Uprights vs inverts vs slob knobs etc

[Digger]

So, the age old debate returns. This is something I’ve been thinking about a fair bit, and I thought I’d jot some ideas down to try and help others who might not have walked this path yet.

You’ve bought your first twinset, so you have a major decision facing you. Which way up.

You will see a massive number of different configurations with hoses, regs, different wings, backplates, BCDs, you name it. I will try and avoid discussing all of these where I can, and focus on the issue in hand.

Upright cylinders first.

Tanks are this way up for a number of reasons. Sometimes quoted is the old twin hose regulators we used to use which required the tank valve to be behind the head. For me this is only part of the reason. The major advantage to having your tanks upright is they stand up easily. A set of twins will sit much more happily with the bottom of the tanks on the deck than on any stand I have seen in production. They are more stable.

The other major plus to doing things this way is the use of standard hoses (normal hoses you will either already have or can easily be bought off the shelf for not a lot). It allows a simple hose routing from the 1st stage behind your head around to the mouth There are a number of guides to doing this, and following the DIR instructions gives you a good place to start.

One thing I am hot on is trying to get things relatively standardised where you can. You make life easier for a rescuer/buddy if your kit is configured in a way which is as close to their expectations as possible. Take for example which reg comes off which post. If I see a diver with a freeflowing reg in their mouth I will come to their assistance where I can. If they are struggling reaching back I will automatically go for the right post (for the diver wearing the set – assume all left and right post references are looking at the back of the twins), and at the same time if the backup is the problem I will automatically go for the left. In the event of running things the other way around this could cause a bit of a problem if I turn off your backup as you switch to it, and you want the problem reg to be closed as fast as possible to save as much gas as possible.

Having your tanks the right way up makes it easier to see which hose does what. I can look at your gear on the bench before we dive and I already know what inflates what, which reg is which, because I can see where the hoses run. This is a good habit to get into before a dive – look at your buddy’s kit. It might just save their life. Get them to look at yours too, it might just save yours. A buddy check should cover all this but this is just a belt and braces – I have been there more than once when someone tells me something in a buddy check which I know isn’t true and they’ve realised their mistake when I point it out. No biggie, it helps both of us and prevents problems in an emergency. It’s normally when someone’s been reconfiguring things they make this mistake, or when borrowing someone else’s set. This is something DIR has nailed – the gear is the same, so no problem there, you can just check it and your buddy checks etc and responses are the same. Great. We should all take a lesson from this.

In the grand list of advantages and disadvantages I am careful about putting valve access in the advantages. The reason for this is because it is an advantage for me – it is easier for me to reach my valves upright than inverted. I know this is different for others, but it shouldn’t be. There are those that physically find this more difficult (Mark Chase’s various attempts to solve his shutdown problem using uprights is well documented on here and elsewhere, he is barrel chested. There is not a lot he can do about this, and for him it will always be easier to reach a valve next to his arse than a valve behind his head. Nigel Hewitt has old motorbike injuries which make the situation the same. I am a young fit thing with only one shoulder injury to my name, which hasn’t affected my mobility in this area, so easy for me, but my sympathy to those who don’t find it so easy). There are also those who do not have the fit of their suits etc right. I see this a lot when talking to divers about shutdowns. They tell me they cannot reach their valves. I can get them to reach their valves in a t-shirt or jumper, so they should be able to get there in their suit. Obviously there is a certain amount of bulk in a drysuit and undersuit, but this should not be excessive. I can get there in a 400gm undersuit with 2 layers of thermals on in the depths of winter, so people who complain a 200gm undersuit is stopping them shutting down just doesn’t cut it. It’s either the fit of the suits or they can’t reach them at all out of their suit.

