Regs for Deco/Stage Bottle

[nereas]

In general I prefer to use flow by unbalanced piston regs for my deco bottles for the follwoing reasons:

1. Super simple - 1 moving part and only 2 dynamic o-rings, both of which are in the IP section of the reg.

2. There is no HP air past the seat, which keeps the PO2 to which all the o-rings (except the HP port o-ring and the DIN retainer o-ring) are exposed to as low as possible.

3. Unbalanced - the inhalation effort rises noticeably when the tank pressure falls below about 350 psi, so you never get surprised whena deco bottle suddenly goes dry. With a balanced first stage you can literally not notice when you use the last full breath so when you exhale, you may get a rude surprise when there is nothing there. A little early warning ensures you can do the gas switch smoothly and with no surprises.

4. The design is bullet proof and will survive a flooding or a swap from one tank to another under water (although you will need to take it apart and rinse and dry it out afterword.

5. Regs in this class like the Scubapro MK 2, Mk 3, Mk 200 and the USD Calypso are lightweight and low profile and work well in terms of hose routing on a deco tank.

6. 70' is not that deep for even a flow by piston first stage and the 90 or so SCFM available from a reg like the Scubapro Mk 2 is more than enough.

Personally I use MK 3's and Mk 200's which have the benefit of being easy to service, readily available, and inexpensive to buy even in excellent condition.

For a reg used for travel gas or deep deco bottle with 36% I prefer to use a Mk 17. It offers more than enough performance to be used even on the bottom yet is still compact and with decent hose routing for a deco bottle.

I also switched from Mk 25's to Mk 17's for my back gas.

I love reading your posts, DA, because I learn something new every time I do!

 

[CompuDude]

I went with ScubaPro exclusively simply because the 2 best gear technicians at the 2 best tech stores where I live are ScubaPro experts. And they are also the people who first suggested to me that your O2 bottle and your argon bottle do not need exclusive high performance regs.

In your area, with Tobin, you could go feasibly with any set of regs that he is good at repairing. I am guessing he can do anything. He is very well known, both among his friends as well as among his enemies.

I have 2 of Tobin's backplates myself, so he is in my friend category.

To answer your question directly, probably any reg works fine at 20 fsw. How could it not? That is practically a swimming pool depth!

I wasn't aware Tobin does reg service in addition to his many other skills. LOL Good to know.

I am fortunate enough to be very near a fantastic ScubaPro tech with 20+ years of experience, and his ONLY job is servicing regs, so he is a real local resource. He handles my primary regs servicing needs, so ScubaPro is a real consideration for that reason. As it happens, he's also certified for AquaLung (and I'm sure he's just as good with AL as he is with SP), so there's no real service issue either way for me.

I'm not going to be servicing my own regs any time soon, so one way or the other they'd be going to him.

I think I'll go low-end to start. It'll certainly meet any needs I may have while training and preparing... when I start doing serious dives, I'll probably upgrade, but $100 for the Calypso will get me started a lot sooner than waiting until I have $600 or so set aside for more high end ScubaPro regs. Heck, the difference in cost will pay for the training!

 

[nereas]

I ... am fortunate enough to be very near a fantastic ScubaPro tech with 20+ years of experience, and his ONLY job is servicing regs, so he is a real local resource. He handles my primary regs servicing needs, so ScubaPro is a real consideration for that reason. As it happens, he's also certified for AquaLung (and I'm sure he's just as good with AL as he is with SP), so there's no real service issue either way for me.

I'm not going to be servicing my own regs any time soon, so one way or the other they'd be going to him.

I think I'll go low-end to start. It'll certainly meet any needs I may have while training and preparing... when I start doing serious dives, I'll probably upgrade, but $100 for the Calypso will get me started a lot sooner than waiting until I have $600 or so set aside for more high end ScubaPro regs. Heck, the difference in cost will pay for the training!

I worry about what I am going to do in the future when my ScubaPro service experts grow old and retire. With 7 first stages and 6 seconds, that is a lot of maintenance work. That is just one of the issues of gearing up for tech and choosing a brand of product.

You seem like the kind of diver who will relish tech training. It takes you all the way out to the edge of the frontier of scuba. You will write dive plans beyond anything you ever dreamed of before, and then actually go dive them. And you will then probably eventually start to wonder about closed circuit as well.

Some people go into closed circuit early on. If you end up doing this, it extends your range into the closed circuit realm of diving which is beyond open circuit, and it saves you about $7,500 in open circuit purchases. I am not necessarily recommending that, however you may want to consider it, depending on what your ultimate plans and goals are. I myself have no plans or goals for CCR diving. There are others here who can advise you better than I can on CCRs.

Take a look a V-Planner early on, for software. Chickdiver (in Florida) recommended that to me a couple of years ago, and it is the best advice anyone has ever given me for tech.

 

[rockjock3]

"Standard deco gas."

No such thing on Earth, if your instructor taught you how to think for yourself.

Get a copy of V-Planner and play with it, and it will teach you that there are many options that are far superior to anything currently labelled as "standard deco gas."

Technical anything (including diving) is a lot like the scene in Pirates 1, where Johnny Depp as Capt Jack Sparrow explains to Orlando Bloom as Will Turner, "The only rules that matter are these -- what a man can do, and what a man cannot do. Now me, I can let you drown, but I cannot bring this ship into Tortugas all by me one-sie. And you, you can either accept that your father was a pirate and a good man, or you can't, but you will have to square with that yourself one day, because pirate is in your blood, boy."

