>Nigel wrote
>> I'm unconvinced about Single Tank Adapters on twinset
>> plates. I don't see the point.
>
> There is a lot more to DIR than where you hang your gear.
That's what they all say.
> Using a SS backplate you move a lot of your weight further up your
> body
Woo. Stop there. My plate weighs 2.4 kilos. The center of the plate isn't
more than six inches above my waist so it's effect on my trim, compared
with 2.4Kgs on the belt, is negligable.
> which makes it easer to keep horizontal in the water, which is a
> much better swimming position.
So on the single I adjust this by where I put the cam band round the tank.
I was taught this in OW.
> This does not happen with an AL BP
> which is why they are only recommended (well actually thay are not
> really recommended at all) for tropical diving where it is assumed you
> are not going to be wearing much weight.
I thought the reason for a plate was as a jumping off point for the 5 point
harness which allows the rig to be attached to you with nothing tight.
Then it also does a weight distribution job to prevent a twinset twisting
and digging into your back when out of the water by putting the force
against the big bones of your pelvis not into the soft muscles of your back.
Certainly that's what Bill Main seemed to think when he introduced it.
> Of course, this may not bother you, so if it doesn't... don't worry
> about it. It does bother me though, so my girlfriend is inheriting my
> Buddy Franken Wing (16kg buddy travelwing-a-like made from parts) and
> I have a nice new single tank wing which arrived yesterday.
Now I am perplexed. Couldn't you fix the old wing on a plate?
Don't tell me. It's a Halcyon?
However you are clearly made of sterner stuff than I am. If I had ever
said to one of the girls in my life "This isn't good enough for me. You
can have it and I'm getting a new one" it would probably have cost
me blood.
nigelH
Simon - 28 Jan 2004 23:23 GMT
<snip>
> Woo. Stop there. My plate weighs 2.4 kilos. The center of the plate isn't
> more than six inches above my waist so it's effect on my trim, compared
> with 2.4Kgs on the belt, is negligable.
So, having half your weight further up your back than your waist will
not effect your trim?
> So on the single I adjust this by where I put the cam band round the tank.
> I was taught this in OW.
That's another part of the equation, but with the Buddy I had the tank
about as high as I could reasonably get it I was still not as
horizontal as I wanted. And, your solution to this would be...
> I thought the reason for a plate was as a jumping off point for the 5 point
> harness which allows the rig to be attached to you with nothing tight.
> Then it also does a weight distribution job to prevent a twinset twisting
> and digging into your back when out of the water by putting the force
> against the big bones of your pelvis not into the soft muscles of your back.
> Certainly that's what Bill Main seemed to think when he introduced it.
This may be(?), however we were dicussing the difference between AL
and SS backplates, not the reason for having a BP in the first place.
> Now I am perplexed. Couldn't you fix the old wing on a plate?
I could have... and this will more than likely happen in the future.
At the moment we have a SS BP and a backpack. I could have said f@ck
off and buy your own, but since she has been borrowing it for ages,
and likes it, I gave it too her.
> Don't tell me. It's a Halcyon?
Nope. http://www.blackart.com.au.
>much better swimming position. This does not happen with an AL BP
>which is why they are only recommended (well actually thay are not
>really recommended at all)
This is not true. Most if not all of the GUE people recommend that
you use an Al. backplate and Al cylinders if diving with a wetsuit
and 'doubles' in the sea.
Pete

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"Just another crouton, floating on the bouillabaisse of life"
Simon - 28 Jan 2004 23:34 GMT
> >much better swimming position. This does not happen with an AL BP
> >which is why they are only recommended (well actually thay are not
[quoted text clipped - 3 lines]
> you use an Al. backplate and Al cylinders if diving with a wetsuit
> and 'doubles' in the sea.
Do they? Who?
Even if they do, they would also recommend a drysuit over a wetsuit
for doubles, even in the tropics.
The reason for all these recommendations is to have a balanced rig
i.e. not overweighted and good trim. To quote, more or less, Andrew
Georgitsis from my DIRF course "Having good trim is the root of DIR".
Pete Melbourne - 29 Jan 2004 08:02 GMT
>Do they? Who?
Page 70 of Doing It Right by JJ
Pete
diving 'at' melbourne 'dot' me 'dot' uk