So I'm curious, I'm not an expert on the backplate wing platform, but I have had my SP Xtek with the 30# wing for a little over a year. What is the deal with Tacoing? I know the sides of my wing will fold up on the AL 80s that I use but I've never had a problem with dumping air. I normally dump air by doing a pike like posture and dumping it from the bottom instead of the power inflator hose.
Decide between wings
- Thread starter Samlazaz
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
So I'm curious, I'm not an expert on the backplate wing platform, but I have had my SP Xtek with the 30# wing for a little over a year. What is the deal with Tacoing? I know the sides of my wing will fold up on the AL 80s that I use but I've never had a problem with dumping air. I normally dump air by doing a pike like posture and dumping it from the bottom instead of the power inflator hose.
ams511
Contributor
In the beginning backplate and wings were for doubles tanks, with the invention of the single tank adapter divers could use a doubles wing when using a single tank. The problem is the center panel of a doubles wing is wide and at the lift of the wing is higher that needed. This is where tacoing got its name because the wing would engulf the tank so much that you wouldn't even see it. The made it really hard to vent because most of the air would be above the inflator elbow and the butt dump.
When using a wing there is a bit of technique involved. You want to make the dump or the hose the highest point so the air flows there. Also when using the butt dump you want to pull the string up to release the air. If you pull down you are lowering the dump and you won't vent properly.
eelnoraa
Contributor
Yes, I have an LCD 30. I thought this looked like tacoing. No?
This is complete normal. The only wing that does NOT do this is Oxycheq MkV. It is the narrowest I have seen, even more so than DSS. But the reason reason is Oxycheq wing outter shell use very stiff material, so still it just can't fold up much. The narrowness futher minimize any fold up. However, wing like that doesn't dive a nice as DSS and Halcyon. You actually want some small amount of fold up so that you can park gas onto one side of the wing even when you roll a little to the other side. But too much fold (referred as taco-ing), you can't move gas around. It is more obvious when you diving double. It is all about the balance.
m0xty
Registered
eelnoraa
Contributor
I don't have a triata wing, but looking at the shape, I do think it should perform as well as Halcyon. However, I do think Halcyon is better in construction, material use and longevity tho. Of course you won't get the same percentage of improvement with same percentage increase in cost. Give a try when budget is allowed (such as in OP's case), I will go for another Eclipse 30
It seems like a donut would stick up around the tank less, no?
Any two wings of the same lift capacity must have the same internal volume, when fully inflated, right?
I don't know what the volume is of a 30 # wing (and I'm too lazy to do the math, just for this discussion), so let's just say it's 30 cubic units.
If a horseshoe wing has 30 units of volume and you compare it to a donut with 30 units of volume, the donut is going to have some volume in the lower portion that passes under the lower part of the tank, right? The remaining volume will be in the parts of the wing that are alongside the tank and around the front of the tank.
So, if the wing has 30 cubic units and, say, 4 units are in the part at the bottom, then the donut will have 26 units of volume distributed through the same area that the horseshoe has 30 units in.
Doesn't that mean that a 30 # donut is very likely to be a bit more streamlined and compact than a 30 # horseshoe? I realize the difference may be very small. But there would still be a difference, right? And it you're comparing a 30# horseshoe to a 25# donut, then the difference could actually start to be noticeable?
To be clear, I'm not asserting that the difference is noticeable. I have only ever dived with my 30# horseshoe. I am ASKING if this is correct and if you can notice a difference (even a small one). Because it seems like a 17% smaller (volume) wing that is also distributed all the way around the tank, instead of just around 3 sides would be noticeable.
halocline
Contributor
It's a valid question, but unfortunately there is no 'standard' way of rating wings for lift. Tobin says that he measures lift by the wing's capacity when its mounted on a tank. This means that any part of the wing that is prevented from inflating due to the tank will not count in the wing's rated lift. Other companies, who knows. A 30lb oxycheq and 30 lb dive rite wing might actually provide completely different amounts of lift. The only easy way to really know is to mount the wing on a tank, fill it with water until the OPV releases, then drain the water from the completely full wing into a bucket and weigh it. Whatever the weight of the water is that drains from the wing is the amount of lift it can provide, because that is the amount of water it displaces.
There's just very little, if any, difference or advantage between properly sized horseshoe or donut style wings, at least for single tank diving. The difference felt diving between wings is usually related to their size, especially width, and their ability to vent easily.
cool_hardware52
Contributor
Close. Both tanks and back plates can constrain a wings ability to fully inflate. DSS singles wings have a 3 inch wide center panel, so they most definitely inflate in the roughly triangular space between backplate and cylinder. Even the overall bend of the back plate can impact the degree of constraint.
To test actual capacity for any given application:
Weigh the wing empty, I prefer to weigh the wing empty while it's laying in a plastic tote bin, i.e. "tare" the scale with the empty wing and tote.
Build up the rig as it will be used. We typically use a large back plate, and 8 inch cylinder. The DSS Large plates are a little wider than a Medium.
With the rig assembled carefully fill the wing completely full of water, I usually lay the gear down so the OPV is the high point. I made up a corrugated hose that has a garden hose fitting and ball valve in place of the inflator, but you can achieve the same result by directing water into the oral inflate mouth piece.
Fill until the OPV vents nothing but water.
Now carefully tear down the rig, and try not to force water out of the OPV. That's what the plastic tote is for, it will capture the water that is inadvertently dumped via the OPV while handling the heavy, water filled wing.
Now weigh the tote and wing a 2nd time. The difference in the two weights is the actual water in the wing. That directly represents the available lift in use with all constraints.
Keep in mind that there will always be slight variations even between two wings of the same make and model. Adding 1/4 to the seam allowance when sewing the shell can cut the volume of a finished wing by ~1.5-2 lbs.
We use the above technique to verify patterns with new designs, but we don't fill every wing made. That's why I would not typically recommend a "26" lbs wing for somebody with a 26lb positive exposure suit.
^^Exactly!
Tobin
Last edited:
Similar threads
