Which brand of steel cylinder / tank should I buy?

[Rick Murchison]

I own both OMS and Pressed Steel tanks. My OMS valves are on a couple of Aluminum 80's 'cause I don't like 'em but I'm too cheap to throw 'em out.

I have my OMS 85's doubled with the Scubapro isolation manifold, whose valves I find much smoother and easier than OMS's. The OMS 85's are, in my opinion, the "sweetest" doubles I've ever used - lighter but still with excellent buoyancy characteristics.

The Pressed Steel 95's (that used to be my doubles before I got the OMS's) are rigged with "H" valves (Scubapro) and are used in environments where doubles aren't needed but full redundancy still is.

The principle difference in the Pressed Steel and OMS tanks is weight - for any given size, OMS are considerably lighter, yet maintain excellent buoyancy characteristics. OMS tanks are also more expensive.

As for composite tanks, their buoyancy characteristics are terrible - they float like corks.


Rick

 

[Iguana Don]

Sorry I didn't make it back here last night, came home today and my ears started to burn.

One other thing Dee forgot to mention on pond diving, if the heard has left and you dive, and the water has a yellowish tint to it, don't surface! Also forgot to mention, DO NOT rinse your mouth out with pond water, especially water that has the yellow tint to it.

How about the "Platex Divers"

Back to the PS vs OMS thing, How do you get through the PS website.
http://www.pressedsteel.com

Can't get specifics on the tanks.

 

[rainreg]

Sorry about not getting back to you on your questions, its DEMA crunch time and all of my time has been devoted to DETA and DEMA, I will respond after I complete these last few projects for DETA.

Take care and well, keep up the good work guys, there is alot to say about this subject.

When I get back online to reply, Bring your pencils...

rainreg

 

[devjr]

The process used to "galvanize" tanks does not involve electrolysis. The bare tanks are screwed into a jig or framework beneath a hydraulic ram and plunged into a vat of molten zinc. The galvanized finish will last for years if properly cared for. Basically, wash with fresh water after use. After 10-20 years, some rust may bleed through the zinc. If the owner wants to keep the tank it is possible to refresh the galvanized finish through a process called "flame spraying". The tank is sandblasted and chemically cleaned. A high temperature plasma gun is used to spray liquid metal onto the tank. This will not harm the tank in any way and will last for about 10 years. The finish can not be rubbed off by tumbling, etc.

 

[100days-a-year]

Along the OMS vein. Who makes them for OMS?Does this company sell the same tanks significantly lower than an OMS dealer can?Hint check dimensions for tanks and rated capacity.Proper tank maintainance makes tank composition a moot point.excepting the fact that zinc dust is carcinogenic. They are similarly affected by electrodeposition at the valve.Transfer +to- or -to+ still = stuck valve.

 

[Rick Murchison]

Faber

 

[devjr]

OMS tanks are manufactured by Faber, Italy. They make a "low" pressure tank rated at 2400+ and a high pressure tank
rated at 3180+. These tanks are very strong and some divers overpressurize them on a regular basis. (I take no position on this either way). The quality of these tanks is evident by the exterior and interior coatings. The exterior galvo and paint are heavy duty. Inside, the walls are coated with a non toxic oxide which inhibits rust. Interestingly, the high pressure tank can be legally filled to 3498 psi which is just under the industry dictated standard for DIN valves. As a result, the high pressure tank has a standard 3/4 inch neck which allows yoke type valves as well as DIN. Also, and this should be noted, the high pressure Faber tank has thicker walls and weighs more than the PST hp tank. As a result, the Faber hp tank is about 13 pounds negative in salt water which must be compensated for by the diver by adjusting lead or air ballast.

 

[devjr]

The oxides formed on zinc galvo are of no health concern to divers. Zinc oxide is commonly used in medicinal preparations such as "calamine lotion" and is recognized to benefit human health in small amounts.

 

[Aegir]

Hi there

Shortly i will be getting my own 15 litre steel tank and a 3 litre Pony bottle. Could the people of the board give me some ideas as to what brands are the best and what there buoancy characteristics are also. Are there any special conciderations as to a pony bottle (steel or Al)?

For example, i have heard that faber and Tor-Tec have very different buoancy charateristics.

 

[Green_Manelishi]

in reality there are very few tank manufacturers. the major
brands buy the tank, place their logo on same and sell it
for "a few" (ha) dollars more.

i would caution against STEEL as a pony.

http://www.diverlink.com/gear/tanks.htm (i think) shows some
characteristics however I do not gaurantee the accuracy
of the data.