All this said I believe quite firmly that 90% of all divers should have no problems shutting down and reaching any of their valves. If you’re in the 10% then that’s life, but get someone who knows what they’re doing (as in a decent tech instructor or experienced diver on twins) to analyse what you’re doing. It’s not rocket science, but you may well find there’s things you’re doing you don’t even realise, or there’s equipment you’re using which is making life difficult for you. Sometimes a fresh pair of eyes can help you see the woods from the trees. I know Mark Powell runs coaching days where there is no set agenda, you could talk to him about the problems you are having and he could well be able to do this, as would instructors from a number of agencies who are active on the board. I’ve offered before and I am happy to go diving with people and try and help them if they want it, but not in a formal training course setup. All I have is a bit of experience seeing a lot of divers taking their first steps in twins and wings etc and have seen many of the common mistakes time and again.

I understand cost is a factor. A good drysuit will cost you £500 minimum, and there’s plenty of bad ones out there for the same money. If you can’t shut down in your suit it won’t kill you to invert or use a slob knob for a year while you save up. Neither will it kill you to do it this way forever. For me I got a new suit and suddenly found I didn’t need to invert, but it took 6 months of diving the suit to realise that reaching that way wasn’t an issue any more. It just didn’t cross my mind until a friend asked me why I was inverting my tanks, and I realised the problem wasn’t there any more.

The only pieces of advice I think people need to shut down are these:

• Get the bands right. Set them as high as the top band will go on the tank, so the top of the band is at the ridge before the tank curves toward the neck. This is the right place to have it, and your trim should be ok with it there. Don’t think that higher tanks will make shutdowns easier, it won’t.

• Get the harness right. A badly fitting harness is about as good as a wet bit of toilet paper. Follow the fitting guides, this again is something the DIR websites have well documented and they’re about right. Personally I have a few modifications to my harness, but the fit is the same. Snug but not too tight. Make sure the D-rings at the shoulder don’t interfere with your arm movements.

• Practice. When working out how to do it, and making changes to your rig, do 6 dives before you do anything else. This gives you time to work out whether it really is better or worse, instead of giving up on an idea because it didn’t work on one dive where another factor could be an issue. Above all keep working on getting to the valves, making sure you know which way they turn to on and off, and get good at shutting down. There are no tech courses I have done where shutdowns weren’t a major part of the drills. You need to be able to shut down at a moments notice, get it right first time, and not kill yourself in the process. My experiences at Nitrox, Deco Proc and Trimix courses was that being able to shut down with ease made the whole course 100 times easier. I watched others struggle with shutting down and it made the whole course much more stressful and difficult, and in some cases complete overhauls of what they were doing became necessary because they hadn’t worked on their shutdowns and nailed it. You will know when you have it sorted, it just feels right. You will also know when you haven’t. Once you think you’ve got it, take your mask off in some really cold water, then do it. It will take your mind off the skill and see if you still do it the same way and in the same time. You should. Once that’s sorted lay yourself 50 metres of line, take your mask off and swim down the line shutting down. When you get to the end put your mask back on and check all your valves. Then do it again. If you can do these without problem then you will have dealt with the worst case scenario you are likely to encounter on a dive. Andy Hayhurst used to use this skill on courses, and it’s one I regularly use to make sure my head and skills are still in the right place for the diving I am doing. It’s a good one, and it works. Obviously make sure if you’re doing it for the first time you do it somewhere shallow and with an attentive buddy. You don’t want to drown practicing a skill you read on the internet, that would be foolish.

• Get everything out of the way of the knobs. If you can reach then that’s one thing, if you then have a whole load of gear in the way of turning the things you might as well not be able to reach. A good clean configuration is what you’re after.

So, we’ve covered that base fairly comprehensively I think. If you can, dive your tanks upright. It makes a lot of sense for a lot of reasons. But if you can’t, you’re not going to explode or die in a horrible accident, you just need to find a different way to shut down.

Other ways to shut down:

Invert your tanks.
You can invert just about any twinset. It works well with 10s because they’re shorter and don’t tend to make you head heavy as 12s can with the bottom of the tanks high up behind your head. I found to trim out a set of 12s I had to run them quite low on my back which made the gains in being able to easily reach the valves weren’t quite as good as they should have been.

