Choosing a Backplate and Wing

[bvbellomo]

I've found a lot about Hogarthian diving principles, but little specifically about what a 'Hogarthian style' harness is verses something like the dgx (should I call it a "standard harness" or "non-Hogarthian harness"?).

Is the difference just the ability to adjust the straps? I like adjustable straps if I am using a variety of wetsuits, and snugging up straps after getting into gear can lead to a tighter fit which might be better with a heavier tank.

It seems like getting a dgx with an aluminum plate is the way to go, but I'd rather understand and read more - especially since I won't get a chance to dive for a while.

 

[lowwall]

I am 6 foot tall, so I doubt I need a long, but that and chest/shoulder size is enough to prevent sizing down the Axiom.

Dropping 2kg immediately puts me at 6kg. That wetsuit is probably close to 8kg buoyancy, and I will do few, if any, dives in the Red Sea, and some in freshwater. So I am potentially negatively buoyant with an aluminum plate and no weights at all, I am not sold on adding 2kg to my back and compensating with more air.

Where are you going to be diving? I'm asking because your location says United States and you are highly unlikely to find 15 liter AL tanks in the US or in the Caribbean. Or SE Asia for that matter.

You will definitely need weight diving the standard warm water tanks in all those places which are AL80s (10L) or the normal larger option of an AL100 (13L).

But if you can find an operator which offers steel 120 tanks (or if you buy your own), you are probably correct that you would be overweight with a steel backplate and no exposure suit. You would be close to neutral with a steel 100.

 

[runsongas]

Dtd or tecline bpw if you prefer a euro brand than deal with importing from dgx. Or even a xdeep zeos.

 

[bvbellomo]

Where are you going to be diving? I'm asking because your location says United States and you are highly unlikely to find 15 liter AL tanks in the US or in the Caribbean. Or SE Asia for that matter.

I'd like a Backplate and Wing that I can use all over the world, although I have no interest diving below 10C. My most recent trip was Egypt. I might never use this specific type of tank again, just mentioning it was much bigger problem with a heavy tank, and I might want a bigger tank in the future too unless I can improve my SAC rate.

You will definitely need weight diving the standard warm water tanks in all those places which are AL80s (10L) or the normal larger option of an AL100 (13L).

But if you can find an operator which offers steel 120 tanks (or if you buy your own), you are probably correct that you would be overweight with a steel backplate and no exposure suit. You would be close to neutral with a steel 100.

That's a big assumption about my body given just the information on this thread, but even if I never end up negatively buoyant, I feel safer with more droppable weight.

 

[lowwall]

,

I've found a lot about Hogarthian diving principles, but little specifically about what a 'Hogarthian style' harness is verses something like the dgx (should I call it a "standard harness" or "non-Hogarthian harness"?).

Is the difference just the ability to adjust the straps? I like adjustable straps if I am using a variety of wetsuits, and snugging up straps after getting into gear can lead to a tighter fit which might be better with a heavier tank.

It seems like getting a dgx with an aluminum plate is the way to go, but I'd rather understand and read more - especially since I won't get a chance to dive for a while.

Standard and hogarthian is the same thing. The harness is one continuous loop of webbing except for the crotch strap. The alternative is called a deluxe or comfort harness. It usually includes some padding and shoulder clips and maybe a chest strap. It's basically a BCD style harness except with a standard waist strap instead of a cummerbund.

They appear attractive if you haven't used a standard rig. But the truth is that a standard rig is easily adjustable and normally more comfortable. All those extra clips and straps are potential irritation points, while with a conventional harness the load is always spread over a 2" wide belt.

I made the mistake of getting a deluxe harness with my first backplate. I suffered from having the overly complex chest connection mechanism digging into me for years before I ditched it for a standard rig. I'm much more comfortable now. That said, some people simply can't move their arms in a way that needed to exit a standard rig. The easiest solution is to add a clip to make a shoulder break on one side of the harness like most BCDs. Once one arm is out, it's easy to get the other one free.

 

[lexvil]

Many of your presumptions are incorrect and most have been addressed in previous posts but two things, one you will be much better off in every situation with a steel back plate, two any expection of moving”gracefully” with all of the stuff strapped to your back should be set aside as not tipping over is about as graceful as it gets.

 

[drk5036]

Dropping 2kg immediately puts me at 6kg. That wetsuit is probably close to 8kg buoyancy, and I will do few, if any, dives in the Red Sea, and some in freshwater. So I am potentially negatively buoyant with an aluminum plate and no weights at all, I am not sold on adding 2kg to my back and compensating with more air.

I have no idea what you’re trying to say here.

You said you need to use 8 kg of weight with your BCD right? Going to an aluminum backplate means you’ll probably need 5-6kg of extra lead. A steel plate maybe 4. Not sure where you think you’re dropping 8 kg from…

 

[lowwall]

That's a big assumption about my body given just the information on this thread, but even if I never end up negatively buoyant, I feel safer with more droppable weight.

There's no assumption, you told us how much weight you needed with a 5mm and two different tank sizes. Given a baseline setup, you can come within a kilo of the correct weight for other setups unless you are throwing drysuits or very thick wetsuits into the mix. FWIW, my weighting requirements are similar to yours and I've used a steel 120/15. Yes I was about 1 kilo overweight in a 3mm shorty and my steel BP at the end of the dive. But I could still swim it up easily at the beginning even with no air in my wing (I tried it), so I wasn't worried about it.

The other advantage of a steel BP is trim. Your mention that you have difficulty staying horizontal. For nearly everyone that means the feet tend to hang down. A steel plate has weight up high to counteract that tendency. With a BCD or aluminum plate with weight pockets or a weight belt, that weight is going lower, which exacerbates the issue. If you do go with an AL plate, you can somewhat compensate for this by getting a couple of trim pockets and placing them on the sides of the upper cam band next to the plate. A 1 or 2 kilo weight in each pocket will help you start in trim.

 

[lowwall]

I have no idea what you’re trying to say here.

You said you need to use 8 kg of weight with your BCD right? Going to an aluminum backplate means you’ll probably need 5-6kg of extra lead. A steel plate maybe 4. Not sure where you think you’re dropping 8 kg from…

That was with a 5mm suit. He's talking about his weight need with a rash guard only.

It took me a couple of re-reads to figure that one out too

But yes, out of all the possible single tank configurations, he's fixated on the one - big steel tank and no wetsuit - where an Al plate would be preferable to an SS plate in the water.

 

[gqllc007]

I would go and did go SS over Aluminum as well..few people are negative buoyant with an aluminum 80 and no weights. Otherwise if he was going to do steel 120 then I see the benefit to aluminum but not much otherwise