JeffG
Contributor
Why? or is it the "purity" factor (dive the rig as it was dove in the past kinda thing)?Walter:
Save yourselves, it's too late for me (help needed)
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Partially, but also because you really don't need one. One of the things I most love about diving vintage is not having all the junk. A mask, a pair of Duck Feet, and a tank strapped to your back with a reg attached - it's a beautiful feeling.
captain
Contributor
Another problem with a tank mounted BC or wing is it will tend to pull the tank and regulator away from your back and the regulator needs to be as close as possible to the lungs.
OP
Hammerhead
Contributor
Right plenty to consider -
The Halcyon Pioneer is a 27lb lift donut wing with 2 cam straps straight through the BP, through the wing slots & around the tank. There is no STA, and also no reason why I need both straps for that matter. Here you go
http://www.halcyon.net/mc/pioneer.shtml
If I remove the upper one and use only the lower, I'm pretty sure it will be mounted low enough without buggering about with the shoulder straps.
Given that my weighting these days consists of 1kg weights (total 2) mounted on the cam strap at either side, I'm not leaning on one side or the other. If I need to pull my legs lower, (I'm already using nice heavy jets BTW), I'll shift the weights to a belt or even 1/2 kg ankle straps, but that might be overkill.
The hose is centralised, I'll have to work with - or around - that.
Walter may be right, I've dived without BCs myself a couple of times (most memorable was a search-and-recovery when I jumped in with a pair of goggles and a tank under my arm to rescue two cases of San Miguel beer lost over the side on a boat trip.
Only problem would be where to get the harness - could use my BP + harness without wing (the BP's ally, not steel), but surely even that would be too negative. Hmm, need to think.
Still need a model number or pic / link of the long yoke Calypso or Conshelf to see if I have something to fit the bill...thanks in advance!
Oh yes, oval masks. Got a couple in fact, my favourite is a Voit from 1961. It's blue and worked a treat freediving just last weekend
The Halcyon Pioneer is a 27lb lift donut wing with 2 cam straps straight through the BP, through the wing slots & around the tank. There is no STA, and also no reason why I need both straps for that matter. Here you go
http://www.halcyon.net/mc/pioneer.shtml
If I remove the upper one and use only the lower, I'm pretty sure it will be mounted low enough without buggering about with the shoulder straps.
Given that my weighting these days consists of 1kg weights (total 2) mounted on the cam strap at either side, I'm not leaning on one side or the other. If I need to pull my legs lower, (I'm already using nice heavy jets BTW), I'll shift the weights to a belt or even 1/2 kg ankle straps, but that might be overkill.
The hose is centralised, I'll have to work with - or around - that.
Walter may be right, I've dived without BCs myself a couple of times (most memorable was a search-and-recovery when I jumped in with a pair of goggles and a tank under my arm to rescue two cases of San Miguel beer lost over the side on a boat trip.
Only problem would be where to get the harness - could use my BP + harness without wing (the BP's ally, not steel), but surely even that would be too negative. Hmm, need to think.
Still need a model number or pic / link of the long yoke Calypso or Conshelf to see if I have something to fit the bill...thanks in advance!
Oh yes, oval masks. Got a couple in fact, my favourite is a Voit from 1961. It's blue and worked a treat freediving just last weekend
Jeff,JeffG:
Actually, you need a better answer for that why than has been given here so far. "BC" stands for "buoyancy compensator." In warm water, with a thin suit (or no thermal protection at all), a buoyance compensator is not needed, as it is used only to compensate for the loss of buoyancy that happens with a wet suit IF you are using standard (71.2, 45, or even AL 80) tanks. We dove without BCs all the time in warm water, and used a surface float (or boat) for when we were on the surface. We also used a snorkel, which a lot of people are getting away from now. In the USAF, as a pararescueman, we never used a BC; we used LPUs (Underarm Life Preservers) for our dives. This type of diving is much "freer" than current diving, as there is no drag from the BC.
BCs are now necessary for high pressure tanks (3500 and above) due to the loss of buoyancy in the tanks (at high pressure). But with a single or twin 71.2 cubic foot tank, that positive buoyance change was not so great that we couldn't compensate simply with our lungs.
Divers now wear a BC with a dry suit, even though the dry suit is buoyancy compensated. Why? Probably the HP tanks which start very heavy, and end up light in the water.
I hope this helps your understanding of the BC. It has become a very expensive dive item, and one that is not necessary for safety in some diving conditions, especially vintage diving in warm water. But it does make the dive companies a lot of money, and provides the safety of buoyance at the surface.
