Tank Score! Some questions..

[Slüdge]

or somehow end up more negative than 104s

If they're what I think they are, count on it.

[Greenwood_60]

If they're what I think they are, count on it.

Including gas? Huron Scuba lists a "PST MP 72" at -6 empty and -11.4 full, and a PST 104 at -3.3 and -11.27, respectively. A 104 with a cave fill should be around -14. A tank the size of a 72 that is 14 lbs negative sounds more like a boat anchor. As a total WAG, noticing most PST tanks are of similar buoyancy empty, if the MP 100 is -6 empty, it should be -13.5 full. I am OK with that... but it's pretty borderline. I will dive them this weekend and let you know.

[Greenwood_60]

If they're what I think they are, count on it.

Those are some negative tanks! I got the feeling they were every bit as negative as the 104s... but MAN were they a pleasure to dive with. Had no idea how much tank I was really dealing with, with the 104s. Did 2 dives in Madison over the weekend, first with the 104s and then with the 100s. Both dives were absolutely enjoyable (thanks Louis and Rhett!), but the 100s we refreshingly small and low mass. The best part was they trimmed out almost identically to my 104s. If your customers are interested, the 3180+ Faber 100s seem to be in the same ballpark (buoyancy wise), although I would expect trim to be a bit different.

[dnscarboro]

Please make sure when you get them hydroed they know how to do it properly...if you take them to a fire ext hydro they will never pass...fyi These are great tanks and should have no issue will hydro unless they have been mistreated (badly) lord know us cave divers never mistreat a tank!!!!

[Greenwood_60]

FW came across this information and forwarded it to me:

Type psi lgth dia wt in air buoyancy empty
Steel 94 Short 3000 27.6 7.1 39.2 -7.7
Steel 104 2400 29.4 8.0 44.5 -2.8

The discrepancy in negative buoyancy is not so bad when full... but it's still pretty negative. It ends up making buoyancy much more work. I'm back on the fence about keeping them again.

dnscarboro: These actually have a 2011 hydro, so I'm good for a few more years. My hydro shop is Pasco Fire and Safety, and they do an excellent job with steel tanks. The owner is a diver, and generally considers something went wrong with the test if a steel tank fails (some notable exceptions notwithstanding).

[Slüdge]

I'm back on the fence about keeping them again.

If you decide you don't need them, PM me your phone number and I'll get it to that couple.