Back inflation BCD

[dmoore19]

I have a jacket style BCD. I recently purchased a Zeagle Stilletto. I intend to keep it for backup or as a loaner, I really like it but wanted to try something with different characteristis. I did my research and talked to my LDS for several weeks prior to the purchase. The reasons I purchased the Zeagle were 1) I am strictly a warm water recreational diver and wanted something to help with trim. 2) I like integrated weights, as my wife says I have not butt. I tried a belt a couple of times and just couldn't get the thing to stay put. 3) Contrary to many of the posts here my LDS gave me a good price (less than the online retailers, I checked before buying) 4) I have had back surgery and find that I like the idea of the padding that the Zeagle has 5) I will not be doing any Tech diving, just floating around photographing and looking at the pretty fish and corals. 6) It is lighter than my Seaquest BCD jacket style and takes up less room when packing to travel.

The reason I say this is it suits my needs, provides me with similar trim qualities to a BP/W and has padding in the back for my tired old bones. BP/W may be ideal but I think there are many things to consider. I know that I don't have that many dives but I gave a lot of thought to my decision and I think everyone should. If BP/W were the perfect solution for all divers BCs wouldn't be manufactured for long because no one would buy them. It is a personal decision and everyone should do what best suits their needs.

Having said that, I will be doing some pool sessions to make sure I understand the differences in the 2 BCs. I read here that 10% of the weight added should be put in the trim pockets. I dive with a 3mm full suit with boots and no hood, Tusa extreme zoom fins and a single AL80. Do any of the other parts of my geaf change the 10%

 

[meierdierck]

i hate to detract from a good debate, but here is my 2 cents on the OP

I dive a Genesis recon back inflate, love it, like driving a cadillac compared to any bcd I have ever tried, cant say enuf good things about it, BUT on the surface it sucks, maybe it is the way it is made because I have tried everything to make it better, and I hate it for surface, I have to arch up on top to stay afloat, and that gets tiering quickly, for my own personal diving, it is awesome, for teaching, with alot of top side talking, etc. I would not recommed

I have a Scuba pro Glide just for teaching, I dont like it for anything else, and the only reason I use it is specifically teaching, I float comfortably,, and can talk to my students without fighting to keep my face out of the water, and it is what we have in rentals so it does make demonstrations easier with newbies....vs this is how mine is, yours is different,

I also have bp/w, but that is irrevevalt to this thred...

hope this helps, back to the debate...

 

[halocline]

Trim underwater is determined primarily by weight distribution, not whether the bladder is a back inflate or jacket style. Since the bladder is not full underwater (except in extreme, rare cases) the air bubble just rises to the top regardless of the bladder's shape.

When OW students are kneeling on the bottom (that's a whole different discussion) they typically have little or no air in their BC, so the comment about back inflates pushing them forward is incorrect. However, putting weights in the back pockets or towards the back in some other way, suggested by the same person I think, is a good way to help those students stay upright while kneeling on the bottom.

 

[meierdierck]

Correct me if I'm wrong but isn't the Recon's bladder design very similar to a wing?
QUOTE]

your correct, the recon is 100% bp/w knockoff, totally tec wana-be, but in its defense, it is almost as comfortable as a bp/w, and it has help up amazingly well, considering, IMO.

 

[meierdierck]

Trim underwater is determined primarily by weight distribution, not whether the bladder is a back inflate or jacket style. Since the bladder is not full underwater (except in extreme, rare cases) the air bubble just rises to the top regardless of the bladder's shape.

When OW students are kneeling on the bottom (that's a whole different discussion) they typically have little or no air in their BC, so the comment about back inflates pushing them forward is incorrect. However, putting weights in the back pockets or towards the back in some other way, suggested by the same person I think, is a good way to help those students stay upright while kneeling on the bottom.

but the style of bcd will determine the distribution, with back inflate I tend to shift weight to the front/ middle like a ballast, with the jacket it is more distributed around, like a weightbelt, and I have noticed more of our divers tend to use ankle weights with jackets than bak inflate, again I guess it would be up to the individual.

I dont think the op is putting these on students, but now I am curious, do many shops use back inflate on students, I have taught at quite a few different stores/ shops, and from what I have seen scubapro glide seems to dominate the rentals, at least on the left coast, what are other locations using for students?

 

[RAWalker]

mattboy the forward push comment was about the back inflator style overinflated at the surface. Although the best fix for this is simply to let some air out and just float the divers head and not try to get higher out of the water. Adding weight in the rear trim pockets will also help keep the diver more verticle while allowing a bit more inflation and height out of the water.
I agree trim is a matter of distribution that is why beyond suggesting 25-33% of the weight being placed in the back trim pockets I also reminded readers that moving the tank will effect trim.

 

[dmoore19]

My last post was an attempt to facilitate peace. This thread was getting pretty rough.

I am glad to have professionals available to ask questions and advise. I know I am just an infant when it comes to my Scuba knowledge. I am greatful for the possibility of having experienced people help me with my decisions. Everyone here has an opinion on everything. I am greatful for this. DevonDiver, I appreciate your opinion. RAWalker I appreciate your input. I think I made a decision based on good information. I may have made a mistake buying the back-inflate but I think the decision was based on reliable information. I may have made a mistake but I will deal with it. If it was a mistake I guess I will either have more unused equipment to take up room. I may end up having to sell what I have (at a loss) and go to a BP/W. Guess I won't know until I try it for sure and find out for myself.

THANKS for everyone's help.

 

[DevonDiver]

Glad you found the thread useful, and I hope you benefit from the various opinions stated on here.

