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SeaJay

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(Name witheld) wrote on 10-20-2002 02:25 PM:
whts a fred t bp/wings ???

who makes the transpac ??

thnks


Ah... :D

Glad you asked me instead of asking on the board. Both of those two that you're asking about are types of buoyancy control devices, and there's many people who are very passionate about one or the other. Asking anyone, anything about BC's is like asking, "What's a Ford?" or, "What's a Chevy?" It wouldn't be as scary as if someone asked, "What's better... A Transpac, or a bp/wing?" But it's close enough to start a small war on this board. :D

I don't know how much you know about this stuff, so I'll try to give you a synopsis... A backplate and wings, shortened to, "bp/wing" is actually a metal plate that straps to your back, and which has a bladder connected to it which can be inflated or deflated to control your buoyancy. A diver would wear a bp/wing instead of a BC jacket, which you're probably already familiar with. There are certain advantages and disadvantages to each design... A jacket BC, which you've probably used in some scuba classes, does a nice job of being easy to handle, short and sweet to connect to a diver, and rarely has a problem holding the diver any which way that the diver wants to be. There are some that believe that jacket style BC's have the tendency to hold divers in a head-upright position, which is just what is needed at the surface when you're treading water... But not what you want when you're swimming underwater (instead you would want your body horizontal.) My personal experience is that there is some truth to the concept that generally, jackets have the tendency to hold a diver head-up at the surface, but that the tendency to do so can vary widely from design to design... So just because it's a jacket-style BC, does not necessarily mean that it will do so. In fact, the US Coast Guard has specifically stated that most BC's are NOT legal life preservers because they DON'T hold a human head-up enough at the surface.

An alteration to the jacket-style BC is the "back inflate" BC... This is a relatively newer design (jackets have been around since 1972) that do not blow up the whole jacket... Instead they have a bladder on the back of the diver (usually around the tank in an upside down "U" shape or an "O" shape). These have the advantage of getting the air cell off of the diver's chest, making the diver feel less claustrophobic and less like the Michelin Man at the surface. Unfortunately, this type of design has the tendency to create a new problem... Because the cell is now only on the diver's back, a fully inflated cell at the surface has the tendency to push the diver face-forward. This isn't impossible to overcome with a gentle kick back into the bladder, and some have found that the tendency is reduced if they don't inflate the cell too much. There are other ways of combating the problem, too... By placing weights on the tank itself, or merely by placing the weights "far back" on the waist. Admittedly, people who properly "dial in" their weights have less problems with the face-forward issue at the surface, and some go so far as to use tanks made of different materials that simply weigh more in the water, bringing the center of gravity back and helping the diver not to have to battle the "face forward" syndrome. When all is said and done, someone who's properly "trimmed" themselves in the water enjoy much less clutter on their chests, where it can be most annoying, while not having to deal with the "face forward" syndrome.