Today's divers are not really as skilled in swimming/snorkeling techniques as divers from the 1960-1980s. Today, it is more commercial, and to make everyone as safe as possible, BCs have become mandated by instructional agencies. This is what we used to call "push-button diving." It works very well for going up and down, but not as well for swimming horizontally, or in current. And, BC design is still evolving. More later...
...Later...Remember what I said above about going up and down? Well, a lot of divers now, with BCs that are supposedly reliable, purposely overweight themselves to enable easy up and down movement. They are 15 to 20 pounds overweighted, and when they release the air from the BCs, they can then "drift" down without effort. They then rely upon their 50-60 pounds of lift BC to move them up too. But for horizontal swimming, you will see that they are not balanced, and do not remain horizontal easily. If they do (and it is possible with properly placed weights and a back BC), they still have a lot of mass to move around. But what can happen, and has happened, is for someone to forget to connect his Low Pressure (LP) hose to the BC, and jump into the water, only to find that (s)he's 15 pounds overweighted, and maybe finless (some people put they fins on in the water) without the regulator in their mouth. I also know of cases where the diver has jumped in overweighted without having his/her air turned on. People have drowned this way, which is why some divers say you need to be able to get to your valves during the dive (high tank mounting).
Vintage divers get around this another way. First, vintage divers are neutral in the water without a BC (if they use a BC, the principal is the same). If the regulator is off, simply switch to the snorkle. If there is something wrong with the scuba, it can be taken off easily, and examined (try that with a winged BC, and overweighted). I hope this has given you some perspective on differing concepts of buoyancy compensation, and vintage diving.
SeaRat
John is right, the BC as used today by modern divers is as a lifejacket to substitute for lack of skill and swimming skill and ease in the water.
However, all that sounds good but most boats including the ones in Florida--especially the ones in Florida--Walter--will not allow you to dive without a BC, octapus, inflator and all sorts of other mostly un-needed junk.
The wing/BP does not pull away from my back, in fact, it stays very close. The wing and back mounted BCs in general work better than a hosecollar but of course they are not vintage--but---these fellows, Purpel and Peter are not strictly diving vintage--they are just using the double hose with a modern rig--which I have done with a BP/wing with excellent results--when set up correctly which I have tried to convery o them.
Also, that Halycon, it has a center inflator hose--that is not going to work all that dandy--sorry--but that is what I bet.
John, a wing/BP can be easily removed and and examined and all that---since it is self contained and has superior balance to any sort of other BC and most especially horsecollar vests. It is a superior system--if you must have a BC.
I might also add a comment on snorkels, I essentially hate them and mostly don't use them. With a single hose, and a BP/wing I just roll over on my back and very comfortably and efficiently-- in rough conditions or smooth--swim on my back. BUT, we have a problem, with a double hose swimming on your back generally results in a freeflow--very annoying---so you must either turn your air off which often I do or use a blasted snorkel. When I use a snorkel I use an old fashioned J tube type, the old ScubaPro shotgun type or even my Nemrod Malaga.
I am often completely amazed how modern trained divers simply have no concept of diving without a BC. The freedom, efficiency, speed, 3 dimensional feeling, comfort is so far superior to diving with a gas bag strapped on it is hardly possible to discuss. It is simply a completely different form of diving that can only be appreciated when you have been trained with the proper types of equipment and skill sets.
N
However, all that sounds good but most boats including the ones in Florida--especially the ones in Florida--Walter--will not allow you to dive without a BC, octapus, inflator and all sorts of other mostly un-needed junk.
The wing/BP does not pull away from my back, in fact, it stays very close. The wing and back mounted BCs in general work better than a hosecollar but of course they are not vintage--but---these fellows, Purpel and Peter are not strictly diving vintage--they are just using the double hose with a modern rig--which I have done with a BP/wing with excellent results--when set up correctly which I have tried to convery o them.
Also, that Halycon, it has a center inflator hose--that is not going to work all that dandy--sorry--but that is what I bet.
John, a wing/BP can be easily removed and and examined and all that---since it is self contained and has superior balance to any sort of other BC and most especially horsecollar vests. It is a superior system--if you must have a BC.
I might also add a comment on snorkels, I essentially hate them and mostly don't use them. With a single hose, and a BP/wing I just roll over on my back and very comfortably and efficiently-- in rough conditions or smooth--swim on my back. BUT, we have a problem, with a double hose swimming on your back generally results in a freeflow--very annoying---so you must either turn your air off which often I do or use a blasted snorkel. When I use a snorkel I use an old fashioned J tube type, the old ScubaPro shotgun type or even my Nemrod Malaga.
