Buoyancy: crushed vs new suit?

[northernone]

Picked up a new to me wetsuit yesterday (12 dives on it). 3/2mm men's full suit. Arguable the same size and specs as my year old wetsuit.

Buoyancy check showed I was 3lbs light.

By the end of the dive I needed 4lbs extra compared identical gear and the old suit.

I might test them without me in them some time but fairly confident the ~4lbs is right. I'm surprised a suit loses that much buoyancy (assuming 3/2mm is similar between brands).

Granted, it was used: put it on ~200 times, 46 neoprene cell crushing dives below 250ft plus dozens of hours of tight SM/nomount cave passages and some dry passage slithering. Still didn't look very bad or seem worn out compared to some... Besides for the ventilation stipe in the hindquarters from my Scooter.

Is this sort of buoyancy swing over the life of a wetsuit considered normal?

Anyone else?
Cameron

 

[Billy Northrup]

I'm not familiar with every suit, but some are more "squishy" than others requiring more to sink, require more control at shallow depths and or compress more at depth.

I have a few hundred on my 7 mil and it seems it takes a few less pounds to sink it. Lots of variables.

 

[Rred]

" (assuming 3/2mm is similar between brands)."
You can't make that assumption. Mass market foamed neoprene is made from a chemical batter, very much like pancake batter. It relies on heat and chemicals to make it "rise". So, do you expect that everyone makes the same pancakes? Or bread? No. Same thing with neoprene, the product is all over the place in terms of how big the bubbles are, how much rubber is between the bubbles, how well it holds up or crushes as it ages. Could also be the new suit has more 3mm and less 2mm in it, or vice versa, compared to the old one.
If you want some real fun, take a yardstick or a tape measure and measure off 3 or 5 feet in a straight line. Use a magic marker (inside the suit is fine) and actually mark off five feet. Next year, measure how far apart the two marks are. Pretty much guaranteed it will be at least a half inch shorter, even a full inch by the end of two years.
The only real exception are the nitrogen-blown neoprenes, like the pricey ones from Rubatex.