3 Bottle dives

[Bismark]

IMO, if you think you are going to fumble the stage switch, practice some more until you don't think you are going to do this.......

As for the 130's versus smaller tanks and stages, we are really only talking one stage here and at worst, for these kind of dives this is maybe 4 lbs with 15/55. I would not trade the redundancy of having that gas on my back with two regs, and an isolation manifold, for having that gas in a stage with no redundancy. All for a 4 lb decrease in back gas and the ability to hand off the stage to someone else in the event of wing failure AND drysuit failure...etc.? Not an equal risk assessment trade off in my view,

If I don't have to carry the extra bottle, then I will leave it at home. I don't have the experience of some of you guys here but I have done enough of this by now to see how the additional bottles add a lot of complexity to the dive in terms of logistics, etc. Keep it simple, and don't needlessly complicate things based on some questionable risk assessment.

Just my 2 cents.

Just realized that this might actually be a DIR thing........

 

[KMD]

The people tend to flub the stage switch rationale for a 200' dive scares me a bit. I understand rjack's point that he only has 25 minutes on the bottom and doesn't want to waste time with the switch. But what lamont is discussing seems like a really bad argument for not using stages.

Not waisting time on a switch arguement is just about as bogus as one can get. Lets see:

switching off a stage requires two glances down.
1) get our your double ender & glance to make sure you clip it to the light. Clipping off and stowing light can be done by feel.
2) get long hose reg and switch to it from stage reg
3) one glance to make sure you have your hand on the correct stage valve.
4) turn off valve and stow stage reg.

Everything else can be done by feel so you can continue to look reef, buddies or whatever.

 

[rjack321]

Not waisting time on a switch arguement is just about as bogus as one can get. Lets see:

switching off a stage requires two glances down.
1) get our your double ender & glance to make sure you clip it to the light. Clipping off and stowing light can be done by feel.
2) get long hose reg and switch to it from stage reg
3) one glance to make sure you have your hand on the correct stage valve.
4) turn off valve and stow stage reg.

Everything else can be done by feel so you can continue to look reef, buddies or whatever.

Have you ever done a bottom stage switch on the trigger? What about with a reel in your hand? Both? I have tried and adding the scooter and/or a reel adds to the complexity exponentially. On the trigger, you end up going to your necklace reg temporarily, even the reel has to be locked or handed off (or both), and stowing one handed with drygloves on is slow (and at least for me) and unreliable (its easy to drop the used reg). Rtodd hinted at some of these hokey intermediate steps earlier.

While its all "simple" its not something you necessarily wanna add if you don't need to. Certainly not without at least weighing an alternative like bigger backgas or using an intermediate deco gas instead. Only doing switches on ascent when you have time aplenty, frees up resources on the bottom when you have little bottom time and lots of other stuff going on (i.e. video, scooter, line, etc)

 

[RTodd]

Switching stages on an easy swim is a completely different animal than switching stages when under power on a scooter and time and speed are important. It slows you down a bit when going from one stage to backgas. It really slows you done when going from one stage to another.

Rjack, one trick is to leave clips on all of your stage regs like we used to do (and I still do) rather than using the loop. This allows you to come off of the stage reg and just clip it to the top part of the stage rigging. Then, you deal with the loop of hose as best you can, either tucking or stuffing under the rigging handle until you are stopped long enough to fix. It isn't a best case scenario but is one of the less than ideal things I mentioned we used to do when doing a complete switch on the fly. This forces you to go to the backup, leave the stage over your shoulder, get it turned off, then do the clip trick. All this can be done on trigger. After this is done, you go to the primary which may take a quick off trigger pause. Does that make sense?

 

[johnkendall]

Have you ever done a bottom stage switch on the trigger? What about with a reel in your hand? Both? I have tried and adding the scooter and/or a reel adds to the complexity exponentially. On the trigger, you end up going to your necklace reg temporarily, even the reel has to be locked or handed off (or both), and stowing one handed with drygloves on is slow (and at least for me) and unreliable (its easy to drop the used reg). Rtodd hinted at some of these hokey intermediate steps earlier.