Trouble is with inverting tanks is you need to spend a lot of money doing it. Start off with a valve guard. Forget CD guards, simply not strong enough, and not designed for the job. What you need is something like the Ritherdon guards, or something like the ones Steve has had made up. They cost money, but they are what you need. Then you need one for each of your twinsets (unless you want to undo the bolts every time you change sets) and I would carry a spare one in case you need to use someone else’s twins. Another problem I had diving inverts – borrowing twinsets. The valve guard I had simply didn’t fit a set I was lent, so we ended up in all sorts of fun trying to get that on before a dive.

Next cost is custom hoses. Anyone who reckons they can do it with standard hoses is plain wrong. You need a long hose to run from the valve to your inflator. This needs to be around 1 metre long. Then you need to start thinking about how to route all your other hoses. I have seen various configurations but one of the neater ones included a 1.5m primary routed from the right hand side hoglooped, and a 1 metre long secondary routed up the left hand side of the backplate and round the right hand ride to a necklace under the chin. Trouble is now you have 3.5m of low pressure hoses kicking around (without the required drysuit inflator), and the more hose you have the more chance of a problem if you ask me. A traditional upright setup has just under 3m of hose by my reckoning, so a bit of a saving. Plus the cost of hoses. My long hoses were made up specially and weren’t cheap (£30+) whereas the hoses for the upright setup are all there in the shop ready for you, and cheaper.

Now here is the real reason the inverts got binned a few years ago. Stages and other guff. We all carry around reels, SMBs, crowbars, air chisels, you name it. They get in the way. You reach back to get to your isolator and have to move a load of gear out of the way to get to them. Not what you want. You want clear unimpeded access. Now stages. I have seen all sorts of comedy arguments about inverts and stages, largely centred around “you can push them out of the way” which is lovely and everything, but there comes a point when you can’t. A couple of decent sized stages and you won’t get there easily. Try clipping a couple of AL80s on one side and reaching your arse. Doable maybe, but I don’t want shutdowns to be doable, I want them to be textbook. Now, if you don’t plan on doing more than twinset diving for a while, don’t carry a lot of gear on your sides, and don’t mind the cost of the hoses and stands then go ahead. Honestly, it’s a fine way to dive. It does a job, and there’s plenty of firemen and navy divers who will agree with you all the way. Personally it’s not for me any more, because I have no problems reaching the valves upright, so all the arguments for inverting the tanks become kind of neutralised. The only good argument for me (and it’s not a very good argument) to use inverts is protecting the first stages. I have been in holes in wrecks where I have battered my way through with the twins, where if I was using an upright setup I’d have had to do things a bit more carefully. Gear takes a bash or two on top quite regularly, and no decent first stage should ever be damaged by the impact a diver can create. You just don’t make enough force to break anything. Hoses on the other hand you could damage, along with knobs on the set, but in reality it’s fairly unlikely.

OK, so you can reach the right and left hand posts, but can’t get to the isolator. Get a slob knob?

No.

Now this might cop a bit of flack, but a slob knob is a crap solution to the problem. Upright or invert. Those are the options. The isolator is the single most important thing you absolutely have to be able to get to and deal with. And you want to attatch a big fitting with a piece of wire down the middle to a knob? Empirically I’ve never seen one fail. I’ve also not heard a lot of stories of them failing. But it would only have to be the once and you could get yourself in some deep doo-doo.

The other argument on this one is if you can reach the right and left comfortably what’s stopping you getting to the middle one? If you can only just get fingertips to the right and left ones then you need to either make the changes at the start, or invert the tanks. It’s not good enough to just about be able to shut down, it needs to be easy. Otherwise you might as well dive one big single tank, which is very nice but not all that safe on deeper dives.

