BP/W for a New Diver

[TSandM]

Interesting . . . I'm 5'4" and small-framed, and I've never had a particular problem with an Al80, although I can feel the bottom of the tank on the back of my thighs when I'm diving. I use Tobin's stainless plate (or Kydex) and have never felt that I couldn't put my head back. DOUBLE Al80's are a different story!

 

[cool_hardware52]

Interesting . . . I'm 5'4" and small-framed, and I've never had a particular problem with an Al80, although I can feel the bottom of the tank on the back of my thighs when I'm diving. I use Tobin's stainless plate (or Kydex) and have never felt that I couldn't put my head back. DOUBLE Al80's are a different story!

I would suggest that because you are accustomed to diving doubles you are perhaps much less sensitive to having your head contact either the manifold cross bar or single first stage regulator on a singles rig.

For those concerned about head to reg clearance are a few ways to provide more clearance.

1) Adjust the height of the cylinder

2) Rotate the cylinder slightly, this shifts the reg from directly behind the head.

3) Get used to it. Really. My hoods have dent in them from being pressed in the isolator on my doubles. Some how I still manage to dive......

Tobin

 

[mahjong]

If you're feeling the tank bottom on the back of your thighs then perhaps you carry the tank very low (your top cam band locked down about as high up as possible). This might keep the reg low enough to be out of reach of the back of your head. But how you can arch your back comfortably I cannot quite imagine.

Interesting . . . I'm 5'4" and small-framed, and I've never had a particular problem with an Al80, although I can feel the bottom of the tank on the back of my thighs when I'm diving. I use Tobin's stainless plate (or Kydex) and have never felt that I couldn't put my head back. DOUBLE Al80's are a different story!

 

[mahjong]

The only way I could hit my head on my isolator knob is if I really go out of my way to lift my head far back. And if I did that often enough I suppose my hood might develop a "dent" in the back. However, it's one thing to bang the back of your head on your isolator knob when raising back your head; it's another thing barely to be able to raise your head because the regulator is that close to it. And I might note that I don't like the idea of banging my regulator at all, from a safety perspective. I know the reg is not going anywhere, but I just don't like banging it.

In any case, it's less than ideal to adjust tank height for other than trimming out right. Rotating the cylinder enough to make a difference might throw your hoses off a bit. And if one is going to "get used to" something, why not get used to an STA instead of to banging your head on your regulator?

I would suggest that because you are accustomed to diving doubles you are perhaps much less sensitive to having your head contact either the manifold cross bar or single first stage regulator on a singles rig.

For those concerned about head to reg clearance are a few ways to provide more clearance.

1) Adjust the height of the cylinder

2) Rotate the cylinder slightly, this shifts the reg from directly behind the head.

3) Get used to it. Really. My hoods have dent in them from being pressed in the isolator on my doubles. Some how I still manage to dive......

Tobin

 

[TSandM]

I think I have a dent in my HEAD from the manifold on my Mexico doubles . . .

I don't know how much other people arch their backs. I don't arch mine much; if I did, it would hurt. What I do is just tighten my buttock muscles enough to keep my knees from dropping. A single Al80 does not interfere with that at all.

 

[mahjong]

Well, come to think of it, it might be that I have a big butt, and not at all the kind of soft big that could possibly cradle a tank. My three-hours/day workout regime comes back to bite me in the butt again, this time literally. It usually gets me in the wallet, for alterations or custom cut drysuits. I'm 5'4", no fat, and thinsulate underwear is too tight in my legs with a stock medium-short TLS350, which is supposed to be cut for 400g.

In any case, is that an AL80 you're carrying in that picture? It's hard to tell for sure, but the neck looks longer than on AL tanks and the tank doesn't quite look 26" long, just barely reaching your butt and falling far short of your thighs. It looks trimmed out very nicely, though, not sagging like I imagined when you said you can feel it on your thighs.

I think I have a dent in my HEAD from the manifold on my Mexico doubles . . .

I don't know how much other people arch their backs. I don't arch mine much; if I did, it would hurt. What I do is just tighten my buttock muscles enough to keep my knees from dropping. A single Al80 does not interfere with that at all.

