CCR Try Dive - old dogs and new tricks

[Graeme Fraser]

So, as a "dyed in the wool" OC diver, I finally succumbed to curiosity and did my first ever CCR try dive yesterday on the VMS Redbare. First observation; what an amazing piece of kit! Second observation; what the hell happened to my buoyancy!

Following a detailed explanation on the magic box we kitted up and entered the confined water section in Vobster Quay for a weight check and to sling a bailout. After that was trim (not too shoddy) and basic buoyancy control (hmmm). We then did some other basic drills including loop management and bailout. Fast forward to our gentle OW dive and wow you suddenly realise how noisy OC divers are!

Although reasonably happy with my trim. I'll admit that buoyancy was driving me nuts. Even though I was venting through my nose, I just couldn't convince my old fart of a brain that normal breath control wasn't going to help. As a result I heavily over breathed, constantly trying to correct, proof of which was the post dive telemetry which grassed me up in great detail. Anyway my instructor (who was brilliant) seemed reasonably happy with my performance, even if I wasn't, although maybe he was just being kind.

The upshot: I enjoyed the occasional sweet spots enough that I'm determined to delve further into the mysterious world of silent diving. Looks like a life of poverty awaits.

 

[rjack321]

That made me laugh in a good way, bravo
Which unit(s) did you try?

 

[Graeme Fraser]

That made me laugh in a good way, bravo
Which unit(s) did you try?

The VMS Redbare VMS - Vobster Marine Systems
Obviously nothing to compare to, but I do know and trust Vobster. I also have a couple of buddies who have recently moved over from the inspiration and rave about it. Although I am a brevver luddite, I was very impressed by the technology and machining quality. One thing I know for sure is that any failings in performance were entirely my own.

 

[scubadada]

Hi @Graeme Fraser

Your post brought back fond memories. In 2007, my son and I did a rebreather experience dive with Divetech in Grand Cayman, while they were still at Cobalt Coast. I dived a Dive Rite O2ptima and my son dived an AP Inspiration Evolution. Our hour plus dive at Turtle Reef was a real blast. I estimate I was neutrally buoyant somewhere between a quarter to a third of the time

Our try rebreather experience was fun and informative. I occasionally dive with CCR divers as buddies in Florida, some familiarity with rebreathers makes the predive check much easier. I encourage others to consider a rebreather experience, whether they have any serious interest or not. Divetech still offers this dive on Grand Cayman at Lighthouse Point

 

[doctormike]

I switched to CCR three years ago at age 54. I love it. Wish I had done it years ago.

It has revitalized my interest in diving. I find it fascinating. I love reading about it, talking about it and learning about it. I like the deco advantage on relatively shallow dives. I like the silence. I like not having to haul around two sets of doubles and deco bottles every weekend for fills. I like how you don't worry about the logistics of wasting helium, and not knowing what to do with your expensive gas when you have a blowout and the next dive is shallower. I even like building it and cleaning it post dive.

Buoyancy is always an issue when you cross over. It gets better.

 

[hroark2112]

First dive on a rebreather is always fun. You go from being totally comfortable in the water to a swimming monkey in one swoop!

Seriously though, it is totally worth it. As embarrassing as it was my first few times, eventually it becomes second nature. Then you can laugh at almost breaking your nose descending the first time!

 

[_Ralph]

My first day on CC was similar. Nothing spectacular like face planting into anything, but always trying to get bigger and bigger breaths in to stop my ever so slow descent... while fully knowing well that that is not helpful in anyway.

After a few minutes, brain clicked over and OKish buoyancy achieved.

Still, every once in a while, i’ll draw a big breath, but that fires the ADV, and gets some extra gas into the loop... big difference from early days with a large loop volume.

First day on my CCR course, still some fine (ie course) tuning (always some fine tuning) getting used to the unit after not being on one for 2+ years...

Actually doing the same next month on a different unit (although i’ve been diving my last CCR now for quite a while, however frequency I can get in the water).


I don’t do as much tec diving as i’d like with it yet, as i’m not in a great location to do such dives (I don’t go for depth for the sake of depth), here in the local waters, you’ll just find colder, darker silt with a strong side of no vis... but knocking out a shallower 2+hr dive in 4C waters is bearable (and any warmer waters feels like the tropics to me)


_R

 

[Graeme Fraser]

My first day on CC was similar. Nothing spectacular like face planting into anything, but always trying to get bigger and bigger breaths in to stop my ever so slow descent... while fully knowing well that that is not helpful in anyway.

After a few minutes, brain clicked over and OKish buoyancy achieved.

Still, every once in a while, i’ll draw a big breath, but that fires the ADV, and gets some extra gas into the loop... big difference from early days with a large loop volume.

First day on my CCR course, still some fine (ie course) tuning (always some fine tuning) getting used to the unit after not being on one for 2+ years...

Actually doing the same next month on a different unit (although i’ve been diving my last CCR now for quite a while, however frequency I can get in the water).


I don’t do as much tec diving as i’d like with it yet, as i’m not in a great location to do such dives (I don’t go for depth for the sake of depth), here in the local waters, you’ll just find colder, darker silt with a strong side of no vis... but knocking out a shallower 2+hr dive in 4C waters is bearable (and any warmer waters feels like the tropics to me)


_R

That's exactly what I was doing, taking bigger breaths and triggering the ADV, then venting like buggery to stop the inevitable ascent. I reckon I burned through more gas on CC than I usually do on OC, which is somewhat ironic. Never mind, just makes me more determined. I refuse to be bettered by an inanimate object!

 

[doctormike]

That's exactly what I was doing, taking bigger breaths and triggering the ADV, then venting like buggery to stop the inevitable ascent. I reckon I burned through more gas on CC than I usually do on OC, which is somewhat ironic. Never mind, just makes me more determined. I refuse to be bettered by an inanimate object!

Yeah, one of the things that I definitely noticed as I put more hours on the unit is improved dil consumption. If I'm not doing a lot of up and down at depth, at this point it's pretty minimal.

 

[Dusty123]

So Two things that helped me was spending a couple hours diving really shallow (15-25ft) since it can be such a pia and the other was diving really overweighted by accident i learned that you can squeeze the bc inflator and get just a trickle rather than just hammering on it which worked fine for oc since close enough is good enough on that. Also if you are diving a single bailout cylinder dont forget to roll a bit more gas to one side of the wing to help level out a bit.