BCD vs BP/W

[Walter]

This brings up a question I've had based on comments here.

People always seem to say something like "I got a steel backplate and/or a steel tank and now I only dive with 2 pounds of lead" or whatever.

They say it like the weight is actually gone -- like they're literally diving with less weight. But really its just the same weight in a different form.

I mean is it really surprising that if you strap a big steel plate to your back you can take a corresponding amount of weight off your belt?

So what part am I missing?

If you switch from a BC (BP/W - vest - back inflate - doesn't matter) with padding to a BC (BP/W - vest - back inflate - doesn't matter) without padding, you'll drop lead. Often, you can go to a lighter BC and still drop lead. All that padding has weight. My BC (vest) has no padding and no cummerbund, it's very light weight, but when I dive a ST 72 I don't need any lead even in salt water.

 

[lamont]

I'm basically trained by my job to think in terms of failure points, engineering for simplicity and single purpose tools that work correctly every single time over a large scale. The BP/W design scratches that itch. All it does is serve as a buoyancy compensator and hold your tanks. It doesn't have a lot of pockets or integrated weights and other stuff, particularly any plastic stuff or glued things that can break. The backplate itself is going to be just about indestructible. The webbing is easily replaced when it starts to fray. The d-rings and stainless hardware is similarly available and pretty much indestructible. If you get one with an inner bladder design then you've also got a highly puncture resistant air pocket, and if its hogarthian it should only have a single hole in the top where the inflator hose connects and a single dump on the bottom, minimizing failure points. Based on the design I'm just about positive that I'm never going to have to send one back to the manufacturer, and it also gives me warm fuzzies about its integrity when I'm actually underwater -- which is important now that I'm going into tech diving -- but before I made that decision I still liked the design.

I also don't like the general idea of having an air bladder that goes around the diaphram. I tend to view that as a bit of a design flaw in the standard BC. The back-inflates like the Zeagles are fine BCs, but if you read here:

http://www.calvintang.com/blog/2005/08/zeagle-stiletto-bcd-review-light-and-easy-with-a-few-hangups

The issues with the integrated weights and the adhesives are precisely the things that I don't want to deal with over time. With a BP/W you'll need to replace the webbing, you might need to replace a dump valve (easy to source, and my lift bags have the same valve, so its actually repairable underwater), you'll need to replace your inflators and hoses, and in the worst case you might tear the bladder, but these are issues that you simply can't get away from.

 

[kidspot]

3 primary reasons I went with a BP/Wing over a standard Jacket (yes - both are BCD's)

1) Comfort: For the first half of my Open Water course I was in a jacket ... then switched to a BP/W with Hogarthian Harness - it was like taking a suit coat off and putting a t-shirt on - MUCH more comfortable for me, both in and out of the water, but especially inwater.

2) Stability: I really didn't like the way the tank slid around on my back using the Jacket variety BCD. I have tried 3 different jackets, and the tank moved a lot on all of them. With my BP/W BCD it is rock solid on my back. I have tried 4 different plates/wing combinations and found this to be true on all of them.

3) Future: I kept coming across the idea that early on any BCD is fine, but "if" you end up going to doubles or doing tech dives you will "need" a BP. No one had a good reason not to start with a BP, and it made sense that if I ever went to doubles or tech diving I wanted to be familiar with the gear as much as possible... so why not start in a BP.

I've not regretted starting in a BP/Wing BCD. And every time I borrow a Jacket to try I am reminded why I like my BP so much better. 90% of the time, I'm the only BP/Wing diver in the group, and get a lot of questions as well as the occassional "tech wanabe" comments, but I'm happy and comfortable...

Does everyone agree with me that a BP is great? Nope ... does that matter ... nope...

Aloha, Tim

 

[cummings66]

One thing is certain, around here I'm not likely to have somebody confuse my gear for theirs. BP/W's are not real common but I'll usually see one or two every time I go diving at TableRock. Of course we're out numbered but we seem to have fun regardless of the status.

One thing bugs me however, for some reason everybody assumes a BP/W is tech gear and although it can be it does not need to be.

 

[TSandM]

Oh, but a BP/W makes the slide into technical diving so EASY . . . says the woman who wasn't sure she wanted to learn to dive in the first place, and is now trying to decide whether Tech 1 or Cave 1 comes first

 

[TheRedHead]

Just unbolt the STA and bolt on the doubles, honey!

 

[serambin]

There are a couple factors.

The first is the inherent buoyancy of many jacket BC's. By this I mean the weight required to sink just the BC when the bladder is empty. Often this can be 3-5 lbs or more. It's the pads and cumberbuns. A Hogarthian Rigged BP&W has no such buoyancy inducing fluff. Floaty BC's need more weight

The second is related to ease of venting. If your BC is hard to vent, you carry extra weight.

The remaining reason is a bit less obvious. Good horizontal trim, which is often easier to achieve in a BP&W means continuous finning to offset being too heavy is ineffective. Once Divers learn to hover, more or less motionless, they find they need less weight.

Regards,


Tobin

While some BCD's may require additional weight, most do not. They are designed to be neutral in buoyancy. Mine certainly is.

On a quality BCD's, multiple vents allow equally effective venting.

Here are the positives for BCD's over BP/w's:

1. Less expensive.
2. More comfortable, especially after four days of shallow three tank dives.
3. They allow for more flexibility in distributing weight for trim.
4. For extented periods on the surface, BCD's require less effort to float in a heads-up position.

MHO,

Stan

 

[Freds@Aquanauts]

Thanks for all you guys posting your different opinions, I really was asking a genine question, as I'm always like to get both sides of a story regardless of the situation. I cant imagine anything being mroe comfortable than my Vector 1000 mrs, and had no intention of ever using a BP/W unless I was going to do Tech. However since I've been on SB and seen how many people use BP/W for recreational diving when I go back to thailand in September I will definately be trying one out for a week or so! Glad you can get plastic BP's though, I only use 1.5Kgs, and thats when I'm DM'ing a class, so with SS or AL I may well never come back up again!

Freds

 

[TheRedHead]

1. Less expensive.

Possibly, but not always true.

2. More comfortable, especially after four days of shallow three tank dives.

Not in my experience. BCs are more saggy and make my neck hurt.

3. They allow for more flexibility in distributing weight for trim.

Definitely not true. I can bolt on weights, change the weight of my BP and use pockets to put weight anywhere.

4. For extented periods on the surface, BCD's require less effort to float in a heads-up position.

Doesn't take any effort to float in mine. I can even make into a Barcalounger if I wish.

 

[*Floater*]

Here are the positives for BCD's over BP/w's:

1. Less expensive.
2. More comfortable, especially after four days of shallow three tank dives.
3. They allow for more flexibility in distributing weight for trim.
4. For extented periods on the surface, BCD's require less effort to float in a heads-up position.

MHO,

Stan

Hmmm, your list makes me wonder whether you've ever tried a BP/W setup...

Anyway, I went with BP/W because that's what all the experienced divers here seem to use so I figured there must be something to them and also I didn't want to have to buy another BCD for tech/cave diving, let alone travel around with two of them. Of course I now have to travel around with two wings, but they don't take up much space or weigh much.