If you do choose to get a slob knob to sort your problem (which I’m not advising, but some people don’t take my advice, as from time to time it has been known to be a little out) then make sure it works perfectly every time. Check it isolates on the dive, check it on the surface, get your buddy to check it, make certain. In the same way on the way down the shot I check my valves, slob knob users should do the same. If it fails your dive is over. Get on and up before anything else has the chance to go wrong.

Other options include diving independent twins. They’re fine for most diving, they do require an extra gauge, and they do require careful management if someone comes at you out of gas. But they’re a whole lot safer if you can’t reach the knobs. Diving a manifolded set with the isolator shut is just horse shit. Sorry but it is. You get all the disadvantages of independents with none of the advantages. If you’re going to dive like that get yourself down to the LDS and buy a couple of blanking plugs for the valves.

So the advice is fairly simple from me:

Dive uprights. Practice your pants off. Make life hard for yourself. Get your buddies to make life hard for you. Check everything twice. Make sure you can shut down and make sure it feels right. Watch some decent tech DVDs on how to shut down. If it feels like that then you’re ok. If it doesn’t keep practicing. Leigh (yippeediver) has spent a whole lot of time practicing with a new stage, and with twins, and a whole lot of other gear. We might take the piss out of him diving Stoney a lot, but when you first get your twins you need to do it. Drills on top of drills on top of drills. When everything’s textbook then you can go and play in deep water knowing you can rely on your skills and your gear. You don’t have to do it in Stoney, go do some 20m wreck diving if you want, but make sure you keep on at the skills. And don’t be lulled into having a whole load of gas on your back, not until you can shut down with ease.

If you can’t reach the valves invert your set. It makes sense, but understand the drawbacks. In some cases it is using equipment to solve a technique problem, in others it’s using equipment to get around what is effectively a disability (in a diving sense, you can’t reach where you need to, so you are at a disadvantage to those that can) but remember the 90% to 10%. Just make sure you absolutely are in the 10% before you spend all that money and reconfigure your gear.

Finally if you can’t reach your valves, don’t want to invert, get independents. Again, you’ll have some practice to do, but at least you won’t spend all year doing shutdown drills, and can happily watch a freeflowing reg piss gas everywhere and come up on the other one. Cock up your gas management using indies and it will kill you, so don’t get complacent with that. Simple.

Anyway, enough of my ranting. I just wanted to jot a lot of this down because I thought it might help. Some of it seems fairly “my way or the highway” which it isn’t – you can dive any way you like, but some of the stuff above might save you a few years and a lot of money pissing about with your gear. It might also stop you looking a prat at some point, and having to buy me a gallon of beer for saving your life. Plus there would be several years of pisstaking. Honestly, really bad pisstaking that you wouldn’t like much.

Digs.

[Angus]

Nice long post - Welcome back Bren!

[Jen S]

Originally Posted by Digger

There are also those who do not have the fit of their suits etc right. I see this a lot when talking to divers about shutdowns. They tell me they cannot reach their valves. I can get them to reach their valves in a t-shirt or jumper, so they should be able to get there in their suit. Obviously there is a certain amount of bulk in a drysuit and undersuit, but this should not be excessive. I can get there in a 400gm undersuit with 2 layers of thermals on in the depths of winter, so people who complain a 200gm undersuit is stopping them shutting down just doesn’t cut it. It’s either the fit of the suits or they can’t reach them at all out of their suit.

Yep, hate to admit it but he's right here. I've never not been able to reach my valves, but was VERY suprised how much easier it became when I changed my from a bulky 200g undersuit to a set of Xerotherms. The cut of my suit still isn't ideal, but I'm planning on getting a new one soon as fancy an upgrade (just got to decide Outer Edge or O Three!)

Originally Posted by Digger

I am a young fit thing

mmmm, no comment

Jen

[DIVE BUDDHA]

yes diggs ive seen many people with inverted twins!!!

but ive never had problems reaching my knobs and although ive put on a slob

knob that is bungeed to the underside of my backplate although i dont use it on a

shut down unless i know that ive got mannifold problems

i spend lots of time during dives whilst others are swimming along nailing my shut

downs ! even taking on

board peoples views on the way i do stuff !! and maybe how i can improve the

way i dive as im always learning and can take stuff on board to see if it makes my

life easier if it dont it gets thrown away ! me and mark and jim and alex doing

drills in the freezin cold on the shelf at stoney !