 

[cool_hardware52]

The only way I could hit my head on my isolator knob is if I really go out of my way to lift my head far back. And if I did that often enough I suppose my hood might develop a "dent" in the back. However, it's one thing to bang the back of your head on your isolator knob when raising back your head; it's another thing barely to be able to raise your head because the regulator is that close to it. And I might note that I don't like the idea of banging my regulator at all, from a safety perspective. I know the reg is not going anywhere, but I just don't like banging it.

In any case, it's less than ideal to adjust tank height for other than trimming out right. Rotating the cylinder enough to make a difference might throw your hoses off a bit. And if one is going to "get used to" something, why not get used to an STA instead of to banging your head on your regulator?

Nobody is advocating beating their head on a regulator, not sure why that red herring was hatched.

With doubles the cylinders are *much* closer to the diver, the cylinders are offset from the diver's back by essentially the thickness or the back plate, ~1/8" That places the Iso valve and cross bar much closer to the diver's head.

When I'm in trim and want to look forward my head is resting on the iso bar, and so are all of my teammates.

Many new doubles divers think they can't reach the Iso, but this is because they bend their neck forward when the reach for the valve. If they just put their hand on the back of their head and tip their head back their hand will hit the valve. That's pretty standard instruction for those new to valve drills.

With single tanks, even with a low profile back plate, the cylinder will be 1.5 ~2 inches further from the divers back than with doubles. Combine that with a bit of minor tank height adjustment or a few degrees of cylinder rotation and there is enough clearance for most, certainly most of my customers anyway.

Diving involves adapting to lots of new things, and more hardware is not always the answer.

Tobin

 

[mahjong]

I've only been diving doubles for about 11 months. And my tanks are 20.5" MP72's (I also have a rig with 1800psi 40's, but these are also about 20" long). So at least with these short tanks I have had no problem with my head hitting the isolation knob, and I keep it tilted a tiny bit towards my head, though I can give it a knock with my head if I really try to. Notwithstanding, I can certainly see how the isolator knob can be a nuisance on many a doubles setup.

I'm now holding an MK10 in one hand and a ruler in the other. The reg protrudes about 2.375" from the tank valve. And then there are the hoses coming off the turret. And some regs have a higher profile than the MK10. If one keeps the isolator knob straight up, I would say that the reg on most single tank setups will still be closer to the diver's head--and certainly the reg with hoses protruding is a bulkier bulge back there than an isolation knob.

Yes, I know a bit about diving and adapting, precisely because I am a compulsive tinkerer. I have come to the conclusion that, no matter how much I might fuss to make things perfect, there's always something unexpected or new that requires accommodation or adaptation.

Here's what hatched the red herring for me: "Get used to it. Really. My hoods have dent in them from being pressed in the isolator on my doubles. Some how I still manage to dive......" ;-)

Nobody is advocating beating their head on a regulator, not sure why that red herring was hatched.

With doubles the cylinders are *much* closer to the diver, the cylinders are offset from the diver's back by essentially the thickness or the back plate, ~1/8" That places the Iso valve and cross bar much closer to the diver's head.

When I'm in trim and want to look forward my head is resting on the iso bar, and so are all of my teammates.

Many new doubles divers think they can't reach the Iso, but this is because they bend their neck forward when the reach for the valve. If they just put their hand on the back of their head and tip their head back their hand will hit the valve. That's pretty standard instruction for those new to valve drills.

With single tanks, even with a low profile back plate, the cylinder will be 1.5 ~2 inches further from the divers back than with doubles. Combine that with a bit of minor tank height adjustment or a few degrees of cylinder rotation and there is enough clearance for most, certainly most of my customers anyway.

Diving involves adapting to lots of new things, and more hardware is not always the answer.

Tobin

 

[cool_hardware52]

I've only been diving doubles for about 11 months.

Here's what hatched the red herring for me: "Get used to it. Really. My hoods have dent in them from being pressed in the isolator on my doubles. Some how I still manage to dive......" ;-)

You suggested people were banging on their regs, and that's just unnecessary.

I tinker with dive gear for a living.......

I've been diving doubles for many years, and so have my teammates. Head resting on the Iso is pretty much SOP for all of us. It's just not a problem.

Tobin

 

[mahjong]

"I tinker with dive gear for a living......."

You hiring?

You suggested people were banging on their regs, and that's just unnecessary.

I tinker with dive gear for a living.......

I've been diving doubles for many years, and so have my teammates. Head resting on the Iso is pretty much SOP for all of us. It's just not a problem.

Tobin