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Drmike · 13th February 2008, 13:43

Quote: (Originally Posted by Dave Sutton)

Uhh..... Mike, you know I love ya, and we usually are like peas and carrots in the way we look at technical things, but:

Different environments drive different requirements, and the prism of your (or my, or anyones) experience often causes us to loose sight of the fact that other places may be different. I know that I make the error of assuming that everyone is diving anchor-line descent, non-drift deco, in cold water with minimum vis, a strong current, and three finger mitts, so sometimes I am incredulous that people think they can do some 'action' in the water when for them, in their environment it is easy. So, I can see that for some people it's hard to believe that is might be simply IMPOSSIBLE to do what seems a simple task elsewhere.

YES, Switch blocks are generally not needed. No argument. I've been able to rig my system to work without them. I play with them and I gently caress them at the dive shows (cannot resist nicely made chrome plated brass hardware), but... I don't own one. Come to think of it, I don't know anyone else who does either.

BUT:

Back to "my" environment, I'm not so sure I could hold my breath reliably long enough to switch a QD while task saturated in a high workload bailout situation on an anchor line deco, in sea-surge conditions, in minimum visibility, in a strong current, in a thick drysuit, with three finger mitts. If I bobble one thing it can go bad very fast. Bottom line is that if I am holding onto the anchor line for my life with one hand, I have one other hand left to do the rest. Having been there and done that.... it can be a task saturation condition that causes one to wonder how it'll all turn out. My solution is neither a switch block OR a QD that needs to be changed, but rather an integrated system that requires neither. The process of thinking it out drove the result. Then again... my rig itself has valves for switching (Mark-15 onboard/offboard Whitey), so one mans 'rig control' might be another mans 'switch block' mounted on a harness, eh?

So:

Best advice to our new correspondant is what Mark Nix suggests: Read the old threads and then make a decision, and then come back and ask a reasoned question if doubts still exist. Yes, the answer will 'probably' be "You can do without", but he'll have come to that point by self realization, and not by receipt of a dogmatic short-answer.

Hope you're well, bet there's no damned ice-storm happening there today!

Dave

.

Hi Dave, I agree different invironments suit different methods but I think a degree of standardistation is also useful. But to clarify I too dive in many conditions including the one you describe. Ive spent many-many a happy dive hanging for dear life off a violently bouncing anchor chain in bad viz and horendous currents. Not a fun place to be. Ive had my arm ripped out the socket, Ive been hit by the chain, by the boat, even had the chain hit my scooter and pop the end off it! - all very unpleasant I agree.

Hanging on with one hand I soon found was largely impossible given the typical currents and anchor chain bounce so I long ago stopped trying.

Basically the technique I developed would be I would attach a jon line to the anchor chain when still deep and below the depth where anchor chain would be bouncing uncontrolably. It would be an extra long and strong jon line. I attach it deep (when no bounce) but only start using it shallow when the bounce or current gets crazy. It has a Y end with a clip on each end of the y that clips to my 2 chest D rings. With the jon line both hands are free to do whatever needs to be done, Im safer as the anchor chain cant get ripped out my hands suddenly, and my hands are free.

My jon line would have an 'emergency release' clip about half way along - to release Id sometimes (but rarely) in really bad conditions unclip it there and remove the rest (thats stilll attached to anchor line) when we pull up the anchor.

I found when we reallly Must deco off the anchor/down line in raging currents that this method makes deco much safer and far less stressfull, it also negates the need for a switchblock

Of course drifting platform deco is preffered but not always possible

13th February 2008, 13:43	#15 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,157	Re: Switching blocks Quote: (Originally Posted by Dave Sutton) Uhh..... Mike, you know I love ya, and we usually are like peas and carrots in the way we look at technical things, but: Different environments drive different requirements, and the prism of your (or my, or anyones) experience often causes us to loose sight of the fact that other places may be different. I know that I make the error of assuming that everyone is diving anchor-line descent, non-drift deco, in cold water with minimum vis, a strong current, and three finger mitts, so sometimes I am incredulous that people think they can do some 'action' in the water when for them, in their environment it is easy. So, I can see that for some people it's hard to believe that is might be simply IMPOSSIBLE to do what seems a simple task elsewhere. YES, Switch blocks are generally not needed. No argument. I've been able to rig my system to work without them. I play with them and I gently caress them at the dive shows (cannot resist nicely made chrome plated brass hardware), but... I don't own one. Come to think of it, I don't know anyone else who does either. BUT: Back to "my" environment, I'm not so sure I could hold my breath reliably long enough to switch a QD while task saturated in a high workload bailout situation on an anchor line deco, in sea-surge conditions, in minimum visibility, in a strong current, in a thick drysuit, with three finger mitts. If I bobble one thing it can go bad very fast. Bottom line is that if I am holding onto the anchor line for my life with one hand, I have one other hand left to do the rest. Having been there and done that.... it can be a task saturation condition that causes one to wonder how it'll all turn out. My solution is neither a switch block OR a QD that needs to be changed, but rather an integrated system that requires neither. The process of thinking it out drove the result. Then again... my rig itself has valves for switching (Mark-15 onboard/offboard Whitey), so one mans 'rig control' might be another mans 'switch block' mounted on a harness, eh? So: Best advice to our new correspondant is what Mark Nix suggests: Read the old threads and then make a decision, and then come back and ask a reasoned question if doubts still exist. Yes, the answer will 'probably' be "You can do without", but he'll have come to that point by self realization, and not by receipt of a dogmatic short-answer. Hope you're well, bet there's no damned ice-storm happening there today! Dave . Hi Dave, I agree different invironments suit different methods but I think a degree of standardistation is also useful. But to clarify I too dive in many conditions including the one you describe. Ive spent many-many a happy dive hanging for dear life off a violently bouncing anchor chain in bad viz and horendous currents. Not a fun place to be. Ive had my arm ripped out the socket, Ive been hit by the chain, by the boat, even had the chain hit my scooter and pop the end off it! - all very unpleasant I agree. Hanging on with one hand I soon found was largely impossible given the typical currents and anchor chain bounce so I long ago stopped trying. Basically the technique I developed would be I would attach a jon line to the anchor chain when still deep and below the depth where anchor chain would be bouncing uncontrolably. It would be an extra long and strong jon line. I attach it deep (when no bounce) but only start using it shallow when the bounce or current gets crazy. It has a Y end with a clip on each end of the y that clips to my 2 chest D rings. With the jon line both hands are free to do whatever needs to be done, Im safer as the anchor chain cant get ripped out my hands suddenly, and my hands are free. My jon line would have an 'emergency release' clip about half way along - to release Id sometimes (but rarely) in really bad conditions unclip it there and remove the rest (thats stilll attached to anchor line) when we pull up the anchor. I found when we reallly Must deco off the anchor/down line in raging currents that this method makes deco much safer and far less stressfull, it also negates the need for a switchblock Of course drifting platform deco is preffered but not always possible __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment Last edited by Drmike : 13th February 2008 at 13:49.
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