I am often completely amazed how modern trained divers simply have no concept of diving without a BC. The freedom, efficiency, speed, 3 dimensional feeling, comfort is so far superior to diving with a gas bag strapped on it is hardly possible to discuss. It is simply a completely different form of diving that can only be appreciated when you have been trained with the proper types of equipment and skill sets.
N
Exactly... I am a new convert to no-BC diving... kinda. I still use my BP/W, but that is usually only when I am using my hp steel tanks and tech dives. Lots more freedom, my dives are now 3 dimensional.Nemrod:
I did have some confusion why people think that you need a BC in cold water. When diving AL80s and LP72s, you only need that weight to offset your wetsuit. I agree with the fact that you would benefit with a BC with heavy steel tanks.
I am in complete agreement with Nemrod about snorkels.
The buoyancy of my 7 + 7 mm (farmer john + jacket) wet suit can change as much as 20 Lbs.fishb0y:
Air weights 0.075 lbs per cu ft (at STP, I like to think ¾ lbs per 10cu ft). Therefore every 80 cu ft you consume your buoyancy change is 6 lbs. This is irrelevant to whether it is a high or low pressure tank. For the buoyancy change it doesn’t matter if the container aluminum, steel, high pressure, or low pressure. All it matters is the amount gas mass being consumed.
thepurplehammerhead
You will be OK with a bp/wing.
A back plate has basically a conventional harness (no silly cummerbund or shoulder straps attached to the bladder, etc.). A harness, back pack, or backplate is IMHO it is the best way to attach your tank to you. You should add a crotch strap and sternum straps (if they are not in place already).
If your harness holds your backpack/ plate tight against your back, having a BC attached to your tank is less of an issue. Just weight yourself properly so there is the minimum amount of air in your BC. In warm water (as mentioned above) there should be no air in your BC. Just because you have it, it doesn’t mean you have to put air in it.
I am using a Genesis, Cayman BC (the least expensive BC I could find) that I have modified the straps to work as a traditional backpack harness and it works great. I used the top of the shoulder straps as it came, but on the bottom the straps now bypass the bladder and attach directly to the backpack. I also use a conventional waist strap and I added a crotch strap.
As I have mentioned in other places, IMHO the best way to use a crotch strap is from the bottom of your backpack to the front of your weight belt. This controls your tank and your weight belt from sliding up. If you want to release your weight belt, it falls free from the crotch strap.
The only objection I have about a back plate is the use of a heavy back plate to remove weight from a weight belt (or the use of weight integrated systems). IMHO it is very unsafe for a diver not to be independently neutral when you remove your tank underwater. If your weights are attached to your tank (and not on you in a weight belt), when you need to take it off (to untangle it, or check it, etc.) you will be up side down hanging on to your rig without being able to use both of your hands to perform the untangling task, etc. This is not as important in warm water with minimal thermal protection and only 2 to 4 lbs of weights.
Have fun with you double hose.
Have it serviced and give it time getting use to it.
Once you get really used to it, you will wonder why did you put up with bubbles on your face for so long?...lol
fishb0y:
Snorkels
During my initial SCUBA training, Harry Hauck (sp?, he was an ex UDT trainer) required us to swim many laps with a tank on our back (full of air, but not using the air), no BC (no one had them), no Maywest, or any other flotation device. First we had mask, fins, and snorkel. Then we left one fin, then both fins. Then we use the fins and the snorkel but no mask. Then the mask, but no snorkel and so on you get the point. Well that was over 35 years ago, but I still remember my thoughts. If I have a long swim and I lost any piece of equipment, I hope it would be my mask and not my snorkel; definitely not the fins (either fin).
Excellent post, John!
True, but some captains, if they know you, will let you dive pure vintage.
True and that's often misunderstood. I think John was addressing a different issue. I know I can compensate for the 6 lb change with my lungs. OTOH, I wouldn't be able to compensate for a much larger change if I were using a larger tank. I believe that's what he was discussing, not the fact it's high pressure, but that some high pressure tanks hold so much more air.
Nemrod:
True, but some captains, if they know you, will let you dive pure vintage.
Luis H:
True and that's often misunderstood. I think John was addressing a different issue. I know I can compensate for the 6 lb change with my lungs. OTOH, I wouldn't be able to compensate for a much larger change if I were using a larger tank. I believe that's what he was discussing, not the fact it's high pressure, but that some high pressure tanks hold so much more air.
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