Do I have enough buoyancy with this 25lb donut

[Seville]

I put the rig together with a hp steel 120 that was half full. I put it in a trash can and the thing floated, I was able to add about 10 lbs of weight before it became neutral. I just got this donut and thought I would take a chance, it came directly from china via ebay. It does look pretty small on the rig which did concern me. The part that concerns me the most is that the oral inflator hose is more towards the middle of the donut. The opening to where it screws into the donut touches and rubs the tank at an angle. I think this could be a real bad failure point. What do you guys think of this setup? Any other suggestions to get it setup better?

 

[Searcaigh]

Any other suggestions to get it setup better?

Put a regulator on it!

 

[James79]

Looks fine to me, I'd just check on the elbow nut periodically.

Food for thought: you identified 8 lb as the max lead that should be on that rig. You used LB of trim weight with a jacket BC. Your new setup is a 7 lb plate/STA. If I were in your shoes, I'd put 4 lb on the upper cam band, and pool check it with 10 lb on a weight belt wearing your normal gear (7mm wetsuit, everything). My guess is that puts you close (based on your earlier info) and you can fine tune your trim from there.

Respectfully,

James

 

[Scared Silly]

BTW given where you bought your wing it is knock off of Zeagle's

https://www.zeagle.com/product/bcd-components/bladders/30lb-donut-bladder-assembly

Always a bummer seeing knock off crap being bought into the US especially from China.

 

[Jcp2]

I put the rig together with a hp steel 120 that was half full. I put it in a trash can and the thing floated, I was able to add about 10 lbs of weight before it became neutral. I just got this donut and thought I would take a chance, it came directly from china via ebay. It does look pretty small on the rig which did concern me. The part that concerns me the most is that the oral inflator hose is more towards the middle of the donut. The opening to where it screws into the donut touches and rubs the tank at an angle. I think this could be a real bad failure point. What do you guys think of this setup? Any other suggestions to get it setup better?

View attachment 676627 View attachment 676628 View attachment 676629 View attachment 676630

Move tank lower by an inch?

 

[AfterDark]

Move tank lower by an inch?

I was going to mention that. It's the way I position my tank, not for same reason, just prefer it that way, also it puts that regulator where it belongs between my shoulder blades.

 

[Jim Lapenta]

Thanks for the breakdown! I just couldn’t believe how small the donut looked compared to my older BC. I was hoping to have all the weights on my rig so I so not have to have a separate weight belt

Anytime you get more than 10-12 lbs of lead on, you should consider distributing that between several systems so that the loss of any one component does not result in an uncontrolled ascent. There is nothing wrong with a weightbelt being part of that distribution. I normally use a belt for this reason. The belt has individual pockets that allow me, if necessary, to drop 2-4 lbs should I feel it necessary to do that.
A belt goes on under the crotch strap to avoid the risk of accidental loss. However that is further reduced by using a MAKO rubber freediving belt with the pockets I added. Rubber doesn't shift around and the buckle is more secure until you don't want it to be.
Based on your posts, you really should find a good independent instructor who knows what they are doing to put together a workshop tailored to your needs for buoyancy, trim, and gear set up. Not a by the book "specialty class" that won't do much for you.

 

[Seville]

BTW given where you bought your wing it is knock off of Zeagle's

https://www.zeagle.com/product/bcd-components/bladders/30lb-donut-bladder-assembly

Always a bummer seeing knock off crap being bought into the US especially from China.

It does look like the Zeagle is a lot bigger around this backplate. But my backplate was originally with the diverite classic, not sure it it is a little bigger because it was made for twin tanks.

 

[Seville]

Looks fine to me, I'd just check on the elbow nut periodically.

Food for thought: you identified 8 lb as the max lead that should be on that rig. You used LB of trim weight with a jacket BC. Your new setup is a 7 lb plate/STA. If I were in your shoes, I'd put 4 lb on the upper cam band, and pool check it with 10 lb on a weight belt wearing your normal gear (7mm wetsuit, everything). My guess is that puts you close (based on your earlier info) and you can fine tune your trim from there.

Respectfully,

James

Thanks for the calculations! After talking to ppl on here I guess my fear is if I get down to 60-80 feet I wont have enough buoyancy to come up.

 

[lowwall]

Thanks for the calculations! After talking to ppl on here I guess my fear is if I get down to 60-80 feet I wont have enough buoyancy to come up.

A 7mm will always be somewhat buoyant no matter how deep you go. If the rig will float with a full tank without you in it, then it will float with you in it.

The only remaining issue is if the bladder fails, can you ditch enough weight to swim up the rig to where the suit's inherent buoyancy will help out? It won't take that much and you wouldn't want to overdo it since it would lead to an uncontrollable ascent.