[ardhill]

Oi who hacked into Diggers account?

Some DIR person I reckon.

[Steve S]

Originally Posted by Digger

Upright cylinders first.

Tanks are this way up for a number of reasons. Sometimes quoted is the old twin hose regulators we used to use which required the tank valve to be behind the head. For me this is only part of the reason. The major advantage to having your tanks upright is they stand up easily. A set of twins will sit much more happily with the bottom of the tanks on the deck than on any stand I have seen in production. They are more stable.

Have a good look at mine the next time I see you, you'll find they are as stable as a booted set and a damn site more stable than a bootless set

Originally Posted by Digger

The other major plus to doing things this way is the use of standard hoses (normal hoses you will either already have or can easily be bought off the shelf for not a lot). It allows a simple hose routing from the 1st stage behind your head around to the mouth There are a number of guides to doing this, and following the DIR instructions gives you a good place to start.

I use a standard hp 1.5m and 2m hose

Originally Posted by Digger

One thing I am hot on is trying to get things relatively standardised where you can. You make life easier for a rescuer/buddy if your kit is configured in a way which is as close to their expectations as possible.

Yes I remember seeing a picture of 2 dyson rebreather guys in Stoney

Originally Posted by Digger

Take for example which reg comes off which post. If I see a diver with a freeflowing reg in their mouth I will come to their assistance where I can. If they are struggling reaching back I will automatically go for the right post (for the diver wearing the set – assume all left and right post references are looking at the back of the twins), and at the same time if the backup is the problem I will automatically go for the left. In the event of running things the other way around this could cause a bit of a problem if I turn off your backup as you switch to it, and you want the problem reg to be closed as fast as possible to save as much gas as possible.

Can't speak for other inverters but my left post hoses goes up the side of my wing and over, and the right reg is hog looped and that is yellow so little chance of confusion there unless you are part of the 10% of mentally challenged members of the diving fraternity

Originally Posted by Digger

Having your tanks the right way up makes it easier to see which hose does what. I can look at your gear on the bench before we dive and I already know what inflates what, which reg is which, because I can see where the hoses run.

See above

Originally Posted by Digger

This is a good habit to get into before a dive – look at your buddy’s kit. It might just save their life. Get them to look at yours too, it might just save yours. A buddy check should cover all this but this is just a belt and braces

Agreed, but fail to see why inverts would affect this in a negative fashion

Originally Posted by Digger

DIR has nailed – the gear is the same, so no problem there, you can just check it and your buddy checks etc and responses are the same. Great. We should all take a lesson from this.

Vive Le difference also are you suggesting we all go DIR or just Do It Digger

Originally Posted by Digger

In the grand list of advantages and disadvantages I am careful about putting valve access in the advantages. The reason for this is because it is an advantage for me – it is easier for me to reach my valves upright than inverted. I know this is different for others, but it shouldn’t be. There are those that physically find this more difficult (Mark Chase’s various attempts to solve his shutdown problem using uprights is well documented on here and elsewhere, he is barrel chested. There is not a lot he can do about this, and for him it will always be easier to reach a valve next to his arse than a valve behind his head. Nigel Hewitt has old motorbike injuries which make the situation the same. I am a young fit thing with only one shoulder injury to my name, which hasn’t affected my mobility in this area, so easy for me, but my sympathy to those who don’t find it so easy). There are also those who do not have the fit of their suits etc right. I see this a lot when talking to divers about shutdowns. They tell me they cannot reach their valves. I can get them to reach their valves in a t-shirt or jumper, so they should be able to get there in their suit. Obviously there is a certain amount of bulk in a drysuit and undersuit, but this should not be excessive. I can get there in a 400gm undersuit with 2 layers of thermals on in the depths of winter, so people who complain a 200gm undersuit is stopping them shutting down just doesn’t cut it. It’s either the fit of the suits or they can’t reach them at all out of their suit.