While its all "simple" its not something you necessarily wanna add if you don't need to. Certainly not without at least weighing an alternative like bigger backgas or using an intermediate deco gas instead. Only doing switches on ascent when you have time aplenty, frees up resources on the bottom when you have little bottom time and lots of other stuff going on (i.e. video, scooter, line, etc)

Don't switch while on the trigger. If something goes wrong you can't have your team watching and available to help. If you're scootering and need to switch, stop, do the switch smoothly, then get back on the trigger.

If you can't do the switches smoothly with drygloves, then practice more with the drygloves, but don't make your life hard and dangerous by trying to switch while still on the trigger.

HTH

John

 

[RTodd]

Don't switch while on the trigger. If something goes wrong you can't have your team watching and available to help. If you're scootering and need to switch, stop, do the switch smoothly, then get back on the trigger.

If you can't do the switches smoothly with drygloves, then practice more with the drygloves, but don't make your life hard and dangerous by trying to switch while still on the trigger.

HTH

John

I probably should have added the qualifier that I don't like swithcing on the go anymore as discussed above. My view is that you can prep for the switch under power but if you really get smooth at it you don't lose much by stopping. Switching to your backup on the trigger isn't really that dangerous. But, if you do have an issue and have to come off the trigger, you risk losing your teammates unless vis is really good or you trust them enough to really be watching you/ your lights. When we were doing this we would signal the switch was happening and bunch up. Lead diver is easy to watch and be ready to help, when the second and then third switch you have to really be watching their lights.

 

[rjack321]

Good ideas. I have never actually switched on the trigger on the bottom. Just for practice and sorta on ascent. I work on it mostly to get the one-ish handed stuff down better, sometimes its helpful to be able to momentarily hit the trigger to stay in one place. This is esp. useful ascending up an upline but before shooting an SMB. We like to shoot the bag from a known place close to the upline. Using two hands means we need to lock off and at least temporarily stow the scooter and that takes alot of time and resources away from the dive (esp. if done on the bottom). After the 70ft switch we got time aplenty to deal with all of these things.

 

[KMD]

on a dive of the profile you were mentioned a 120' bottle really isn't giving you that much.

Benefits:

it allows you to accelerate deco through that stop by maybe 5 minutes or so.

Costs:

It adds an extra switch on Deco. Which adds unneeded complication when trying to stay on an upline in current.
It forces you to carry it for the entire dive but is only usable towards the end.
Its not useful on the bottom where gas usage is the highest.

In your example you did mentioned diving on a wreck? Where would you rather do a stage stow? on a wreck where there is shelter from the current or on an upline?

Also if miss the wreck, you can always do minimum deco up, and grab another bottom stage and try again. If you did it all on backgas you might not have enough for that second attempt.

 

[rjack321]

Personally, I would rather dink around doing a stage switch and moving bottles on the ascent than on the bottom. As efficient as I like to try and be, there's little rush to get out of the water.

Either way I am trying to stay near/close to a line. I think its probably easier without having a reel and/or video going on at the time.
Check depth
trigger
select bottle
trigger
depoy reg
trigger
check bottle
etc
Although I admit to having very few dives with all this going on.

I have no idea what minimum deco is from 200+ft. For us, missing = going home for the day. Its actually kinda hard to miss since we grapple the wreck and then can go over the hook a few times to confirm its actually set where we think it is.

 

[KMD]

I have no idea what minimum deco is from 200+ft. For us, missing = going home for the day. Its actually kinda hard to miss since we grapple the wreck and then can go over the hook a few times to confirm its actually set where we think it is.

pretty much anything under 5 minutes bottom would call for minimum deco. I was recomended though that even with minimum deco to switch to 50% when possible.