I want to murder my computer and feed it to the fishies!

[Jax]

While I appreciate your input (Ian, Jim, drbill), I hope you understand that this thread is to discuss my computer - not my diving habits. Now I could go through though the posts and defend myself about the assumptions you are making (not planning, ascent rate, tank sizes, redundancy, discipline etc etc), but again that is not the point. I have a great instructor, a solid buddy, and I am going to learn whether you feel I am prepared to be making these dives or not.

So if anyone has any experience with the Mares M1 RGBM computer that is helpful - I would love your input. Specifically - is there a way of knowing when deep stops are coming up, why it doesn't count down deco reliably, and any other knowledge you can pass on.

Thanks guys

Melanie, the questions came up about your training because if you HAD training, you would know that ascending too slowly causes you to on-gas more than you off-gas. It is not the computer's "fault"; it is doing what it is designed to do.

It "sounds like" the way you are doing things will get you bent or you will run out of gas. The fellows are just expressing a warranted and genuine concern.

 

[DuboisP]

Hi - One obvious explanation of increase in deco obligation from 21 to 27 minutes during your ascent is that may have been a little slower than the computer was calculating for. If the computer is "expecting" you to ascend at 33 ft/min but you ascend at a slower rate, then you will be on gassing at a faster rate than initially predicted by the computer. This would be particularly noticeable at depths greater than 30 ft on a dive profile such as you have described, and it will add additional time to your stops

i agree.
with the Mares M1 RGBM, you must be around 10ft to have a good deco, else the minutes are very long
according the user guide, the ascent rate is based on 10m/min (33ft/min)

Melanie, are the altitude setting was correct ? the M1 RGBM doesn't have settings to hard the algorithm, but you can use the altitude setting to mimic it.

 

[DuboisP]

What's the serial number? Maybe you have one from the recall?

The recall affects Mares M1 dive computers with the following serial numbers.

Mares M1

Serial Numbers between 22783 and 22902.

Serial Numbers between 23019 and 23045.

was for the M1, not for the M1 RGBM

 

[DuboisP]

<<Recreational divers should NOT dive deeper
than 40m (130 ft). Although this computer
will continue to provide information for
compressed-air dives deeper than 40m
(130 ft.), the risk of nitrogen narcosis and
decompression sickness (DCS) is greatly
increased; therefore this information
should be treated as only approximate. >>

completed :
MARES recommends that divers never exceed the
maximum permitted depth for their qualification.
Diving below 130 feet (40 meters) or outside the nodecompression
limits significantly increases the risk
of decompression sickness.
NEVER dive deeper than 130 feet (40 m) or
do planned decompression dives with the
COMPUTER unless you are a trained and
certified technical diver (IANTD, TDI, ANDI,
PSA, etc.) familiar with the skills and risks of
deep air diving, and licensed at least to the
level of Deep Air diving for depths beyond
130 feet (40 m). Even with this level of
certification and experience, this type of
technical dive entails a much higher risk of
DCS, regardless of the dive table or
computer used. You must be aware of and
willing to accept these risks before
attempting such a dive.

Always ascend several minutes before going into DEC
mode, and allow yourself even more time in the case of
cold water conditions, repetitive dives deeper than 60
feet (18 m), or for any dive involving unusually high
exertion. Failure to do this will increase your risk of
decompression sickness.

i have some dives at > 130ft with my Mares M1 RGBM (my 1rst computer, always used sometimes), 20 min bottom, 45 min out

 

[melanie.]

Jax - I understand the concern, really I do. And I do appreciate it. But the thing is I am tired of people just saying well you don't know what you are doing so you are going to kill yourself. How about some constructive criticism please? Telling me just not to do it is not going to change anything. Help me learn instead

Like I came on here asking for help with my computer - then I get told because I don't know my computer I shouldn't be using it? Come on already. I have done all the reading I possibly can think of on the thing and am beyond theory learning. I am currently trying to figure out how it works in real life situation.

And the ascent rate, ok yes I know. But what I am not understanding is that my buddy right next to me - who is going up the same speed of me - is not getting any extra deco on his computer? When he starts going up it stops adding deco, heck it even takes some off. So is my comp just being it's uber-conservative self or am I doing something wrong? Should I be attempting to speed up my ascent or should I just take into consideration before hand that it will continue to add on and keep my slow and steady pace. Because it is stuff like this that I can't know before hand, that I can only learn about by doing.

=C= - thanks for the link, but my computer was not affected by the recall. (It is the RGBM model)

inventor - oh don't worry I can't wait for the day I get to upgrade If only the world didn't revolve around money

 

[ianr33]

I have a couple of rules of thumb when it come to dive computers:
Any computer that tells you to ascend before going into deco is not designed for deco diving.
Any computer that has a 3 minute safety stop countdown after clearing deco stops is not designed for deco diving.

 

[melanie.]

i agree.
with the Mares M1 RGBM, you must be around 10ft to have a good deco, else the minutes are very long
according the user guide, the ascent rate is based on 10m/min (33ft/min)

Melanie, are the altitude setting was correct ? the M1 RGBM doesn't have settings to hard the algorithm, but you can use the altitude setting to mimic it.

That's what I don't get, I was at EXACTLY 10 feet, no reason for the minutes to take so long.
The altitude is set to P0 (0-2300ft). The least conservative setting possible

 

[ianr33]

Jax - I understand the concern, really I do. And I do appreciate it. But the thing is I am tired of people just saying well you don't know what you are doing so you are going to kill yourself. How about some constructive criticism please? Telling me just not to do it is not going to change anything. Help me learn instead

You don't know what you are doing. You may or may not kill yourself.

The internet is not the place to learn deco diving.

Get trained. Please.

(All meant constructively)

 

[DuboisP]

Any computer that has a 3 minute safety stop countdown after clearing deco stops is not designed for deco diving.

these 3 minutes are optional. RTFM

Get trained. Please.

there are other ways to get trained than to go to school.

Cousteau didn't have a C-card.
We are here people with a 1rst level c-card, but are expert on CCR, without C-card.

 

[ianr33]

these 3 minutes are optional. RTFM

Not optional, dumb!

So I've just done an hours deco,the last 30 minutes on 100% O2 and the computer wants an "optional" safety stop??!!

My Predator does not have a safety stop countdown and I'm guessing the X1 doesn't either. My point was that any computer with a safety stop countdown is really a recreational computer no matter what the sales literature may say.