Gettiing to 32%

[Dive-aholic]

I rarely get more than .5% variance from my target fill doing my own EANx PP fills. I do fill slowly, but not 12hrs slow. I do purge the valves for a second or two before analyzing, as I believe that the "last gas in" will collect in the valves/manifold. Maybe that helps?

Same here. Usually I'm right on with the mix I'm looking for.

 

[Superlyte27]

Within 5 minutes of filling?

 

[Dive-aholic]

Who said anything about within 5 minutes of filling? I've already stated previously in this thread that the shop should be doing the fills long before the morning the tank is being picked up.

 

[Superlyte27]

The guy previous to my question. He said he was getting .5% immediately after filling. Which is why I stated I thought he was filling from a bank and not PP blending. In literally 1000 fills, that's so rare for me I can't even remember the last time it happened.

---------- Post added December 1st, 2013 at 11:52 PM ----------

Ditto....I dive 32% regularly and analyze the tanks right after they're filled.......1/2% variation from 32% no problem, any more I'd be suspicious........a 1 to 2% variation will effect your MOD and Deco time......Especially on multiple dives.......

Pretty stinkin rare for me.

 

[RJP]

Who said anything about within 5 minutes of filling? I've already stated previously in this thread that the shop should be doing the fills long before the morning the tank is being picked up.

From the time I close the valves until I take tanks out of the water bath (lifted straight out with a winch) get out the analyzer, nitrox binder, duct tape, and sharpie.

What pressure are you filling to, and how fast? Are you going from dead empty?

My typical fill is a set of double 119's starting with ~700psi of something between 28-36 and going to 3600psi of same. Looking at log sheet my last fill was to 35.4 when I was shooting for 36... so technically I guess I was off by more than .5%.

 

[Dive-aholic]

I'm topping off tanks. I usually boost in the O2 then top off with air. With that I can get my mixes pretty close, usually right on within .1-.2%. Trimix is a different matter. I boost in the helium and O2, let the tanks cool, reanalyze to make sure I'm still good and then top off with air. Occasionally I have to boost in a little more helium or O2. I'm filling to 3600 psi, starting around 1500-1800 psi, and doing slow fills. I fill slow enough that the tank temps only rise a few degrees.

 

[AfterDark]

Tell your shop that mixing it 10 minutes before you pick it up is no longer acceptable and that you'll reject any tank that doesn't analyze right before you leave the shop.

bingo!