Questions about twinsets.

[KenGordon]

I saw the pictures and that is exactly what he had. So I assume you just attach the twin bands to a single-tank backplate and presto.

Note always. Imagine having two bands next to one another. They both have to pass through the (plastic) backplate twice to form a figure 8. That means at least three slots in the backplate. Mostly they only have two slots, maybe two sets but one set above the other not side by side.

This is hard to get over without a picture. You can sort of see in the third picture, from the rear, here AP COMMANDO | AP Diving

 

[UCFKnightDiver]

Recreational BCDs don't usually have the rigidity necessary to carry the weight of heavy steel doubles on land, the lift capacity to lift heavy steel doubles in the water, the stability (roll left and right) in the water, or a way to mount the doubles securely to the bcd. I wouldn't recommend trying to dive doubles with a recreational BCD

 

[Scuba_Nick27]

Note always. Imagine having two bands next to one another. They both have to pass through the (plastic) backplate twice to form a figure 8. That means at least three slots in the backplate. Mostly they only have two slots, maybe two sets but one set above the other not side by side.

This is hard to get over without a picture. You can sort of see in the third picture, from the rear, here AP COMMANDO | AP Diving

Oh yeah. I get it now. I just checked my BCD, and the backplate has two slots. So that would accomodate two double cam bands... Thanks for the link, I will save it.

 

[Scuba_Nick27]

Recreational BCDs don't usually have the rigidity necessary to carry the weight of heavy steel doubles on land, the lift capacity to lift heavy steel doubles, the stability (roll left and right) in the water, or a way to mount the doubles securely to the bcd. I wouldn't recommend trying to dive doubles with a recreational BCD

Would a Mares Pure SLS count as a recreational? It is a wing BCD and people say it's more of a mid-higher level bcd.

 

[KenGordon]

Really he means “feeble plastic BCDs”

There is no particular issue in the water, but moving them about on land you need to take more care. It is 35kg of steal strapped to something made of plastic.

 

[greeniguana]

Even if you could figure out a way to mount 2 tanks to a BC like that one, I'd be very concerned about the plastic fasteners holding the extra weight.

 

[grantctobin]

Would a Mares Pure SLS count as a recreational? It is a wing BCD and people say it's more of a mid-higher level bcd.

Yes, it is a recreational BC. No, please don't attempt to dive it with doubles/twins.

 

[Scuba_Nick27]

Yes, it is a recreational BC. No, please don't attempt to dive it with doubles/twins.

Haha alright gotcha

 

[KenGordon]

Even if you could figure out a way to mount 2 tanks to a BC like that one, I'd be very concerned about the plastic fasteners holding the extra weight.

Which plastic fasteners? The cylinders are each held on by a strap, as with a single cylinder. The strap goes through a slot, as before. It can’t be weak at the extra slot, but if it has three or four slots they ought to built for this. The shoulder straps need to be appropriately attached, but again if they put in the extra slots they should be. Are you worried a single 18l will break those? Compare two 12l cylinders with an 18l and a load of integrated weight.

All the buddy BCDs support this and a few others. It is not the most common feature but not totally unusual either.

 

[greeniguana]

Which plastic fasteners? The cylinders are each held on by a strap, as with a single cylinder. The strap goes through a slot, as before. It can’t be weak at the extra slot, but if it has three or four slots they ought to built for this. The shoulder straps need to bet appropriately attached, but again if they put in the extra slots they should be. Are you worried a single 18l will break those?

Whatever this is, it doesn't look like it's up to the task.