a nutty idea

[jrtonkin]

Just a random idea for someone with a bending brake and a sewing machine to try...

Mill yourself a normal back-plate, but without the channel for the wing-nuts... Just a plate, with a bit of curvature to conform to the shape of your back, and drill holes around the perimeter.

Cut double-vertical-slots in the center about where the normal mounting bolts will go. Thread cam-bands through these slots.

Now take a normal wing of your favorite size, take the bladder out of the outer bag, and sew little tabs with grommets through them to the perimiter of the outer bag.

Re-insert the bladder into the outer bag.

Now tie-wrap all the grommets around the outer edge of the bag to the holes in the perimeter of the plate.

Voila; backplate-type advantages, but without the STA and trough that push a single-tank so far off your back. And with an additional advantage that the bladder won't "taco" around the tank. Of course, tie-wraps aren't exactly removeable, so you lose some reconfigurability, but maybe someone else can come up with a good detachable / reattacheable way to fasten the wing to the plate that doesn't involve bolts or other projections through the plate that could dig into your back.

Not that I've ever tried such a thing (or even a regular BP/wing), it just seemed to be an answer to one of the issues someone raised for using a bp with a single tank.

Jamie

 

[AzAtty]

I believe Halcyon has already done something like this with their new Pioneer series wings. The new Pioneer series has an integrated single tank adapter "welded" into the wing, which eliminates the need for a separate STA and allows the tank to rest much closer to the BP. I think the wing still bolts onto the BP, so it is lacking that feature of your proposed configuration.

The "wingnut channel" on the BP also makes the BP more comfortable than a flat or curved plate, as it prevents your spine from coming into contact with a hard metal plate. If the issue is a bolt protruding into one's back, then it's a simple matter to buy the right size of bolt.

Although I don't want to be one to dampen a creative spark, there is another issue with the proposed configuration. Round tanks tend to wobble a lot when you place them on a rounded surface. A curved BP isn't a stable tank-mounting surface. If you look at a standard STA, you'll notice that it's flat with "ridges" on the sides or a bend or some other method of stabilizing the tank. That prevents the tank from wobbling around once you strap it on. You could put another bend in the BP to make a "tank channel", but if you do that, then you're right back where you started--a BP that will need a "spine channel" to prevent the tank channel from digging into your spine. Having some experience with metalworking (used to work on 200 ton presses at my grandfather's tool and die shop), I think that you'd probably need a heavy press and a die to form that kind of design. I suppose you could cut the BP in half and weld a curved plate into the BP, but I don't know enough about welding to say whether that's even feasible.

 

[O-ring]

I think the wing still bolts onto the BP, so it is lacking that feature of your proposed configuration.

I bolt mine to my bp, but one of my buddies just uses the cam bands to hold the whole thing together. It can work either way..

 

[JamesK]

O-ring once bubbled...

I bolt mine to my bp, but one of my buddies just uses the cam bands to hold the whole thing together. It can work either way..

I am like you buddy. I just use the cam bands.

 

[jrtonkin]

Ahh, the joys of the design process.

Hadn't thought of the problem of tank-slip. I suppose you could build it with two channels, spaced so that a single tank would lie between them. That'd certainly hold it securely in place, though it's getting to be a bit of an extreme solution for as trivial an issue as an inch or two of height. Ahhh, well, such is the road to progress. (I leave it to others to decide whether or not this constitutes progress)

You'd sort of end up with something that looked like:

xxx
xxxxx
_____/\_xxx_/\_____

As for the channel adding comfort, well, a 2-piece 7mm suit provides lots of padding for your spine, I expect

Thanks for the comments, folks.

Jamie

 

[SPEEDSTER]

jrtonkin once bubbled...

As for the channel adding comfort, well, a 2-piece 7mm suit provides lots of padding for your spine, I expect

Not everyone uses a two piece 7 mm suit. And although I applaud your creative ideas, I think you're right, its not worth it for about an inch difference.

M