'll be able to move the air into your waist/feet area. The trick is to find a suit that is tailored to your body so that the bubble is just large enough to make a difference in the trim but not too large.

Your trim depends on the system buoyancy center. Your system has two major variables - your body and your diving equipment. Try this - jump into a pool wearing only swim trunks, get into a horizontal position and observe how your body reacts. If your waist/upper legs start sinking, your buoyancy center is low. If that is the case, any unit with a low buoyancy center will exacerbate the problem. You will have to try different options, like diving in a dry suit, inverting the valves, or putting something (e.g., a foam block) into the CCR stand to move the buoyancy center. Deep6 Eddies are good fins, too.

Hi, thanks for the reply. Yes there are a few tech divers who dive in drysuits in my areas with just a dryfit shirt underneath. it would work. as Tropical as the PHilippines is. going deeper and doing deco can get cold.

Im at the point where i need to move forward. Drysuit and CCRs. Although its a bit hard to have a drysuit maintained here... has to be shipped off for repairs, although some diveshops have done minor repairs. JJCCR isn't cheap... and i wana be happy with it haven't bought my personal unit yet... Im pretty trim with double tanks and stages.

 

[LanceRiley]

I'm not sure I follow why you would need to swap valves, or O2 clean the dil cylinder. Unless they mean adding different valves that are not inline valves. Regardless, it already seems a bit confusing already.

Many thousands of hours have been done with standard config JJ's in wetsuits, well past 100 metres depth. You can dive it in trim with modifying or inverting the cylinders.

Or get a drysuit

I have a techdiver friend who's ahead of me and yes we seem to have the same weight balance... he has 3 lbs on each shoulder strap using light fins and wetsuit... but perfect with dry suit on....

and yeah.. been thinking about the drysuit... but just $$$$

 

[inquis]

I'm not sure I follow why you would need to swap valves, or O2 clean the dil cylinder. Unless they mean adding different valves that are not inline valves.

Sort of. The OP indicated putting the bottles upright makes the valves "on the wrong side", which I take to mean pointed backwards. From that I infer they are not inline valves. Without buying new valves, that mandates that the valves switch sides. To leave the O2 gas on the original side, it has to use the old dil valve (as it has the required orientation). Therefore, it needs to be O2 clean (if it wasn't already). So either free or minimal expense to move a bunch of weight up top, allowing the lead bricks to go away.

I expect the OP is already overweighted (only a 3mm wetsuit) so eliminating those bricks is good from that standpoint as well.

Then again, perhaps I've misinterpreted what the current setup is.

 

[inquis]

If you're going to switch to a drysuit, that should reduce (perhaps eliminate) the issue without changes to the CCR. (The redundant buoyancy is a really good idea, as well.)

 

[LanceRiley]

If you're going to switch to a drysuit, that should reduce (perhaps eliminate) the issue without changes to the CCR. (The redundant buoyancy is a really good idea, as well.)

yes even with 50m dives on OC... i realize... if there's a wing failure i dont really have a redundancy inflation, well.. i do an smb and a lift bag.

 

[Matan]

Hi i did my TDI Mod1 JJCCR course about a year ago... what bothered me the most was the trim.

I coudnt be trim. i was wearing a 3mm wetsuit. with a lightweight fin (recreational) and it would always attempt to pull me feet down. as in vertical. had to put about 3 lbs of weight on each shoulder strap to keep.. me more or less trim..

so how do you dive with wetsuit? i live in the Philippines..

sounds weird.

1. make sure you switch to carbon backplate - the JJ is heavy enough as it is.
2. weights on your shoulders - remove + not sure how you even do that with the T-pieces.
3. light fins are good if you're heavy.
4. stretch our your arms + bend your knees.

I dive my JJ in factory config with a wetsuit / no suit. I tend to use a carbon cylinder for diluent as well to make the unit even lighter.


Matan.

 

[LanceRiley]

sounds weird.

1. make sure you switch to carbon backplate - the JJ is heavy enough as it is.
2. weights on your shoulders - remove + not sure how you even do that with the T-pieces.
3. light fins are good if you're heavy.
4. stretch our your arms + bend your knees.

I dive my JJ in factory config with a wetsuit / no suit. I tend to use a carbon cylinder for diluent as well to make the unit even lighter.


Matan.

1.) Carbon helps? ok was thinking of titanium or aluminum
2.) yes.. just above the D rings. strapped weights there. t pieces are above collar bone. or top of should er so wont bother.
3.) I went light fins since my hip and legs were singing.... if i let go... id end up standing up
4.) yes.. i stretched out my arms and knees bent. but i can only do so much.. whenever you do work.. your arms goes nearer like managing the dive controllers etc.

i have good trim on doubles..