The backplate and wing is the ultimate back inflate BC... It simply consists of a metal plate (it's small, typically 12" x 16" or so) that is held in place by a variety of available straps, called, "webbing." Some people do their webbing one way, some do it others... But by far the most popular way is the "continuous" way, which is one long piece of 2" webbing that is threaded through the backplate in such a fashion as to create arm holes and a belt. Another piece is then added which goes from the bottomost part of the plate, through the crotch, and connects to the diver's belt in the front. An air cell is added to the backplate, creating a back inflate BC, and then a tank is added over the cell. This has some advantages and disadvantages too. The advantages are that if anything cuts or maims your webbing, you can replace it for about $5. Your chest area is now completely minimalized, with almost no buckles, D-rings, or anything else. This system, while lacking a little bit of comfort on land (since it's a hard plate) nearly disappears underwater. Backplates are nearly indestructable compared to any other kind of BC. Backplates are known for their stability underwater, too... Simply put, once they're on and fitted properly, they don't allow the tank to move at all, which can be really annoying by dragging out of the water or hitting you in the head as the tank empties and gets lighter. There are a variety of pockets, rings, wings, weight systems, etc. that can all be added or taken away from the "rig," making it by far the most versatile of the three basic designs. The disadvantages are that pull dumps on these systems are either nonexistent or worthless, you pretty much have to wear a crotchstrap (which bothers some and not others) because of the unit's lack of internal structure, and basically, you need to assemble and adjust the rig yourself. You're also going to get a lot of flack from uneducated divers, asking, "What the heck is THAT thing??" You'll also find that while a bp/wing is wonderfully adjustable to fit any body type in any situation, it is not adjustable "on the fly" while it's being worn. For this reason, it can be a pain and is not really suitable as rental gear. But the biggest disadvantage is that like back inflate BC's, while it "cleans up" your chest area and feels like it minimalizes your gear, all that's really going on is that you're moving things behind you... Which isn't the balanced point... So now trim becomes an issue, which must be addressed. Which is why you'll find so many conversations about trimming on this board, or what tank weighs what, or where to place your weights, or swimming without any ditchable weight, or whatever. Oh yeah... Another odd characteristic about backplates and wings... Since there's a metal plate in there, it already has some weight to it. Most consider this an advantage (since you can now take some weight off of your waist) but it can be seen otherwise, too... I mean, if you were a lost diver at sea, and having to float indefinitely, wouldn't you want to be able to ditch ALL of your weights?

Anyway, the bottom line is that we are all after the same thing... We want a system that will never fail, is easy and cheap to replace parts on, will hold everything that we need, and still not make us look like Christmas trees with stuff hanging all over the place. Generally speaking, jackets tend to hold you upright nicely at the surface, but tend to hold you upright in the water too, which isn't what you want while swimming. Generally speaking, back inflate BC's and backplate/wings both tend to push you face-forward at the surface, but tend to allow you to swim more horizontally in the water, making you swim faster with less effort, allowing you more time underwater (less air used) covering more ground. Both jacket style BC's and back inflates and bp/wings can be "trimmed" to tune out any unwanted characteristics, although jackets tend to not react as much to trimming, while back inflates and bp/wings tend to react very much to trimming. Ultimately, though, we're all looking for the same thing... A system that is completely neutral in all cases. We want to CHOOSE to be head-up when we want to... And we want to CHOOSE to be horizontal when we want to... And we don't want any BC arguing with us as to what attitude our body is in underwater. In short, that can be accomplised on pretty much all but the crappiest BC's, although I personally have found a few to be the most easily trimmed and neutral when I wanted them to be.

Remember, this may seem like a simple order... But keep in mind something... Your trim changes with a full tank vs. an empty one, since a full tank is heavier than an empty one. So it's not just about achieving the right trim... It's about finding a system that works for you in accordance to the way that your body floats in the water, under a variety of circumstances. Then there's some difference according to the wetsuit or drysuit you wear, whether your diving in fresh or salt water, or how many tanks you dive with. It can get pretty complicated.

That's why everyone seems to be so incredibly passionate about the gear that they dive with.

A word of warning to you on this board... There is a select group of divers here that seem to bash everyone and anyone using anything other than a backplate and wing. Let's just say that it is their opinion that that gear is best, and that they can't see why anyone would ever use anything else. That's like saying that the whole world should only drive Ferraris or that the whole world should only wear "sensible" shoes. Simply put, one specific thing doesn't work well under all circumstances, and they'd be better off learning some tolerance. Be careful of these people, and don't get your feelings hurt from them if you ask questions. They yell at everyone. You wouldn't believe some of the stuff I've seen them say.

Remember, most tropical salt water divers use jacket style BC's. Most "technical" divers such as deep divers or wreck divers use some kind of back inflate BC... And most cave divers use a backplate and wing. Why? Well... Tropical divers like jackets because they generally are easy to doff/don and usually unnecessary to trim. Deep and wreck divers generally use back inflate BC's so they can get the tons of "stuff" they have off of their chests... And cavers generally dive bp/wings because of the bp/wing's indestructable nature, dependable simplicity, and built-in weight of the backplate.

But choosing is more than just looking at what kind of diving you do... It's about what's important to you as a diver, and which of these features interest you most.

