Bouyancy Without a BCD. PLEASE HELP

[scubakid]

Im humbled here and being new to Vintage diving. Diving without a BCD can be hard work. I have a couple of questions. I would really appreciated some information from you all.

1- Whats the best way to do a Boyancy Check without a BCD? (Even with no weight or Wetsuit with the Tank and regualtor I sink).

2- Do you think the investment of a Horse Collar BCD is a good one?

3- Do all of the Horse Collar BCD have independant Air inflation systems?

4- How do you convert the Hooka Port on at 1971 Aqualung Royal Aquamaster so that it will either an attachment?

5- The Hooka port is low pressure? Is there a way of adding at pressure guage to the Hooka port?

Thanks.

[Tom]

What type and size tank are you using? The old steel 72 has the best bouyancy. I am 5'11" 150#'s and with a 72 and regulator I am about neutral in fresh water. Do you sink even with the tank empty? At times I use a horse collar with oral inflation only. The hooka port is low pressure so there is no use for a gauge. New banjo fittings are available from Broxton Chuck here on the board. Bryan at vintagedoublehose.com has adapters for hooka ports for BC inflators.

Tom

[John]

1. get in the water (salt or fresh depending where you are going to dive) with your tank at about 500 psi and see if you sink or float.

2. My opinion if you are diving without a wet suit and you are negative already you need a BC/vest. Remember, the AtPac came out in '71/'72 so a horse collar is not your only vintage choice.

3 no, but those of us who got certified long ago, we were taught without the aid of a power inflator, take a breath-reg out of mouth-blow into vest-reg in mouth-take a breath

4 and 5 have been answered.

[swimjim]

Pardon my ignorance, but what is an Atpac?

Thanks

Jim

[Deleted]

If I remember correctly, an Atpac is a hard plastic shell bc combo that fit around your tank on your back and had, what is now called a back bc, inside. Not sure why the hard shell was developed, guess the engineers figure most divers would catch the soft bladder on something like a "manhole cover" while pretending or actually swiming thur sewers like Loyd Bridges did in one of his episodes to rescue son Beau who was in that bit.

Anyway, later back bc's, or wings some like to call them, were sold without the plastic shell.

I liked them when I was younger cause I could show off my hairy chest while diving......aka mike nelson. ie: nothing covering my body save for the tank straps.

Now my scarred belly gets the attention.

Texas

[Bryan]

AtPac was one of the very best BC's ever designed. It was made by Seapro/Watergill/AtPac in Fountain Valley CA. It was a pac/wing/integrated weight design 20 years before the current craze. In the later years of it's production it had a very streamlined retractable/expandable bladder system. It had a few flaws but I dove them in all versions and they were fantastic.
The Seapro company produced many other products that were years ahead of their time.

I believe several of the list members still have AtPac's and use them. Perhaps they can post some pictures.

[Deleted]

Ok Bryan

I bow to your better knowledge,,,,,,,,who made the hard plastic shell version with the internal bladder?

Texas

[Bryan]

You are right !! In the early days the AtPac came with a hard shell exterior. They were laced to the pac and were a real pain to fill cylinders when they were on. At that time the bladder looked more like the wing type back bc and was protected by the shell. In later years they were made from lycra curved around closely to the pack.

[Deleted]

Thanks

I'm glad to know my deteriorating memory isn't as bad as I was thinking. Didn't Scubapro sell something similar?

[YankDownUnder]

ScubaKid,

There are several solutions to your problems, as I see it:

1. Dive a wet suit, even if the water is warm where you are diving. A 3mm suit can be used in most warm waters. I lived in Hawaii for three years and needed a suit even there. You could find a custom suit maker and have one made in the vintage style. My first suit was a Pirelli and it had smooth black neoprene on the out side and yellow seam tape. That was 1960. I have just been measured for a replica of that suit. With a suit, trim your lead so you just float with a tank at 500 psi. A full tank will take you down and when you need the lift after the tank empties. you will have it. You won't get the lift on the bottom, but as you swim up the compressed neoprene will expand. Always carry a snorkel attached to your mask. With a snorkel you can watch obtacles below, and get enough lift as more of you is submerged. Some vintage suits are available on Ebay too. Make sure you can dump your lead if you need to do so. One finger release, wire belt buckes are great. They are still available at your dive shop. Have them check the accessories catalog as they won't know until they seach.