If the BCD you bought suits you now...and you are happy with it.... and happy that it is a finite solution to your diving needs, then it worked out great for you. I do think (with the benefit of personal experience) that your diving will eventually lead you towards a proper BP/W set-up. However, even if you sell your current bcd at a loss, it is a small cost for the pleasure of getting in the water and enjoying exploring the sub-aquatic world.

The issue of rear inflate bcds 'pushing forward' at the surface is a very real one. In tropical climes it can be countered by not 'over-inflating' the bcd. If you are diving in colder climes, with more weight..and steel tanks... then you will have to put more air in the bcd to maintain positive buoyancy on the surface....thus, will be pushed forwards.

Some of the posted 'solutions' to dealing with this inherent design failing with hybrid 'wings', do not seem to be based on sufficient experience, as they have only used the bcds under one particular set of conditions/circumstances and have failed to consider every/other situations.

That was my personal experience of diving with a hybrid rear-inflate bcd. I didn't 'over-inflate' it... but to put sufficient air in the bcd to keep my head clear of the water at the surface (wearing steel tank and weighted for drysuit) always meant I was being pulled head first forwards/down. I hated that characteristic of the hybrid design.

The same effect was not apparant with a proper BP/W due to the crotch strap and distribution of weight through the backplate.

The primary (safety) purpose of the BCD is to provide ample positive buoyancy at the surface, in order to float you head-up and clear of the water - without effort, strain or energy. If a BCD doesn't do that, then it is failing in one of its major tasks. In an emergency, having to dump air from a BCD, in order to prevent drowning, is illogical and a senseless 'fix' for a problem that shouldn't exist in the first place.

IMHO, most of these hybrid 'wings' are just a marketing ploy, aimed at inexperienced divers - who like the idea of looking 'technical', but have insufficient knowledge to truly ascertain what benefits and drawbacks the quasi/hybrid designs are offering. It's one of the reasons why many of these hybrid designs are marketed with the word 'Tech' somewhere in their name. They aren't technical diving equipment.... but are marketed as such.

Technical diving has provided many 'best practices' that are gaining favor within the recreational diving industry...and it is entirely logical that many recreational divers would look towards technical divers as a source of knowledge to improve their skills and equipment configurations. However, these 'hybrid' wings are an attempt to cloud the issues.... offering the illusion of being a technical 'best practice', but coupled with a reluctance to fully divorce from the standard jacket bcd formula (basically, a calculated grasp on the insecurities of novice divers).

As I stated initially.... these 'hybrids' offer all of the drawbacks of regular jacket bcds, but few (none) of the intrinsic benefits of a true, modular, BP/W configuration.

I never, ever, stated that people shouldn't buy these hybrids...and neither am I inclinded to sensationalize the issue by stating "they're gonna kill you" or tripe like that. I just want to point out that a hybrid bcd won't offer you the benefits of a BP/W.... if you thinking that they will.

 

[RAWalker]

Not all the Hybrid Back Inflators are marketed as tech oriented.
Some are just well made recreational diving BCD as 1 example Sherwood does not even suggest in it's advertizing that the Tortuga is tech oriented and I can think of a half dozen other Hybrid style that make no such claims.
Then there are those that do make those claims such as some of the Hollis and Zeagle products.
These are not bad products in fact they are very high quality products that make certain trade offs to add features and comfort. Whether these trade offs fit your needs and requirements only the individual user can decide. Manufacturers have marketed these features or trade offs in a progressive manner some strictly recreational and stretching across the board to highly technical. Only you can decide what best suites your needs.
To say that every diver will eventually be lead to a BP&W is foolish it simple doesn't meet the needs and requirements of many divers.
Dismissing the product sector is simply foolishness that shows a narrow minded individuals shortcommings.
I have logged dives in Cold water fresh and salt in 7mm of neoprene and other dives that ranged down to just a swimsuit. My wife used the same BCD a year ago in Cancun and we had 3' of chop at the surface while waiting on our boat to spot us and pick us up. She was more far comfortable than I was using my BP&W.
Yes, I'm sure that there are some models that faceplanting is more of a problem but when properly weighted and inflated it isn't a issue at with most models.
The closest I will come to agreeing with DevonDiver is to say if your diving is headed towards technical diving or even just doubles in the future then is would probably be best to skip a technical oriented back inflator BCD and start looking at a BP&W.
If not then you have a world of good choices to find what fits your needs best.

 

[dmoore19]

I went to the pool today. I was able to change weight as far as amount and position using the weight pockets and the trim pockets. I spent about and hour messing around with these and getting things figured out as far as trim underwater and how to keep my face out of the water on the surface. It was wonderful. The Zeagle Stiletto was great. I ended up with 3 lbs in each pocket with nothing in the trim pockets. I tried different combinations with and without trim weights and this worked best for me. I know this is fresh water but it should be similar in saltwater (I think). the weighting was simple and easy to do. Much easier than the jacket BC I used before. (sea quest Latitude). My Boyancy was great and easy to maintain even in<10 ffw. I am extremely pleased with the purchase. I am really looking forward to using it (really hoping) in Cozumel in November. Or (and?) Roatan in December. I am really excited about it. It made a world of difference as far as the stability of it, the comfort of it and the way I was able to control my boyancy with just a little bigger breath or a little smaller breath. Amazing!! Wonderful!! When at the surface I simply adjusted the air and leaned back and was quite comfortable. I could also remain completely vertical and keep my head above water with no problems. For me I think this will be a long relationship with this BC! If my needs ever change I will check out the BP/W but for now I am really pleased with the performance of this BC. Might give my SeaQuest to my daughter to use as a beginner. I think she is going to try to start a class at college if it is available there. I found out today it can be a class with college Credit Hours to boot. Looks like a Win Win situation to me, except I will be the Bank of Dad when she does it. Oh well, if this is the cheapest thing she pursues I will be lucky.

Thanks for everyones help.