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I went DIR... but my bungies pulled me back!
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Discussion Starter · #1 ·
I'm just at the point where I want to  push myself a bit more when diving and start to do some planned deco dives.  At the moment I dive a single + pony with a BC.  So I need to spend a bit of money getting the right kit, wing, BP twins etc.  There is a fair bit of money to be spent to get the right kit.  Someone suggested a rebreather would be a better bet.  I have done some internet searching and found lots about the different options out there, but what a would like to know is how much does a rebreather cost to run, eg servicing, scrubber and such.

Also is there much advantage in using an SCR over OC for dives in the 30 - 40 mtr range, and as there is not much difference in cost of an SCR with an O2 monitor compared to a CCR, is it best just to find the little bit extra cash and go CCR straight off.

Any advice would be very helpfull.

Cheers all

Darren
 

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Charter Boat Skipper, Salvage Diver & YBOD abuser
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<font color='#000080'>Darren,
Top of page 2 on this forum- Rebreathers : costs involved

Hope you're simulating deco-dives on your no-stops already-
bouyancy, reg-switches, SMB deployment etc.....well worth the effort  in a low-risk situation.

I,m into my 3rd year on the YBOD but do very little deco on it- one of the big advantages of a CCR... do the deco-dives I used to but without the stops  

e.g. : OC- [email protected] 25m = 20mins stops
       CCR   [email protected] 25m = 1 mins    "
         "      [email protected] 25m = 18 mins  "

Just choose your option!
If you ever get into trimix the savings on gas are incredible.
ATB,
Terry
 

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Just not enough dive time.
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Please explain, the tables I have read 25mind for 25mtrs to be inside NDL.
How do you get 60mins at that depth with no stops.

Matt
 

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That's Dude with an E
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Hey Scotty.
I find most of your posts interesting, however criticising what someone has posted and then not clarifying is just not cricket.

Matt
What, I assume, Scotty should have stated is OC on 40% eanx and Terry OC on air.
 

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[b said:
Quote[/b] ] however criticising what someone has posted and then not clarifying is just not cricket.
I'm playing by the same rules as Terry. Incomplete (being generous here) and unjustified statements maskerading as fact. If you want to offer advice or comparisons then be honest when you do so. State assumptions and give enough data so that others can see how you've arrived at your conclusions

[b said:
Quote[/b] ]How do you get 60mins at that depth with no stops.
Using VPlanner, actually get over 70 minutes with no stop

Using Zh16 and my usual GF factors I get 80 minutes @ 25m with 1m stop (EAN40)

[Would I dive those plans? No. Adding a safety stop costs very little.]

Scotty
 

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[b said:
Quote[/b] ]I'm just at the point where I want to  push myself a bit more when diving and start to do some planned deco dives.  At the moment I dive a single + pony with a BC.  So I need to spend a bit of money getting the right kit, wing, BP twins etc.
Most people try to minimise deco and the first way to do that is to dive Nitrox. This enables longer dives with no deco. A much better alternative than planned deco. For dives with a few minutes of deco you have perfectly adequate kit. If you start to chalk up the deco and want to reduce it then you're into accelerated deco - stages or CCR (SCR requires stage cylinders to switch gas just like CCR Edit that should say OC). To do this most people would suggest that you upgraded your kit.

Note that Nitox is a prerequisite for SCR or CCR training.

As for comparing costs then you will never recoup your money on a CCR if you dive to less than 50m within 10 ish years. Theres a thread on Dnet where Vic and I discuss this. Here

Scotty
 

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I went DIR... but my bungies pulled me back!
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Discussion Starter · #8 ·
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Thanks for all the help so far, lots to read on the other threads.

I am currently Adv Nitrox qualified and am used to using the extra bottom time.  I dont currently plan my dive with deco, but follow my computer and monitor my gas and will do up to about 5 min deco if I feel the site is worth the extra.  However more and more I want to stay longer.  I'm not too fussed about going deeper than about 40mtrs as I have a low narcosis threshold, by 40 mtrs I know I'm not safe and really have to concentrate.  