Anyway, I personally have found my favorite BC's to be widespread... I really like the Scubapro Classic, which is unusual in that it has no adjustment straps on the chest area. This allows air to flow in and all around the jacket, making for a delightfully trim-neutral BC. I never found this BC to have any problem allowing me to swim in any position that I wanted to... Even if upside down, standing on my head, singing the National Anthem. I also very much liked the sheer quality of the unit, and the terrific hidden breast pockets, big enough for a compass, spare Ikelight, or mini-slate. The one I've used was also equipped with the optional Air II, Scubapro's integrated octopus, which conveniently got rid of one hose while still retaining a high quality secondary air source. Scubapro's integrated weight system I found to be my personal favorite, being the most secure I'd ever used. There's two bad things I can say about the Classic, though... One is the price. At nearly $700 with the optional Air II, I don't think I'll be buying one this year. The second bad thing is that since there are no adjustments on the chest area, fit is very important and not everyone is going to get a good fit from this BC.

My favorite back inflate BC... Well, I'm not really a fan of them, with the exception of one, which you specifically asked me about. Simply put, I've found most back inflate BC's to offer little to trim the rig, and most are in bad need of trimming. Many of them have some kind of integrated weights, most often held somewhere on the diver's body towards the front... While the bladder sits on the back of the diver. This almost always leads to a pretty bad face-forward problem at the surface, and in extreme cases won't let you go horizontal to swim, either. I've also used back inflate BC's who's wings (the bladder) are huge and wildly out of control, sometimes tipping me one way or the other without my intent. There are some exceptions to that rule, though, and one of them is the Dive Rite Transpac II, commonly known as the "Transpac." This unit really is just a backplate and wing, but with a cloth backplate instead of a hard backplate. Most Transpac users do use a crotchstrap, in fact. I found that Dive Rite sold so many accessories that I was able to place the right amount of weight in the right place to achieve correct trim in the water. Like the Scubapro Classic, I found that a balanced Transpac allowed me any body position or attitude I wanted in the water, which to me, is really diver nirvana. The Transpac also has some other advantages which it shares with backplate/wing setups... The Transpac allows the changing of the "wings," meaning that you could select a lot of lift or a little bit of lift. This has advantages based on what kind of water you're diving in, and how much gear you have. Also, most of the Transpac is made of 2" webbing, which is very dependable and easily replaced if anything begins to tear or fray. The biggest disadvantage that I could find with the Transpac, and the reason that I will not buy one, is because of it's compete lack of any hard structure in the unit. I found that this allowed my tank to move around too much on my back (sometimes hitting me in the back of my head, sometimes banging against the backs of my legs) for my liking. Apparently, this isn't everyone's opinion, though, and the soft back of the Transpac has the awesome advantage of being able to fold up into a tiny package for carrying on to planes destined for tropical resorts.

Backplates and wings, commonly known as, "bp/wings," are very interesting... Despite what some people on this board have said, bp/wings are NOT the "newest, latest" thing to hit diving... Rather, they are the OLD BC design, dating back to way before jacket style BC's were invented. They do seem to be making a comeback in some small circles, though, and not without reason. Their simplicity of design and rugged dependability make them very much a favorite with divers who can't simply "call the dive" and surface. I find them a pain in the neck to adjust properly, but once adjusted, don't have to be adjusted again. I find their modular design wonderful for being able to completely customize gear, and trimmed properly, can make the simplest, most intuitive rig around. Under water, they virtually disappear, and many who wear them say that they can't tell whether they are wearing a BC at all. This has obvious advantages, including the rig's ability to "slice" though the water. My personal favorite bp/wing setup thus far is made by Halcyon, arguably the leader in bp/wings. I recently dove with a polished (ooohhh... aaaahhhhh...) stainless steel backplate, which took 6 lbs off of my belt. I wore a Halcyon 27 lb wing, which was large enough to lift me nicely, and small enough to stay out of the way under all circumstances... It also never pushed my face into the water at the surface, because it trimmed nicely (especially since the plate itself accounted for 6 lbs) and because the 27 lb bladder wasn't big enough to push me face-foward in the water. Also, let's face it... Bp/wings are quite macho. :D