2. Many early divers used a military Mae West with oral inflators and CO2 cartriges. The oral inflator was used to trim the diver if needed, but there is no blow off and you can rupture the Mae West as you surface if you fail to release the expanding air. The CO2 filler is worthless except for it's surface roll. Those can be found on Ebay if you continue to watch. I don't like them myself. US Divers made a horse collar (yellow, black and blue) with a LP hose inflator and they are also seen on Ebay. Nemrod and Fenzy made horse collars with small tanks attached, that could be scuba tank filled. Have the cylinder VIPed if it cannot be tested. No sense in getting a shrapnel tattoo. They were steel tanks, and steel rusts. Don't trust the external appearance, that means nothing. I have seen several of these on Ebay recently. They will re-appear if you keep watching. Don't be ashamed of using a horse collar if you feel you need it. Check Dan's site. He may have one.

3. Get a banjo fitting to go between the tank and the regulator for a gauge, I love mine. There are two treads for pressure gauges, the banjo fits one, but it is the more common one and adapters are available. I had to get one. You will need a regulator with a long yoke. The later USD ones which are bright chromed, will usually work, or you can re-fit a long yoke from an early single hose USD regulator. I understand the Voit Triest has both high and low pressure ports and there is on on Ebay now. I have never owned one so I am not sure about this.

4. The USD hookah is a LP take-off. LP in or out. Attapters are available, but you will need a slightly longer hose as they come off of the right and the BCDs fill on the left. A swivel would help here, and dive shops have them. Check the O rings on the adapter, mine leaked slightly.

Above all, be safe and don't take chances.

Good Luck,

[SeaRat]

Scubakid,

There is another way to deal with your heavy tank. You could put enough floatation on it to counteract the tank's negative buoyancy. You would want it to be neutral at about 500 psi to work well, which means it would be somewhat heavier at the beginning of the dive. Cousteau did this for his dives on the Brittanica, where his divers were wearing heavy tripple tank units. If you look at the photos of those divers, you will see 6 round floats on each unit.

Buoyancy control was always a problem for vintage divers with wet suits. We started with the Mae West we got from surplus stares, but it did not work well as it was not made for immersion in salt water (it rusted). The horsecollar BC was then used for quite some time. AtPac and other tank-mounted systems are not too good with double hose regulators, as they tend to raise the regulator off the diver's back and make them harder to breath.

One really innovative BC was developed by Bill Herter in Newport, Oregon (owner of Deep Sea Bill's at South Shore). He manufactured custom wet suits, and he built a bladder into the back of the wet suit by sandwitching two layers of 1/8 inch neoprene (sealing them with seam take in the inside). He had an inflator hose coming from the back between the shoulder blades, and it hooked into your regulator inflator hose. It was one of the first "push-button diving" BCs developed, in about 1972.

John

[John]

FYI, I still dive my atpac retractable bladder, but a couple of years ago I switched over to a SS backplate. I went from a horse collar to a ScubaPro back bc and then in '78 bought my atpac and loved it. When I was diving it skin diver was still claiming them dangerous!

[SeaHunter]

SeaRat,
What WERE these 'floats' that Cousteau used? What were they made of and how did they attach them?

Also I'm curious about the safety of the diver hence they surface and are tired or have to deal with currents, etc.

[Captain]

Here is my method for bouyancy control when diving with a wet suit and no BC. Remember Boyle's law. as pressure increases volumn decreases. The biggest volumn decrease is in the first 34 fsw where the suit compresses to 1/2 its surface bouyancy. If the suits surface bouyancy is +10 # it would be + 5 # at 34 fsw. If the dive is to 34 fsw or deeper I try to be suit neutral at 34 feet. This means you would use what ever weight you would need without a suit plus the weight needed to get the suit bouyancy neutral at 34 feet. An easy way to figure out suit bouyancy is to put the suit in a mesh bag and add weight until it floats just at the surface. Whatever the amount of the weight is add 1/2 of it to what ever weight you need with no suit . You would need to go to 99 fsw to again lose 1/2 of the bouyancy at 34 fsw which would be -2.5 # at 99 fsw if you were suit neutral at 34 feet. You may have to kick or pull your way down to 34 feet but once there and deeper breathing and lung volumn start being effective for bouyancy control. Of course the thickness of the suit will also have an effect and it is best to use as thin a suit as possible for the temperature conditions.