I'm just looking for the best way to extend my bottom time in the 30-40 mtr range.  Get twins and use a rich deco mix, or go for a rebreather, SCR or CCR.
 

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[b said:
Quote[/b] ]I'm just looking for the best way to extend my bottom time in the 30-40 mtr range.
Unless you have a huge breathing rate then twin 10's. Initially without a stage  though you may eventually find that limiting and move onto a 3 or 7L stage.

A CCR or SCR wont give you anything that the above supplies. Except higher capital outlay and more complexity before and during the dive.

Scotty
 

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In my (Humble) opinion you need to go through the twin thing before moving onto rebreathers.

In the end the biggest decider for me was when I physically could not get off the ground with out help when wearing my twins plus..........


I still dive with twins guys (one of whom regularly also dives ccr  (i'm scr)).  The main difference is weight out of water, proceedure in entering and setup discipline. Oh yes the VR3 was a little expensive to monitor my ppo2 (There are cheaper ways and some say it is not necessary on scr but I value my life)


Taking the dive computeer out of the equation rebreathers are still more expensive and for me on a scr depth is an issue.Having dive at Easter in the Farnes then refills are also an issue


Would I go back to Oc?  No

Why not?
weight, NOISE!, freedom.  

Will I move on to CCR?  Probably but by modifying my SCR.
 

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Charter Boat Skipper, Salvage Diver & YBOD abuser
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<font color='#000080'>OK SORRY!
I missed out the the fact it was based on a 21% table

I only posted to point Darren to the "costs involved" thread and threw in a rough example- couldn't be ar*ed doing any proper maths, just picked some approx figures from Bsac Nitrox
tables and Proplanner for Insp.
Yes you can do a similar dive on 40% if you don't mind humping twin-twelves around on a pootle dive and don't mind going to the edge of the MOD.

Do I detect some YBOD -envy from the direction of MSS?

Have fun,
               Terry
 

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do you think in 20 years from now oc will even be an option?

you dive deeper, longer and safer due to the advancement of your kit

rebreathers are coming into mainstream diving, it is just a mater of time befour we all take them for granted

then you can hang your twins up next to your wet sute and ablj

just make sure you pick an established rebreather with established courses,
 

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[b said:
Quote[/b] ]Yes you can do a similar dive on 40% if you don't mind humping twin-twelves around on a pootle dive
I don't use twin 12's on a 60m dive why would I use them on a 25m dive? As for weight my twin 10's weigh less than a RB plus weight belt - something else I don't need.

[b said:
Quote[/b] ] don't mind going to the edge of the MOD.
Sorry but your talking BS again.

[b said:
Quote[/b] ]do you think in 20 years from now oc will even be an option?
The navy have been using RB of various types for over 60 years they still haven't given up on OC. They still only use RB for specialist tasks such as mine clearing or sneaking up on an enemy coast line. As these are not things I plan on doing soon, I don't think I'll switch to a RB just yet. Though that's not to say that as technology improves the costs and safety issue may change. Though if you want to peer into a crystal ball the Japanese have tested an artificial gill that extracts Oxygen from sea water. So as long as you can guarantee a flow of 200l/min of water into it who needs an O2 bottle :)

[b said:
Quote[/b] ]rebreathers are coming into mainstream diving
Not at £4400 a pop they wont.

Scotty
 

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That's Dude with an E
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[b said:
Quote[/b] (Mark Scott-Simons @ April 29 2003,00:06)]
[b said:
Quote[/b] ] don't mind going to the edge of the MOD.
Sorry but your talking BS again.
There you go again Scotty acusing someone of talking BS,

on your last post you were talking about 40% at 25 mtrs which is the mod at 1.4pp

Terry admitted that he didn't state his example was based on 21% however almost everyone who read his post would have assumed that because he didn't sate a mix it was 21%

However you didn't state what mix your "I dive oc for 60 mins at 25 mtrs with no deco" was based on.