Just a quick note on this whole "trim" thing... I know some divers who actually prefer their BC to HAVE a tendency to float them in a certain position... Many cavers are known to prefer a horizontal body position in the water... This often comes from a caver's need to never have their fins touch the ground, which is almost always a very fine silt, which can drop visibility to zero if touched. There are also some reef divers who, never wanting to touch a live coral reef, prefer their rig to naturally float them horizontally. Many times diving instructors will trim their BC's to float them vertically, in a heads-up position so that they can be most able to help their students in most situations. Me? Personally, I prefer a completely neutral setup, as I prefer the ability to place my body in any position I choose... So I can swim upside-down under ledges, sideways into wrecks, stay effortless at the surface, and relax completely while drifting horizontally along a reef. But again, you'll find some people preferring a certain style of trim over another for a variety of reasons.

I'd like to just talk about one more thing, too, that I keep hearing on this board... I keep hearing people talk about "streamlining." It's usually used when someone is talking about the "awesome streamlining" that bp/wings have. Let me just convey my experiences here, relative to "streamlining:" I have swam with some terribly designed BC's... Some which actually blew up like parachutes underwater as soon as I started swimming or experiencing a current. And yes, there's a lot to be said of streamlining. In fact, I would say that to me, it is probably the third most important factor in deciding on which BC to buy... One being, "Will it help me to stay alive underwater," and two being, "Can I balance in the water column with it and obtain neutral trim?" The effects of streamlining are less gear dangling, better visibility, less claustrophobia, less problems in general, reduced air consumption, longer bottom times, and an overall better, more fun and more controlled dive.

I have found that it's not always the case that bp/wings are more streamlined than other BC's, contrary to popular opinion of this board.

I found the Scubapro Classic, with it's vestlike BC, to hug my body nicely throughout all of my maneuvers. I never felt it parachute out underwater, and I maintained position in a current nicely. This is because of the bladder's "all around the body" design. Just to note, the one I dove with had a whopping 65 lbs of lift to it, enough to dive doubles or steel tanks any day, without alteration.

The only rig that I found with better streamlining charactersitics was a Halcyon backplate with a 27 lb wing on it. Simply put, the wing was so small and the straps so smooth and unobtrusive that it just had very little drag in the water. However, this advantage was not there once I added a Halcyon pocket (so that I could carry a few things) and some weights (to trim myself.) And this system only had 27 lbs of lift. I could only dive this rig basically with a 3mm wetsuit and an aluminum single tank. Anything heavier than that and I needed a bigger wing, which very slightly increased my drag in the water, didn't do nice things to my controllability (the rig began to get difficult to trim properly) and lightened my wallet by about $350.

...So to address your question... What is a fredt backplate? Well, FredT is a guy here on the boards (we all think the world of him) that makes backplates. His plates have some unique advantages over some of the other ones out there... For one, he makes plates in a variety of materials, making for the most corrosion-resistant plates in the industry. This also allows him to create plates that have a very specific amount of weight to them. Since most divers need the same amount of weight in all of their dives, they can, with a little experience, select the right weight of backplate, taking a certain, exact amount of weight off of their weight belts. Also, FredT's backplates fit any brand name of gear. Normally, Halcyon's backplates only fit Halcyon's wings... And Dive Rite's backplates only fit Dive Rite's wings... And so on. With a FredT backplate, a diver can mix and match gear nicely and always have stuff that fits together. FredT even takes it one step further by offering different sized plates for different sized bodies. As such, you might hear people talk about the "FredT short, heavy" or the "FredT (regular) light." What's best is that FredT's gear is even more reasonably priced than anyone else's, because he's still just a guy having fun here, not a large company trying to make a killing.

