BP/W setup with STA

[DiveDay]

I'm trying to convert a Halcyon Evolve setup to single tank use with a Scubapro STA.

I'm a bit confused on how the STA is supposed to work. The picture below is the Halcyon backplate and harness.

Notice how the harness has a reinforced hole which the top carriage bolt goes through.

However, this means there is substantial extra thickness at the top compared to the bottom, so the STA won't be flush with the backplate. I'm assuming this doesn't matter but I want to confirm that this is normal. Is it?

The 1" carriage bolts that Scubapro includes with the STA are barely long enough to fit at the top due to the extra thickness, but fit ok at the bottom. I can go buy 1.5" bolts, but I want to make sure this makes sense.

Lastly, the Scubapro tank bands themselves have the same type of hole:

These holes line up with the STA/backplate ones, but the carriage bolts are square and cannot pass through them, they have to be installed underneath the tank strap directly into the STA.

So why have these holes in the tank straps at all if they're unusable?

Thanks for your help/advice!

Edit: Page 32 in the Scubapro manual shows them same situation: https://ww2.scubapro.com/media/85806/x-tek_manual_english.pdf

The straps in their manual don't have any grommets at all.

 

[Scuba Cobra]

it will sit on top of the harness.

for your STA, put the bolt UNDER the cam band to reduce bulk. You should find that to fix your thread engagement problem. There is no reason to run the bolt through the cam band as the STA retains it, it will not rotate once a tank is secured in there.

 

[JohnnyC]

The Evolve is a doubles wing. You don't want to use it with a single tank.

Get a single tank wing with slots in the back and you don't need to use an STA, there are slots cut in the backplate for cam bands.

 

[Scuba Cobra]

Disregard.

 

[DiveDay]

The Evolve is a doubles wing. You don't want to use it with a single tank.

Get a single tank wing with slots in the back and you don't need to use an STA, there are slots cut in the backplate for cam bands.

I have a singles wing, it's a Light Monkey 28lb which requires a STA and has no slots for cambands.

 

[divad]

I used to thread cam band like this to protect the pretty white paint on my fabers. The SS Nylox acorn-nut (plus SS lockwasher) was very drysuit-friendly.

 

[DiveDay]

The SS Nylox acorn-nut (plus SS lockwasher)was very drysuit-friendly.

That's a good idea! The backplate I got came with the MC storage pack installed so that protects the user from the wing nuts.

 

[JohnnyC]

Go to the hardware store and buy longer bolts. Then you can rig it however you want.

 

[swimlikethefish]

5/16 x 18 is the standard.

 

[divad]

Go to the hardware store and buy longer bolts.

And maybe a hacksaw.... the Ace Hardware near me has a lot of imperial and metric SS nuts, bolts, lock washers, etc. from tiny to 3/8" . Since it's only a mile away I can go there and tinker 'til I find what I want.