I'm not trying to cause an argument, but hey, this forum prides itself on informed discussion and not just acusing people of BS
 

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[b said:
Quote[/b] ]I'm not trying to cause an argument, but hey, this forum prides itself on informed discussion and not just acusing people of BS
When people discuss facts and opinions with me I'll discuss facts and opinions back. If people just state crap then I'll call it what it is. If they want to justify their BS then let 'em. I explained that in response to your earlier post in this thread.

But in answer to you statement re 40% at 25m. Now unless the definitions have changed 1.4 is the partial pressure at the TOD Whereas 1.6 bar is the partial pressure at the MOD. Or at least it was for most if not, all the agencies that I trained with.

[b said:
Quote[/b] ]Terry admitted that he didn't state his example was based on 21% however almost everyone who read his post would have assumed that because he didn't sate a mix it was 21%
The argument put forward is typical of the methods employed by RB divers to justify their toys. In this case what was being said was:

If I dive on air for [email protected] 25m = 20mins stops

If I dive on Nitrox then I only have to do 1 minute.

Said like that where's the argument for using a RB?

Another example of this misleading approach is used by AP in their press ads, which then also give a RB profile that violates their own oxygen exposure limits.

Scotty
 

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That's Dude with an E
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[b said:
Quote[/b] (Mark Scott-Simons @ April 29 2003,01:36)]1.6 bar is the partial pressure at the MOD. Or at least it was for most if not, all the agencies that I trained with.
Now I could be wrong here, but as I understand it most agencys base there mod on a 1.4pp for the working part of the dive and 1.6 on the stops?

Now come on admit it, you were equally missleading as Terry stating 60mins @25mtrs, with no deco without stating o2%

The saying goes something like......
It takes a big man to admit....................can't remember the rest its late.

If I'm wrong with my coments above I'll admit it openly.........
 

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[b said:
Quote[/b] ]Now I could be wrong here, but as I understand it most agencys base there mod on a 1.4pp for the working part of the dive and 1.6 on the stops?
Whilst I agree with your numbers I will disagree, slightly, with your terminology. The depth limit for the working phase is , or at least was when I was taught, reffered to as the Target Operating Depth, TOD. The 1.6 limit being more cast in stone was called the Maximum Operating Depth, MOD.

That's why I called him on that point. Though do people still teach the different terms?

[b said:
Quote[/b] ]Now come on admit it, you were equally missleading as Terry stating 60mins @25mtrs, with no deco without stating o2%
Yep, but as I stated earlier I was playing by his rules.

Scotty
 

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That's Dude with an E
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Ahhh.
Now I understand.
The rules are
If someone posts a slightly missleading post-
1.First criticise then reply with equally missleading post.
2.Justify it by claiming playng by someone elses rules.

I should have realised, having brought up three children.
 

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Twins weighing the same as MY rebreather?   no

boys and their toys?     er..   ..  possibly

Would I go back? No

do I know anyone who has gone back? no


Do I know inspiration who wish they had not spent 4000 when they see my buddies 600 home build ... yep


Does this help Darren 27?      Hope so



But I still say go through the twin before moving onto the rebreather.  At the very least he'll be able to make an informed decision of one against the other.


I wonder if Mark has tried both twin and rebreather... I think I can guess the answer.

However (Here comes the can of worms!)  Just like stating that the is only one way to "Do it right" or any other polarised view- truth is in the eye of the beholder. Ask an Arsenal fan about Man U or Man U about Arsenal. Conservative against Labour.  Ferrari against McLarren, Estee Lauder against Mary Quant.... All have advantages ad disadvantages.





Damn I think I'm on the wrong website.


       ................. Is this Yorkshire Philosphers?
 
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