Valve access on twins is everything you can't reach your valves then you are diving a large single, as I said earlier I get so pi**ed off that people assume inverting is only for the infirm. I have more respect for a diver who will work around a problem by changing configuration than a diver who can't shutdown and dives uprights just to fit in.

You and others mention the exorbitant cost of hoses and stands but what is that compared to a new suit?

Originally Posted by Digger

All this said I believe quite firmly that 90% of all divers should have no problems shutting down and reaching any of their valves. If you’re in the 10% then that’s life, but get someone who knows what they’re doing (as in a decent tech instructor or experienced diver on twins) to analyse what you’re doing. It’s not rocket science, but you may well find there’s things you’re doing you don’t even realise, or there’s equipment you’re using which is making life difficult for you. Sometimes a fresh pair of eyes can help you see the woods from the trees. I know Mark Powell runs coaching days where there is no set agenda, you could talk to him about the problems you are having and he could well be able to do this, as would instructors from a number of agencies who are active on the board. I’ve offered before and I am happy to go diving with people and try and help them if they want it, but not in a formal training course setup. All I have is a bit of experience seeing a lot of divers taking their first steps in twins and wings etc and have seen many of the common mistakes time and again.

I'd love to know where you get your 90% from mate? other than that I agree although I seem to remember reading reports on here that it doesn't help everyone achieve upright shutdowns.

Originally Posted by Digger

Trouble is with inverting tanks is you need to spend a lot of money doing it. Start off with a valve guard. Forget CD guards, simply not strong enough, and not designed for the job. What you need is something like the Ritherdon guards, or something like the ones Steve has had made up. They cost money, but they are what you need. Then you need one for each of your twinsets (unless you want to undo the bolts every time you change sets) and I would carry a spare one in case you need to use someone else’s twins. Another problem I had diving inverts – borrowing twinsets. The valve guard I had simply didn’t fit a set I was lent, so we ended up in all sorts of fun trying to get that on before a dive.
Next cost is custom hoses. Anyone who reckons they can do it with standard hoses is plain wrong

I disagree about lots of money needed and my stand cost £55, also I dived for 6 months with a standard long inflator hose with no problem as the OMS when facing forward has a long corrugated hose which I routed under my arm.
I've not tried lending twins yet so can't comment about that but I still have my CD stand and that seems pretty interchangeable.

Originally Posted by Digger

My long hoses were made up specially and weren’t cheap (£30+) whereas the hoses for the upright setup are all there in the shop ready for you, and cheaper.

misleading mate, other than a custom lp hose all the others are standard

Originally Posted by Digger

Now here is the real reason the inverts got binned a few years ago. Stages and other guff. We all carry around reels, SMBs, crowbars, air chisels, you name it. They get in the way. You reach back to get to your isolator and have to move a load of gear out of the way to get to them. Not what you want. You want clear unimpeded access. Now stages. I have seen all sorts of comedy arguments about inverts and stages, largely centred around “you can push them out of the way” which is lovely and everything, but there comes a point when you can’t. A couple of decent sized stages and you won’t get there easily. Try clipping a couple of AL80s on one side and reaching your arse.

I take your point with the Xmas tree effect, but with a little thought I've encountered no gear stowage problems with 2 stages, 7's though as I don't dive an 80.

Also with them being steel combined with an extended bottom clip it is easy to slide my arm down the inside

Originally Posted by Digger

The only good argument for me (and it’s not a very good argument) to use inverts is protecting the first stages. I have been in holes in wrecks where I have battered my way through with the twins, where if I was using an upright setup I’d have had to do things a bit more carefully. Gear takes a bash or two on top quite regularly, and no decent first stage should ever be damaged by the impact a diver can create. You just don’t make enough force to break anything. Hoses on the other hand you could damage, along with knobs on the set, but in reality it’s fairly unlikely.

yes and if you leave the boots on you won't even scratch the bottom of your cylinders

Originally Posted by Digger

OK, so you can reach the right and left hand posts, but can’t get to the isolator. Get a slob knob?

