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

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


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.

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).


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.


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

I kinda had a similar issue.

Use the DR stab plates and then just run the strap through the plate if you want to use your current plate.

The DSS system does not use an STA, and the golem gear stream plate may also be worth looking into as it is different design needing no sta.

I own/used/use DOD, DR and Oxycheq STA's. DOD has been out-of-business for a few years now. my main issue with DOD is the welded bolts, a fixed bolt length became annoying when trying to 'mix' a DOD STA with gear from other companies that are still in business, so now I'm using Oxycheq STA on all my units instead.

You could also buy a drill and put the holes where you like them.

I am aware of many system out there allow single tank diving without STA, but like I said, I chose to use STA for some other reasons, like I want to be able to switch between single and double without redoing can bands, etc. As for thread the band through the plate instead of the STA, this defeat the purpose of STA.

skankpile:

I kinda had a similar issue.

Use the DR stab plates and then just run the strap through the plate if you want to use your current plate.

The DSS system does not use an STA, and the golem gear stream plate may also be worth looking into as it is different design needing no sta.

Click to expand...

I am with you here although I haven't had real issue with the welded bolts yet. Like I said, I think DOD almost had it perfect, if they made it shorter and use standard bolt kits. But I do wonder, why no one makes it right. It is a very simple observation.

scubafanatic:

I own/used/use DOD, DR and Oxycheq STA's. DOD has been out-of-business for a few years now. my main issue with DOD is the welded bolts, a fixed bolt length became annoying when trying to 'mix' a DOD STA with gear from other companies that are still in business, so now I'm using Oxycheq STA on all my units instead.

Click to expand...

GillScales:

You could also buy a drill and put the holes where you like them.

Click to expand...

No you can't. Take the DR sta for example, where will you drill holes to lower the slots to match the plate.

You can probably cut another set of slots, but that is not something everyone can do at home easily.

GillScales:

You could also buy a drill and put the holes where you like them.

Click to expand...

This is what I did with an OMS - drill and an angle grinder - cut two new slots starting an inch below the bottom of the original slot - effectively lower the top tank strap by 3 inches.

UTD's STA has 4 different slots for the cam bands, gives far more options.

eelnoraa:

No you can't. Take the DR sta for example, where will you drill holes to lower the slots to match the plate.

Click to expand...

At least in theory you could elongate the DR slot - I would think it's pretty unlikely that the strap would slide up since that would require the bottom strap to be loose (and even if it was I doubt it would slide). Personally I don't see a need to have the upper slots match - plate to STA - only that the STA slot be equal to or less that the same level as the plate slot.

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