STA design - unreasonable, intentional or just no one thinks about it

[halocline]

They should just have slots run the entire length of the STA so you can put the bands wherever you want. It would not be that difficult.

 

[Aqua-Andy]

They should just have slots run the entire length of the STA so you can put the bands wherever you want. It would not be that difficult.

Sounds good in theory but then the straps would slip to the bottom of the STA and would be a pain to attach the tank.

 

[scubafanatic]

I know we can do all the alternation, but why no manufactures notice the unreasonable design here is my question

Well, don't be too hard on scuba gear manufacturers, we've only been able to scuba for the last 50 - 60 yrs or so, moreover, an STA represents pretty advanced technology (involving 'stealth' coatings and dilithium crystals) so it's unreasonable to expect them to have perfected such an exotic concept with only a half century of experience.

 

[mahjong]

The STA's that best address this problem offer 3 sets of cam slots. The shortest one overall that I have found that also has 3 sets of cam slots is the Agir-Brokk (see pic). This STA is 11 13/16" long. As you can see, those cam slots allow for very close cam band placement, so you can mount your tank any way you wish.

I use the Oxycheq weighted STA, which is longer overall (13") but still provides 3 sets of cam slots, so tank height adjustment is no problem.

 

[halocline]

Sounds good in theory but then the straps would slip to the bottom of the STA and would be a pain to attach the tank.

Sorry, i didn't mean one long slot, I meant a series of slots right next to each other.

 

[buddhasummer]

For reason that is outside of the topic here, I am a STA user. I have had used STA from 3 manufactures: DiveRite, Deep Outdoor, Halcyon. I haven't been 100% satisfied with any of these. The main issue is the relative postion of the cam slot on the STA with respect to the bolt holes, specifically the top bolt hose, and also with respect the the cam slots on the backplate.

First, Deepoutdoor vs Halcyon. Also the DR for reference
View attachment 126535

Left is DOD, right is H. Notice the slot is higher on the H by about half of the width of the band, so about 1 inch.
View attachment 126529
DR version. If you pay attention to the bolt location vs the cam slot location, the cam band will be another 1 inches higher than the H.

Now, STA mounted on backplate (H standard size).
View attachment 126533View attachment 126532

DOD STA on plate plate. Left picture is the top, righ is the bottom. Notice the band on the STA is still higher than the slots on the plate, by half inch. DOD STA maintain the 11 inches separation between top and bottom slots, makes the STA very long. As you can see, the bottom extended belong the bottom of the plate.

H STA on H plate. You get the idea. You can imagine the DR STA will make the camband even higher.
View attachment 126534

Most STA out there are cut like DR's. The issue is this kind of STA makes the tank sit ~2.5 inches higher than without one. For smaller divers, this is way too high. It means head hitting first stage. Very uncomfirtable dive. Halcyon and Hollis or similar cut are better by 0.5 inch. But DOD one are 2 inches lower. It is the best in this aspect. The only issue with DOD are it is a bit long.

I think manufactures should really think about this. I think the ideal STA would have the top slot under to match the slot on the plate, but the bottom slot line up with the bottom bolt hole. So it will allow divers to mount their tank NOT any higher than without STA.

I think DOD almost had it perfect except when diving with short tanks like HP80. H is also close, but I wish they can shift the slots to one side by 1.5 inches.

Just random vent on Sunday morning

Totally agree, I have used DR, Halcyon and Hollis STAs. I ended up cutting two more slots in my DR plate (Nemrod mod) I now use AGIR STAs which have two pairs of slots in the top which has solved my tank positioning issues. They were not cheap but fit my needs so worth it to me.

**sorry, late to the party just realized someone else has already mentioned AGIR STAs. (post#14)

 

[WeldonDowd]

Cut the sta in half and put the two parts anywhere you want. Might have to shorten each one a little as well. I use to use a hammerhead plate that came with a two piece sta that could be put anywhere you wanted, after you drilled holes in your plate of course, which is no big deal. Modifications are sometimes the only solution.

 

[Peter_C]

I know we can do all the alternation, but why no manufactures notice the unreasonable design here is my question

No need to alter anything, just make it from scrap! Then you can set it up anyway you want.

I have something like an STA on one of my plates, that has lead poured in it. Total cost was around $4.00, and I had some leftovers that got re-purposed.

 

[eelnoraa]

Peter, can you show some pictures? I would like to make one

 

[Peter_C]

Peter, can you show some pictures? I would like to make one

Do you have the equipment for fabrication? Most anything can be made with a saw, a drill, a few files, and some simple hand tools, but I must admit a plasma cutter, couple of grinders, and a belt sander do make it much easier.

Photos from this thread, although you might not be able to see it without opting in.
http://www.scubaboard.com/forums/solo-divers/370472-fish.html