doubles in DIR diving wet....

[PerroneFord]

Hmm

When one consults the following chart:

http://www.seapearls.com/tanks-steel.html

You can see that the Worthington LP85 is 6 pounds negative when full, neutral when empty, the same diameter as an AL80, and 1" shorter. It weighs 34 pounds empty.

By contrast, looking at Luxfer AL80s we can see that they are 31.4 pounds empty , 1.1" taller, are -1.4# full in saltwater and 4.4# positive empty in saltwater (or swing from -3 to +3 in freshwater).

This says to me, that the LP85 would take 3 pounds off the belt as a single, or 6 pounds off as a single tank. The tank would not float butt up as it empties, nor does it go positive at the end of a dive. Compound that with the fact that you are getting a true 85cuft of gas at 2600psi, versus 77.4 at 3000psi with the AL80, and this tank starts to look like a real winner, even when diving wet. In a 7mm suit in saltwater, I need about 6 pounds on me. And about 3 pounds in fresh. Since I wear 4# on my AL80s just to keep the tail end pinned down, this is nearly a wash for me.

I don't advocate most steel tanks for diving wet, but I do make an exception in this case.

 

[PerroneFord]

I am not sure the 85's with a wetsuit are a good idea.

Luxfer AL80 is -1.4 full, +4.4 empty
Faber LP85 is -6.7 full 0 empty

I am talking about Worthington steels, not Fabers. I don't recommend Fabers to anyone. Also note that the Worthingon (and apparently the Faber) are listed with their freshwater figures and the AL80 with its saltwater figure. In freshwater the AL80 is about 3# negative. So the net difference to the Faber is 3.7# per tank or 7.4 total pounds with doubles. I dare say that for most divers, unless they are diving doubles in the tropics, they could remove some lead and close the gap of that 7.4# to nearly nothing. I know in my case, I could drop the 4# tailweight so now we're at 3.4# of difference. And I could dump my steel backplate for teh kydex one I want which is about a 3.5 pound differeince. So my net is essentially zero.

 

[Icarusflies]

wow, wow, wow....thank you all for your posts, they are very informative but let me add my comment and forgive me if my lack of diving experience (70 dives) let me say something wrong.

I now dive a steel HP 100 and I can swim it up fine with my wing deflated so I don't anticipate problems with double AL80's.

It looks like the main but not only issue with doubles is the isolator that might be closed when filled. If the blender does a mistake when filling doubles we can assume that he can do the same mistake with single tanks mostly when using exotic gases so besides analizing the tanks and keep an eye on the filling process the problem is the same with single and doubles....right? I always analize my tank at the shop and sometimes again befor the dive so that should cover me.

I understand that doubles are more complex but I beleive that ther offer a degree of safety that ofset the added "danger"....right?

I am all about trainning so what class would you recommend for doubles?....is ther a class for doubles?

Thank you again for all this info, very interesting

 

[aue-mike]

Double Al80s are fine.

Not if you are doing anything deep.

 

[aue-mike]

so unless you need a lot of ditchable weight with the AL80s (unlikely in a 3mm suit), you are (probably) going to be too negative in the steel tanks to swim it up.

wrong.

 

[aue-mike]

I don't recommend Fabers to anyone.

Why? Curious minds and all....

 

[PerroneFord]

Why? Curious minds and all....

After getting in a number of cylinders recently with paint issues (from the factory), seeing those same issues here from members and dealers, and after getting a faber that should have NEVER left the factory (deformed cylinder), I don't recommend them any more. I was never a big fan of painted tanks to begin with, but these quality issues have made me even more leery.

 

[aue-mike]

After getting in a number of cylinders recently with paint issues (from the factory), seeing those same issues here from members and dealers, and after getting a faber that should have NEVER left the factory (deformed cylinder), I don't recommend them any more. I was never a big fan of painted tanks to begin with, but these quality issues have made me even more leery.

Based on the context of your post, I had the impression you were implying some buoyancy-related issue.

 

[PerroneFord]

Based on the context of your post, I had the impression you were implying some buoyancy-related issue.

No, the buoyancy characteristics of the LP fabers seems very similar to the Worthingtons, at least from what I've seen. It's the recent quality control which I am not thrilled about. That and I prefer galvanized tanks over painted. Seems the 19cuft Fabers are very, very popular though.

 

[aue-mike]

No, the buoyancy characteristics of the LP fabers seems very similar to the Worthingtons, at least from what I've seen. It's the recent quality control which I am not thrilled about. That and I prefer galvanized tanks over painted. Seems the 19cuft Fabers are very, very popular though.

no, galvanized are the way to go, but I was following the perceived issues with steel versus aluminum. myopic opinions continue to plague this issue...