No.

Now this might cop a bit of flack, but a slob knob is a crap solution to the problem. Upright or invert. Those are the options. The isolator is the single most important thing you absolutely have to be able to get to and deal with. And you want to attatch a big fitting with a piece of wire down the middle to a knob? Empirically I’ve never seen one fail. I’ve also not heard a lot of stories of them failing. But it would only have to be the once and you could get yourself in some deep doo-doo.

Never used one so can't comment, but if you never seen or heard of them fail, what's the problem?

The fact is however well intentioned your post is I feel it will only make some divers struggle to conform to the ''norm'' possibly putting themselves and others in danger if they are one of the 10% you quote.

I never try and ram my views down anyones throat if people ask I'll try to help, but the sad fact is some divers are fashion conscious and hearing Gods like yourself labelling them as part of a barrel chested, fat infirm bunch with ill fitting suits and no idea of style will not help them in the long term I fear.

Safe diving,
Steve

[Howard Payne]

Oooooooh he called my Digger a God AND he's a moderator - I'm proper proud I am.

What's definitely true in my experience is that a lot of people try a well thought out configuration or a piece of equipment (and I don't just mean DIR) and rather than persevering with it and mastering its use - they assume its not for them and change it for an easier option or they just add a convolution of their own which degrades the original design or very often is a poor substitute. Its more often a lack of familiarity and a need to acquire muscle memory or a new skill playinh head games with people, not that something is wrong, impossible or unachievable.

The six dive test and getting a mate to help you is a good one IMHO.

Undoubtedly some people can't reach their valves but it isn't many.

With Chasey it's all that Cossack hairspray on the big TV barnet that stops him reaching his isolator

[Woz]

100g undersuit- shutdowns no problem.
300g undersuit and thermals mid-winter- shutdowns no chance.

So in the summer I dive with the isolator open and can twiddle all day. In winter, I dive it shut. If I really really need to get at the knobs in winter then I hitch up the set, pull it over my head and do it with the knobs virtually in front of my face. Not elegant but it can just about be done.

Oh and before any clever clogs smart arse pipes up, no, I don't wear a crotch strap.

[Steve S]

Originally Posted by Howard Payne

What's definitely true in my experience is that a lot of people try a well thought out configuration or a piece of equipment (and I don't just mean DIR) and rather than persevering with it and mastering its use - they assume its not for them and change it for an easier option

Hi Jr
I agree in essence but there comes a time when perseverance must give way to reality, and despite all the advice to the contrary many people will never be able to shutdown quickly enough or indeed at all so either they stop diving or adapt their kit.

Originally Posted by Howard Payne

or they just add a convolution of their own which degrades the original design or very often is a poor substitute. Its more often a lack of familiarity and a need to acquire muscle memory or a new skill playinh head games with people, not that something is wrong, impossible or unachievable.

Not sure if your implying the degradation is inverting, or that it's a poor substitute there mate?
On a personal note the people I dive with and the diving I do is not bothered one iota by my lack of muscle memory or that rapid shutdowns upright are unachievable etc.

Originally Posted by Howard Payne

The six dive test and getting a mate to help you is a good one IMHO.

Undoubtedly some people can't reach their valves but it isn't many.

You are absolutely right and it was an experienced salt who told me I would never manage conventional shutdowns as long as I had a bum hole.

Originally Posted by Howard Payne

With Chasey it's all that Cossack hairspray on the big TV barnet that stops him reaching his isolator

That's not true it's the Hi Karate deodorant that sticks his armpit hair together thus restricting his movement

Safe diving,
Steve