...So what do I pick personally? Well... I got my basic open water certification last May. That's right... The truth is that I'm a newbie, too. :D But since then, I've done over 100 dives, and have earned my Advanced Open Water certification. I've been Rescue Certified and Nitrox Certified, and am taking a cruise this Christmas to dive wrecks in the Bahamas. I've started the USCB Scuba Club ( http://www.USCBscuba.com ) and have worn out four sets of dive gloves. I'm nuts about diving. I've gone over the edge. I've taken a wreck diving class and have done some mild penetration stuff... And have even been PADI Carvern certified... But I'll still be taking a Cave Course at Ginnie sometime mid-winter, and as soon as I can find a DIR course, I'm going to that too, if only to pick up a couple of good ideas from people with lots of overhead experience.

So I'm broke. I haven't been able to buy a BC yet. No kidding. I dive with whatever I can get my hands on, and I spend all my time and money learning the sport.

And I highly recommend it. :D
 
Wht kind of "adjustment" on the water you mentioned that we need to make ???

Also, how would i know how much weight i need ??

My scenario: tropical water diving with swim suit only or the most 3 mm wetsuit or even just a rash guard.

Can u say "OUCH" with the 2" crotch strap with the swim
 
Dxtreme once bubbled...
Wht kind of "adjustment" on the water you mentioned that we need to make ???

"Adjustment..." Well, you shouldn't really need much in the way of adjustments... Once you've got the right fit from your BC. Prior to getting the right fit, though, you're going to be fiddling around quite a bit with the BC to get things perfect. With a bp/wing, adjustments are going to have to be made between dives, with the rig off. With a regular BC, generally you can do all of your adjustments with the BC on, and with you in the water.

Many BC's with adjustable shoulder straps, though, tend to "pull out" when you get out of the water, though... After your dive, the wet rig often weighs enough to pull the wet straps out of adjustment. You won't notice it until you put the BC on for your next dive. I find it kinda annoying personally, but it's no biggie. But just to note... All three of the BC's that I talked about above do NOT have this problem... The Classic doesn't have adjustable shoulder straps, the BP's shoulder straps don't move, and the Transpac has "stays" that keep things tidy. Maybe that's one of the many reasons why those are favorite BC's.


Also, how would i know how much weight i need ??

Take the square root of your foot size and multiply it by the distance between your eyebrows... No, just kidding... :lol:

To find out that information, I recommend doing a bunch of dives. Dive, dive, dive. Spend your BC money on diving and getting more skills. Don't buy a BC yet. Dive, dive, dive. When you have the answer to your weight question, then dive some more and THEN look at a BC.


My scenario: tropical water diving with swim suit only or the most 3 mm wetsuit or even just a rash guard.

Can u say "OUCH" with the 2" crotch strap with the swim

Well, it doesn't bother many people... There's lots of people that are fine with it. I hated it, and was pretty much completely against crotchstraps (I have large thighs from mountain biking) but at someone's recommendation, I tried a 1" crotchstrap instead. The 1" was a completely different story... I could not tell it was there, except that my rig was simply more stable in the water. I'm wearing a 3/2mm suit, by the way.

But that 1" crotch strap for me was fine. The 2" stuck me in the thighs the whole dive and basically ended up pressing on some pretty important body parts. The 1" wasn't that way... No pressure (maybe it was an adjustment issue?) and no more inner thigh pressure.

Having said that, I've found that the ABS plastic hard inner structure of the Classic (which is visible on many high end back inflate BC's) to be even better at preventing "BC creep" (the tendency for the BC to creep up your body and around your shoulders.) Some complain that these put pressure on your torso, keeping you from taking a full breath, and therefore prefer crotch straps. I found no problem with breathing and actually preferred that design to a crotch strap.

Maybe Halcyon could create the "strapless" BP... Forgo the crotch strap for a semi-hard ABS plastic structure that bolts to the backplate and holds on to the underside of a diver's lats instead of through the crotch. I dunno... I'd have to see it in practice to decide if it was better than a crotch strap. The reality is that my first experience was pretty bad with a crotchstrap... But subsequent experiences (with a smaller one) were much better.
 
https://www.shearwater.com/products/teric/

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