Joining the Dark Side. Do I need an STA (read the other thread, still not sure)

[Web Monkey]

Since my in-laws in FL have kindly offered me some space to keep my gear (ScubaPro Classic+, etc.) for when I visit, I now have an excuse to go buy more stuff, and have decided to try a BP/W.

I'm currently diving single Faber Steel 95's although I may double up at least one set this spring.

I've been looking at Fred Ts backplate (havn't selected a wing yet), have all the drawings and notes (thanks Fred!) but can't seem to figure out if I really need the Single Tank Adapter or not.

I can't imagine he'd make one if it wasn't necessary, although looking at the pictures, I can't imagine that a single tank with 2 ScubaPro straps would be going anywhere.

Earlier (another thread) someone mentioned that "mounting bolts" get in the way of the tank, although I don't exactly see where I'd be using mounting bolts with a single tank.

Can anybody clarify any of this?

Thanks!

Terry

 

[GreenDiverDown]

Sorta depends on what wing you are planning on using. With some wings you can 'get by' without a STA. These wings have 'built-in' STAs usually in the form of rods that are sewn in the center panel on each side of the bolt holes. These rods 'craddle' the cylinder and the cambands lock everything together. Fred's plates have camband slots that match up well with some of the more common wings... in other words... his plates can be used with quite a few wings that don't require an external or separate STA.

 

[FredT]

If diving from a boat, the STA greatly simplifies the tank swap operation, It also makes the tank a part of the plate structurally. The tank will ALWAYS be in line with the plate spine, and you loose the grommet rock and bolt loosening issues of a STAless assembly.

Beach diving where your setup table is the back of your truck where additional tank crutch hardware is available, and you aren't busy just trying to stay on your feet on a moving deck, the STA isn't as important.

 

[halocline]

The problem with the bolts you're referring to is basically this: most wings have a pair of grommets that sit right on the center channel. Bolts go through them to attach the wing to the plate. The tank then ends up resting on the grommets and bolt heads, not on the center channel, which sometimes results in the tank not being very stable. Even if you decide not to bolt the wing to the plate, you still have the grommets. Some single wings don't use grommets (DSS single wings, for example) and consequently you can cinch the tank down on a secure surface. One possibly solution that I never hear people talking about would be to attach rubber pads (that non skid boat decking would be perfect) over the grommet area. On my flat plate I just put a strip of the stuff right down the center, mostly to keep the tank off the back of my head, but it also really improved how tight the tank felt on the rig. The rubber decking I'm using is basically neutrally buoyant and pretty stiff, so it's not like you're putting foam padding on your plate.

 

[GreenDiverDown]

Earlier (another thread) someone mentioned that "mounting bolts" get in the way of the tank, although I don't exactly see where I'd be using mounting bolts with a single tank.

It has become popular to bolt the wing to the plate when not using a separate STA. Cambands thread thru the slots in the center panel and thru the slots in the plate (they have to line up for this to work so you have to be sure that your plate and wing 'get along'.) The bolts keep the rig together as one unit to make things a little easier while setting up and tearing down. The head of the bolt will be behind the wing and behind the ridge of the center channel of the BP. The head of these bolts becomes a high point that may contact the cylinder. If this happens then the BP and wing will not have a solid connection with the curved surface of the cylinder and everything will wobble. You need something that craddles the cylinder to allow a solid connection. That's what an STA does... either a separate STA or one that is built into the wing's center panel... ie those rods that I mentioned. Sometimes those rods won't give enough clearance over the bolt heads and, as such, they won't serve the intended purpose.

In 'the old days' we didn't use the bolts but it was a little tricky holding the plate and wing together while mounting the rig to the cylinder and locking things down with the cambands.

Here you can see how a STA 'cradles' the cylinder...
http://www.ashdesigns.us/stephen/Diving/STA/centerline_1.jpg

 

[ianr33]

Earlier (another thread) someone mentioned that "mounting bolts" get in the way of the tank, although I don't exactly see where I'd be using mounting bolts with a single tank.

Can anybody clarify any of this?

Thanks!

Terry

I use short "mounting bolts" with my singles wing (Halcyon,no STA needed). The head of the bolt sits flush with the grommets on the wing and does not get in the way of the tank. these bolts are not essential but make it easier putting everything together.

The mounting bolts/rods for doubles are MUCH longer and totally different

Jeez you guys are fast !

 

[GreenDiverDown]

As Fred mentioned the STA make things a whole lot easier to assemble. Using an external STA provides for a secure, stable and quick mounting. It also is a slick way to add weight to your rig. I don't leave home without one!

 

[divad]

I used to be against STAs until I was forced to get one (lightweight) for use with a Mach V wing. Now I love STAs. With an upper regular cam band, a lower hinged band, and a lightweight STA I can just throw everything in the general direction of a tank and it magically aligns itself. I still have to close the buckles.

 

[GreenDiverDown]

I still have to close the buckles.

Watch your fingers!

 

[*Floater*]

I used to use an STA-less design, and thought it was pretty cool at the time, but since then I've switched to using an STA. My main reasons for switching were 1) the wing would fall off the plate and hang loosely by the cam straps when there was no tank on top to keep it down, and then I'd have to align it again and remember what position had been good, 2) switching between singles and doubles was a PITA because I had to unthread and rethread the cam straps, and 3) I wanted the STA anyway for rigging independent doubles.

Having said that, diving my rig without the STA was fine too and I could very well see why people would prefer it, especially since the top cam straps slots on some STA's (including mine) are too high for some people (including me). So I'd say start off without the STA, and then add one later if you think you could benefit from it (unless you can get a killer deal on one when ordering with the plate).