Full face mask buoyancy?

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Doctor Rig

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I just don't log dives
After having an opportunity to try a full face mask for the first time this week, I have a related question. Do full face mask divers find they have to adjust the amount of lead carried and the distribution of needed lead?
 
We use Guardian full-face masks daily here at work. When we are training new divers we recommend that they add about 2 lbs to counter the buoyancy of the mask.
 
Around here no one has added any extra weight when using the Guardian or Neptune. I've never added weights to any of my students learning to use the ffm. I'm not saying it isn't needed. Perhaps some people may need a pound or two.
 
I dove an ocean reef FFM for a year. You can feel the buoyancy on your head a little bit, but it's not something I had to make an adjustment for. I do remember thinking it could have potential become a problem when I first tried the masks in a pool. In the end it was a non-issue.
 
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Minimal.

I did have one PSD diver who really complained (a gov't employee) so I laced 1/2 lb of lead through the top-strap.

(I short poured it into a 1# weight form)

She then went on to have other unrelated complaints, to which I began to offer some hideous solutions. Still laughing, years later. She went on to file a discrimination suit against my replacement. Worked out well.

Dive it before you worry about it.
 
For deeper diving, I rarely added weights to the Poseidon Atmospheres that we use. That said, the accessory weights seemed far more useful in the shallows, say, ten meters and above -- especially with the added buoyancy and bulk of dry suits.

The earlier model weights (left in the photo) were uncomfortably heavy on the mask, after a couple of hours; and weighed in at 800 grams per pair; just short of a kilo. Not so hot. The more recent version -- smaller, more tightly machined, are about 600 grams, which, oddly, makes a bigger difference than I previously would have thought . . .
 

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Just do what they taught us in diving school back in the early 70's. Wear a 36 pound shallow water belt, walk on the bottom.
 
I dive an Ocean Reef ffm most of the time and I've never had to add additional weight to compensate for it. It might make your head feel a bit more "floaty" but not drastically. Certainly not enough to warrant carrying any additional weight. But I also have a QD fitting and a 90 on mine so that could make up for any additional buoyancy. As for distribution, I carry my lead in trim pockets on the upper and lower cam bands around my tank. That gives me up to 20 lbs and then if I need any additional I'll throw it in the ditchable pockets on my BC.
 
As for distribution, I carry my lead in trim pockets on the upper and lower cam bands around my tank. That gives me up to 20 lbs and then if I need any additional I'll throw it in the ditchable pockets on my BC.

Thanks for the suggestion.

I hadn't really considered those trim weights to compensate for the mask's varying buoyancy; and whether or not I was using a hood. A couple of our heavier model BCs have those capabilities. The Atmosphere is a "positive pressure" model (for those unaware of that type of FFM, it slightly free-flows into the mask itself, flushing exhaust; forming a seal; as opposed to those which function simply through "on-demand" breathing, like a conventional regulator) -- also to ensure that the mask remains dry, especially in, uh, questionable water. We noticed a slight difference between two models. One, which was soon due for a rebuild, had released more gas, and was, noticeably, more buoyant than its counterpart . . .
 
https://www.shearwater.com/products/swift/

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