Why no slates?

[rjack321]

No, it's not.

Based on the most recent T1 notes I saw (~2006) a linear ascent from 70-30 is now taught. I don't know if that linear approach is extended to deeper bottles since I have never seen the T2 notes.

 

[rjack321]

Probably because the dive times get ridiculous in Mexico before deco even matters. RD doesn't work for most cave diving because the times are so long. RD has a fairly narrow time band in which it works. So, it breaks down for most cave dives. I use a bizarro combo of tricks, past experience, etc. But, I generally start with a deco planner table. For longer dives that you don't know the deco in your head, pull the table out of wetnotes. If you will have a scooter with you, one trick is to tuck the tables under an innertube wrapped around the upper part of the scooter after you start deco so you can easily reference it. This is really only helpful for longer exposures. You can do the same thing with a stage but it isn't as convienently accesable. And for most deco even if you glance at your tables it usually isn't complicated enough to need to continue referencing it so you can but the tables back in the wetnotes.

For the orginal question - DIR answer is no wrist slates. Reasons have been given above.

We started getting real deco in Mayan Blue with a stage. Not much though. I suppose if we were diving padi 32% tables we wouldn't have had any. Ours are Navy -20% EAD for the 32%

 

[MonkSeal]

Based on the most recent T1 notes I saw (~2006) a linear ascent from 70-30 is now taught. I don't know if that linear approach is extended to deeper bottles since I have never seen the T2 notes.

Obviously, it depends on the instructor. I completed T1 in 2006 and S curve was taught. T2 as well (spring 2008 - quite recent). Few days ago I joined experience dive at the end of T1 - same was taught.

 

[RTodd]

We started getting real deco in Mayan Blue with a stage. Not much though. I suppose if we were diving padi 32% tables we wouldn't have had any. Ours are Navy -20% EAD for the 32%

Again, real or perceived need for deco. Double stage dive in Mayan blue. Maybe some deco. However, keep in mind that a large part of the exit is pretty shallow if you stay on the roof. If you are familiar with the cave, keeping track of average depths and what kind of "deco" you are accomplishing on the exit, etc. the actual deco there is inconsequential. Plus, in class they make you practice a few minutes on the O2 bottle for most dives. That is enough deco at almost all of those sites anyway. Not trying to argue with you, just explaining.

 

[rjack321]

Again, real or perceived need for deco. Double stage dive in Mayan blue. Maybe some deco. However, keep in mind that a large part of the exit is pretty shallow if you stay on the roof. If you are familiar with the cave, keeping track of average depths and what kind of "deco" you are accomplishing on the exit, etc. the actual deco there is inconsequential. Plus, in class they make you practice a few minutes on the O2 bottle for most dives. That is enough deco at almost all of those sites anyway. Not trying to argue with you, just explaining.

From somewhere in F tunnel, I think we had 10mins. Our plans were in our wetnotes but even with a reasonable crapload of "problems" exiting, I don't recall having to break out wetnotes (or need a wrist slate) to ensure we followed our rather basic schedule. Since we came up with the deco plan while bobbing in the cenote under extreme mosquito duress I'm pretty sure we could have come up with another one UW from first principles if need be. IIRC already we had a light failure, I lost backgas, KMD lost his stage, and I had a deco reg failure. And still didn't need the deco plan on a wrist slate to follow it.

 

[Elemental]

Danny seemed to think our deco plans were fine. And we used west coast Joe Talavera 100ft=20min setpoint tables with -20% EAD for the MDL parts and divided by 2 to get the O2 time.

There's no reason it shouldn't be - they're teaching it as one of the deco tools after all. We used it in my C2 class - not everyone had DP or was T1 - with the caveat that it works well for the tourist caves of N FL. Start adding multiple stages or go deeper and it begins breaking down.

I prefer shaving off a few minutes of RD if my laminated tables permit it and it feels right. How that somehow suddenly makes me less than fully trained is unclear.

My T1 was in a different era, I don't know what they teach now although I do know shaping the curve is out.

Not as of the class a buddy took in 2007.

 

[Elemental]

Redirecting the thread for a moment, I don't think slates are that practical for DIR cave divers, but a wetnote sheet secured under two bands on a scooter could be useful for taking brief notes during a dive.

 

[rjack321]

How that somehow suddenly makes me less than fully trained is unclear.

That was a poor choice of words (I was thinking T1) but I'm going to putz with it.

 

[rjack321]

Redirecting the thread for a moment, I don't think slates are that practical for DIR cave divers, but a wetnote sheet secured under two bands on a scooter could be useful for taking brief notes during a dive.

I can barely read my kayak compass mounted on my short gavin hull. I'm not sure a wetnote sheet would be big enough to read an arm's length away.

 

[Elemental]

I can barely read my kayak compass mounted on my short gavin hull. I'm not sure a wetnote sheet would be big enough to read an arm's length away.

I'm thinking for noting time/distance/gas of interesting areas on the way in for checking out on the way back. Should be quicker than rearranging the light and pulling out the wetnotes each time.