Info Helium is expensive and deep air is not my thing. -Let's talk about "Big" dives.

[LI-er]

...

 

[grantmac]

Anyone feel like we're training an AI here?

 

[BoltSnap]

Anyone feel like we're training an AI here?

Be careful, my prior post about ASD was deleted.

 

[justinthedeeps]

Still waiting for the "is this a bot" Reaction to come online

Dat traffic generation tho

 

[PfcAJ]

Be careful, my prior post about ASD was deleted.

I got a mod peepee slap on one of the original ASD threads about AI.

Don’t get in the way of add revenue.

 

[Wibble]

How can I plan these two dives theoretically speaking?

Do basic training, often called "Open Water". All agencies will teach you planning to NDL (no deco limits). They'll even give you a dive planner.

This info you have graciously provided is your personal experience? Are there technical instructors who have dived twice a day to these depths?

40m/130ft isn't deep.

You need training though. And practice, lots of practice.

 

[NothingClever]

Here are some things we can I do with Nitrox to practice for the BIG dive.

I went ahead and turned on track changes.

 

[NothingClever]

Very educational but it’s still imperative I talk through sections which I’m confused about or don’t fully understand with those who wish to do so.

I’m a motorcycle nerd. I manage a race team in MotoAmerica (motorcycle road racing), I’m an Advanced Training Program instructor with the largest motorcycle track club on America’s east coast and I also periodically instruct with Yamaha Champions Riding School, one of America’s two most dominant schools staffed with some of America’s best racers.

If somebody who didn’t know how to ride a motorcycle showed up in those circles and started asking questions, I’d entertain a few questions for a minute or so. After that I’m going to point them towards finding some basic training how to operate the motorcycle. Otherwise I’m wasting both of our time talking about more advanced techniques the beginning rider (not even Novice class) isn’t ready to implement.

Same principle applies here. Go get certified on how to do basic SCUBA diving and let’s stop wasting each other’s time in the Technical Forum. If you want to maintain that you must learn about technical diving to get ready for a basic SCUBA course, then pick up an intro to technical diving course manual and read it, take notes in the margins, call your local dive shop, etc.

Good luck with your OW course and I hope you enjoy applying yourself there.

 

[Wibble]

@Learner Diver - you seem to have done a spate of "disagree" reactions to a few posts where experienced divers speak about their own diving knowledge and experience.

"We" are all taking your posts at face value: you're presenting as someone with no scuba knowledge and we're replying in a similar vein.

This is a technical forum where advanced scuba issues are discussed and knowledge shared by experienced divers. You appear to not meet the minimum requirements.

You can plan two dives to 40meters for 40 minutes in a day with a 3 hour surface interval.
The OTU should be below 300 and %CNS should be below 70% on air with 50% and 80% deco gasses.
Your second dive will have a much longer decompression obligation and the gas plan should account for that.
But, I am an idiot on the internet and you should learn to plan consecutive deco dives from a proper instructor.

How can I plan these two dives theoretically speaking?

Do basic training, often called "Open Water". All agencies will teach you planning to NDL (no deco limits). They'll even give you a dive planner.

This info you have graciously provided is your personal experience? Are there technical instructors who have dived twice a day to these depths?

40m/130ft isn't deep.

You need training though. And practice, lots of practice.

As "we" have all said, you need to learn these techniques. Even signing up for any agency's basic diving course will give you access to the information on dive planning. As a novice, this will be strictly limited to No-Decompression Limits (NDL) diving at shallow depths. Going deeper without the appropriate skills and knowledge is dangerous, hence the information isn't readily available outside of a course.

Diving is not all about theory; the practical side is critical. You must build your skills as you progress. The sea is littered with the corpses of people who did not have the skills nor attitude to dive safely.

To join them, get MultiDeco for planning, strap on an oxygen tank and go diving. Or get trained to work out the fallacy.

 

[Alex Ouroboros]

Why are you assuming this does not include CCR?
- You should do the shallower practice dives on the CCR too.
- With bailout like you are going to 100m
- Entering and exiting the water with all the gear on your own.
- Sitting at 3-6 meters with the rebreather for 30 minutes
- and so on

But, this is not the rebreather forum and more importantly - I have not done the jump to CCR yet. (Does anyone have a spare $8k lying around?)
My math for CCR is 30 to 1
At $8,000-$10,000 (Unit + training) the number of big dives you would need to break even is about 30.
This comes out to a big dive every other week for a year.
I think CCR is the way to go for my future.
CCR can be a bit too much for some, especially if you do ~10 big dives a year. The hassle of flying with the unit and getting service and sorb when you land makes the logistics more complicated.

Units are getting more reliable. The systems are getting easier to use and maintain. I predict a future where CCR rental is as common as Twinsets and stages are today. Liveaboards will have units available for traveling divers.
But we are not there yet.

For now, us peasants are still using OC and rubbing sticks together to make fire
My opinion is that you can do the Non-Helium dives with the same configuration as big dives and it will make for a fun and higher quality experience when you do pay the big bucks for Trimix fills.

my best advice here with regard your reasoning and math(s) is aim for a freshly serviced 2nd hand JJ it won’t cost as much as you think and is definitely the best bang for buck imo, (actually they’re fantastic)
And what you would find is you’d use it almost all the time, I understand your calculations about the number of big dives required to warrant it, but it doesn’t actually work like that, you would get far more higher quality dives out of it from the point of view of bottom time,
45min at 30m on air would cost 7min of deco for the same on 28% nitrox on OC its nearly half an hour,, and the twinset then needs a refill, the ccr has got at least another full dive in it probably 3…

Hope this helps you see the extra benefits,, and once you involve a blast of helium it’s a bigger win