If there ever was such a thing as "standard deco gas" and no pirates, then we would all still be breathing EAN 80 and EAN 36 because of someone like yourself insisting that it was standard deco gas. Make sense?

That makes sense, and I never said "standarnd' meant "only" as you seems to take it. I know you can use a multitude of gases depending upon your profile, but there are "standard gases" that many of the tech agencies teach as that starting point. There are also standard deco depths that are taught. That is why I was curious as to where the 140' and 30/30 came from. I was curious as to if it was an agency specific thing or a you and/or your area's divers' thing. I was simply asking to try and exand my current knowledge base and maybe learn some more.

 

[rockjock3]

"Standard deco gas."

No such thing on Earth, if your instructor taught you how to think for yourself.

Get a copy of V-Planner and play with it, and it will teach you that there are many options that are far superior to anything currently labelled as "standard deco gas."

Technical anything (including diving) is a lot like the scene in Pirates 1, where Johnny Depp as Capt Jack Sparrow explains to Orlando Bloom as Will Turner, "The only rules that matter are these -- what a man can do, and what a man cannot do. Now me, I can let you drown, but I cannot bring this ship into Tortugas all by me one-sie. And you, you can either accept that your father was a pirate and a good man, or you can't, but you will have to square with that yourself one day, because pirate is in your blood, boy."

If there ever was such a thing as "standard deco gas" and no pirates, then we would all still be breathing EAN 80 and EAN 36 because of someone like yourself insisting that it was standard deco gas. Make sense?

That makes sense, and I never said "standarnd' meant "only" as you seems to take it. I know you can use a multitude of gases depending upon your profile, but there are "standard gases" that many of the tech agencies teach as that starting point. There are also standard deco depths that are taught. That is why I was curious as to where the 140' and 30/30 came from. I was curious as to if it was an agency specific thing or a you and/or your area's divers' thing. I was simply asking to try and expand my current knowledge base and maybe learn some more.

 

[nereas]

That makes sense, and I never said "standarnd' meant "only" as you seems to take it. I know you can use a multitude of gases depending upon your profile, but there are "standard gases" that many of the tech agencies teach as that starting point. There are also standard deco depths that are taught. That is why I was curious as to where the 140' and 30/30 came from. I was curious as to if it was an agency specific thing or a you and/or your area's divers' thing. I was simply asking to try and expand my current knowledge base and maybe learn some more.

Indeed, you can use a multitude of gases depending upon your profile.

And you should choose those gasses that maximize your decompression efficiency, in my opinion, and in the opinions of those who taught me. One of the two instructors really harped on this a lot. And in his spare time he used to tell us a lot of GI3 jokes!

The agency and the two tech instructors that I certified with first spoon fed us deco tables and gasses and procedures, then dived us gradually to 250 fsw, then cut us loose with our C-cards to plan our own dives based on the following general principles, at least this is what I got out of it, and what I can remember off the top of my head:

1) Customize your MOD mix and each of your deep deco mixes as needed to optimize decompression for each of your planned MODs;

2) Plan conservatively;

3) Always test your own gas fractions (this is basic);

4) Work up gradually each dive season to the profiles that are relevant to our stated objectives, not all at once;

5) Pay attention to our own body's reactions to what we are doing, and modify subsequent profiles accordingly;

6) Stay within safety margins for Ox Tox exposure;

7) Evaluate and minimize all risks;

8) Plan redundancy for each stage of decompression;

9) Use the buddy system but never become buddy dependent;

10) Get your gear serviced regularly (this is also basic);

11) Maintain regular physical fitness (this is basic as well);

12) Stay current on the latest findings in the dive literature.

It's no deep secret what agency I got my certifications through so you only need to read my profile. I believe the instructor(s) that you choose are more important than the agency however.

I recoiled away from instructors and agencies that tried to teach that there is only one orthodox way of doing anything. I gravitated towards instructors that emphasized thinking and customization.

And I have some pretty good GI3 jokes now too!

 

[CompuDude]

That makes sense, and I never said "standarnd' meant "only" as you seems to take it. I know you can use a multitude of gases depending upon your profile, but there are "standard gases" that many of the tech agencies teach as that starting point. There are also standard deco depths that are taught. That is why I was curious as to where the 140' and 30/30 came from. I was curious as to if it was an agency specific thing or a you and/or your area's divers' thing. I was simply asking to try and exand my current knowledge base and maybe learn some more.

I'm not certain about the 140' thing, but I'm pretty darn sure that 30/30 is GUE's standard trimix mix, for better or worse...

 

[Tom Winters]

It's way easier to standardize your regs across the board.

 

[Rainer]

I'm not certain about the 140' thing, but I'm pretty darn sure that 30/30 is GUE's standard trimix mix, for better or worse...

It's "A" GUE standard mix, certainly not the only one! That said, the few GUE Tech 1 divers I know don't bother with it (most prefer either 21/35 or simply 32% for the relevant depths).

In any case, what deco classes are you training for that require you to sling a 40 at this point?

 

[nereas]

It's way easier to standardize your regs across the board.

I completely agree.

Thats why mine are all ScubaPro. And also why mine are all O2 cleaned, except for the argon bottle Mark 2.