Kaos
Contributor
From what I've read of your posts, a 27# wing is enough lift for a steel 104 LP tank + SS BP. Is this correct? If not, how much lift do you use?
Single Tank Backplates
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cool_hardware52
Contributor
Kaos:
My wing lift calcs are based on the following assumptions
1. Your diving a wetsuit
2. Your weighted to be neutral at the surface with no air in your wing.
Your wing needs to be able to do two things: The first is float your rig at the surface without you in it. Ditch your rig and it's nice not to have it sink. How negative is your rig? Add it up, i.e. plate tank, reg and misc. Plates are 5-6 lbs neg, you can get tank specs from the manufacturers, but typically your at 20lbs or less, sometimes alot less.
Second thing your wing or buoyancy compensator must due is "compensate" for the only thing that looses buoyancy as you descend, your neoprene wetsuit. How buoyant is your wetsuit? i.e. how much lead do you need to just sink your wetsuit. This may not be equal to your weight belt weight.
Even very large very thick wetsuits seldom require more than 25-30 lbs to sink, most far less.
Your wetsuit will still be somewhat buoyant until you reach ~165 fsw.
If you do the math it's pretty clear that in most cases a 25-30lbs wing is plenty.
When is this no longer true? When you are so weighted or loaded with gear that you can't acheive neutral buoyancy at the surface with no air in the bc.
The real question is what in the heck are 80-90-100 lbs lift wings for?
Regards,
Tobin George
Not the way I'm set up.Kaos:
I have a 4# channel weight held in the bp groove by the cam bands and with that in place the wing won't float the rig with the HID on the waist strap and more than 1000psi in the tank.
However without the 4# channel weight it might have a fighting chance. (seawater of course
)Post Script: I don't think the Halcyon 27# wing has 27# of lift in seawater... at least mine doesn't.
alemaozinho
Contributor
Sorry i can,t see it!!There,s nothing unique about your ss backplates (SS Backplates have been around forever)other that they,re pricier than most of the others,your cam buckles are plastic(or should i say "Space-age Polymer")while many other manufacturers i.e DiveRite have SS buckles,check out the OMS,Oxycheck,DiveRite and Halcyon SS backplates,outstanding quality and guarantees,so what really makes your product better ,other than using a differend CNC-stamp ,Laser and bending machines??The no adapter single tank version slots have been around for a long time too(see Zeagle backplates),for the same price i,ll get the HD 1/4 inch SS Backplate from Oxycheck and if i have a special request about the angle,i,m sure that can be done too!Please convince us in the dive community why we should buy your Products instead.Peacecool_hardware52:
hantzu701
Contributor
If u do a search on ideal wing lift to bp/tanks, you'll find many, many discussions on this. Basically, a larger wing, when empty, will fold up around the tank and add no additional drag. However, the larger wing is increase instability as a shifting air bubble is more noticable. In warm water, I prefer a smaller single wing (<50lbs). In cold water, I prefer a larger single wing.
The integrated STA on a Halcyon Pioneer works as prescribed. I think that the STA is just two rods of delrin in the hub of the wing. If there is any "flop" then check to see if the bands were tightened properly before getting into the water (wet the band, then tighten) and if the harness is fitted properly. Most of the problems that I have seen have to do with ill fitted harnesses.
Since I dive with a single Oxycheq wing, I don't have a choice. I dive with a STA. I like the fact that I can switch out a weighted STA for a regular STA, but you can achieve the same effect with a p-weight.
Think about buying an Aluminum bp. If you are thinking of going to doubles or traveling, you'll want an aluminum bp. You will have to keep more weight on your weight belt, but you'll have more flexibility in the future.
The integrated STA on a Halcyon Pioneer works as prescribed. I think that the STA is just two rods of delrin in the hub of the wing. If there is any "flop" then check to see if the bands were tightened properly before getting into the water (wet the band, then tighten) and if the harness is fitted properly. Most of the problems that I have seen have to do with ill fitted harnesses.
Since I dive with a single Oxycheq wing, I don't have a choice. I dive with a STA. I like the fact that I can switch out a weighted STA for a regular STA, but you can achieve the same effect with a p-weight.
Think about buying an Aluminum bp. If you are thinking of going to doubles or traveling, you'll want an aluminum bp. You will have to keep more weight on your weight belt, but you'll have more flexibility in the future.
Ouch... that is one of the hazards of promoting your product in a thread.
Well Tobin... ball's in your court... play it wisely and with skill.
Well Tobin... ball's in your court... play it wisely and with skill.
cool_hardware52
Contributor
alemaozinho:
Apparently we have failed to communicate what does make our goods unique.
Lets start with Cam Straps and buckles. Yes we do use a plastic buckle, but we also include a compressible pad in the center channel of the BP. The camstrap compressed this pad. This pad does three things, one it maintains tension on the strap as the tank diameter changes, second it limits the maximum load on the buckle, and third it greatly reduces the required closing force. We call these wedge blocks and they can be seen at http://www.deepseasupply.com/page11.html, scroll down a little. Please note we correctly refer to these buckles a "plastic" not space age polymer. We don't use "space age polymer" anywhere. If items are made of a "High Impact Polymer" I will correctly state so.
Note: We actually make this stuff, cut it bend it, sew it, mold it etc. I dislike hype and marketing BS too, if its plastic I say so, if it's elastomeric I say so etc. Unlike many of the companies you reference who are in fact basically marketing companies that really make nothing, we do as much "in house" as we can.
How do I know this? I been a supplier to some of the companies you listed.
Our plates are unique in several ways. The bend is flatter than all I've seen and the center channel is shallower, without loosing the ability to secure doubles. This results in a lower profile when mounting a single. All the loaded webbing slots have overmolded grommets that prevent webbing wear.
These grommets are probably no more effective than a carefully hand deburred plate in preventing webbing wear, but deburring consistently is very difficult and our grommets help to ensure we ship a consistently well finished product.
The use of a dedicated bending die is also part of producing consistent parts. Sure plates can be bent in a press brake, but every batch will vary both in bend location and bend angle as the setup will vary. How much? You might be surprised. You might love or hate our bend, but you can be sure every plate we produce will have the same bend.
I'm not sure why your rant included references to lasers. Makes me wonder if you really looked at our website. We don't have a laser, not yet anyway. It really makes little difference if the plates are cut with a laser, AWJ or punched. it's more about the design and the finish. We do have large powerful Abrasive Waterjet, and that does afford use the opportunity to produce a variety of sheet / plate formed goods.
Your quite correct that "STA-Less" designs have been around a while. It's also quite true that many who have used these previous STA-Less designs are now hard core advocates of STA's.
Could this be because previous STA-Less designs were lacking in some respect? If yes is it AT LEAST possible there is room for improvement?
I will admit that our current website is less than ideal, and it does a poor job of detailing just how the parts of our single tank set work together. I will try to describe it here:
By eliminating the grommets in the center panel of the wing the pivot points that the tank rock on are gone. The wing includes (althought not shown on the website currently) a elastomeric cradle. This cradle is about 3" x 3" and fits between the tank and the BP. It absolutely prevents tank rock and unlike others does not prevent the wing from being rolled up for draining or packing.
One of best parts of single wing however is most apparent only when the dive is over. Our design, i.e. no wing to plate bolts and a single large window in the center of the wing means that one need not unlace the camstraps or even unlace the buckles to seperate the wing from the plate. IMHO it is far easier to flush and clean the wing when it is not attached to the plate. I also prefer to pack and transport my wings apart from my heavier gear.
Our Doubles wing (LCD 50) is unique in that it permits the use of independant twin tanks if desired.
I would be happy to post our warranty statement, have to be tomorrow as I'm home now, you will find it quite in line the norms for this industry.
Pricing: Our prices for complete rigs are very competitive. Individual parts are of course a more expensive route. It's always more expensive to buy a car a fender at a time.
We do need feed back like yours if only to point out where our website needs work.
Regards,
Tobin George
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One question for my own edification, what is the reduction in diameter of an aluminum 80 CF tank fully filled at 3000 psi from surface to 66 FSW?
Kaos
Contributor
cool_hardware52:
I've already done the math and weighed my different components:
104 steel LP = 54 lbs
Plate = 6 lbs
STA = 2 lbs
So when I go out to purchase a wing, I'll need at least 62 lbs of lift to keep it from sinking when taking it off is a must to, per example, get into a zodiac... of course the tank will weigh less than 54 lbs with 500 psi in it. This doesn't give me much choice since most of the manufacturers that I see don't have single tank bladders that offer more than 45#....
Kaos:
You have about the right wing size, but got there the wrong way.
It is the weight of the stuff in the water that counts, not the weight out of the water. Essentially you get credit for the water the stuff displaces and the amount of water a tank displaces is pretty substantial.
PST LP 104 are around -12.5 lbs bouyant when full (not -54) and around -5.0 bouyant when empty. So a pair of them are going to require 25 lbs of lift at the surface when full. The plate and STA are pretty much a wash as they displace relatively little water. So at this point you are at about 33 lbs of lift.
But then you have to consider the weight of your valves/manifold, regs, the weight of other accessories like knives, reels, cannister and backup lights, etc, So 40 lbs of lift is probably a better number and a 45 lb wing would work well.
But then again, just to play devil's advoicate, in rough seas it can be very nice to get your 15 lb head out of the water so a 55-60 lb wing is not really outsized for a set of large doubles on the surface.
With a wet suit, I like to weight myself so that I float at about eye level with full lungs and empty tanks at the surface and sink when I exhale. This leaves you approx neutral at 15 ft with empty tanks and ensures you are not going to be unable to remain at a deco or safety stop.
Under the water, the critical lift issue with a thick (7mm) wet suit is to have enough lift at the bottom to offset the loss of bouyancy of the suit combined with the negative bouyancy of the rest of the rig with full tanks. So at 130 ft or so, you need 40 lbs of lift for the rig and full tanks plus another 15-20 lbs to replace the lift lost to suit compression. So a 60 pound wing again makes sense with a set of relatively heavy steel tanks.
Thinner wet suits have less lift to lose at depth (and a lower weight requirement at the surface) and dry suits use air to maintain volume and essentially lose no lift (as long as they are intact) so a smaller wing can sometimes be used as long as you have enough lift for the worst case condition at both the surface and on the bottom.
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