What size cylinders are in use for argon/air drysuit inflation?

[Jimmer]

I'm planning on taking NAUI Tech1, and because of the use of Heliotrox for the class, we need some sort of alternate drysuit inflation. The instructor tells me a lot of his students use their sling bottle for their DS, but I personally like the idea of being able to remove my sling bottle for whatever reason that may be. So what is the general consensus out there? I've considered LPsteel 13's from Faber, AL14 2015 PSI luxfers, and just a regular AL 13 3000 PSI bottle. Pros/Cons alternate ideas?

Thanks,
Jim

 

[JeffG]

Sling bottle for their drysuit????

Anyways, 6 ft3 AL.

 

[Jimmer]

Sling bottle for their drysuit????

Anyways, 6 ft3 AL.

Yeah, I don't like it at all. The instructor didn't recommend it, just that some have done that. I heard one rather funny story of a student who opted to use his O2, while he had warming patches on his kidney's that activate when exposed to O2. Apparently he couldn't get his DS off fast enough when they got in the boat.

 

[Doc Intrepid]

GUE standard is either a 6 or an LP 14, Luxfer, no steel, and no metal to metal connections.

If you're going INSIDE something, put a 6 on your plate. You'll never know its there.

But, you'll need two of them for a weekend, they both need annual VIPs or some shops won't fill them, and they are twice as expensive to buy, fill, etc.

Alternately, many guys use Luxfer LP 14s if they are not necessarily penetrating confined spaces. Benefits are that they allow you to pull off 5 or 6 dives over an entire weekend without needing a refill. Instead of paying two fill fees, you only pay to fill one tank. Instead of two annual VIPs you pay one. Much cheaper to operate over time.

Downside is that they are bulkier. Although, George uses them in larger caves for longer pushes, and has written about doing so. He attaches them to the doubles with velcro bands (see below), so if he hits something with the tank while scootering it just shoves the tank downward in the bands and tends not to damage things. Here is a photo of the bands for both 6's and 14's (I own and use both - they work great for me, YMMV):
Halcyon: Drysuit Accessories

If you use a alum 13, rated to 3000, T's of Argon seldom come at pressures above 2200psi. No one boosts Argon. So, you'll never get a full 13. This is why an LP 14 - which only fills to 2015psi - makes more sense as an argon tank - and you'll get full fills for it.

FWIW.... YMMV.

 

[limeyx]

Sling bottle for their drysuit????

Anyways, 6 ft3 AL.

Yeah, a 6cft works perfectly. I can easily get 5-6 recreational dives on one bottle.

Also you can get a cheap "argon reg" and OPV (I got mine from Salvo for about $70) if you dont want to put a full 1st stage on there.

 

[do it easy]

I use an AL14 mounted to the backplate- it is a bit bigger than the AL6, but once I hit the water, I hardly notice it. I mount it using a loop of scientifically designed bungee around the tail of the tank and a smaller loop of non-bungee line to trap the neck. It can slide up and down and there is some play in the tail, but it's not slack because of the bungee.

The advantage is that I can get a fuller fill if no booster is around and that I don't have to swap out argon bottles as often.

The disadvantage is that it is a bigger and longer bottle. I usually don't notice it, but every so often, I might have to slide the bottle up to get it away from my left hip d-ring.

 

[TSandM]

I've been using a 6cf Al argon tank, and I can usually get three dives off it. But I'm little.

I have mine set up the way Doc illustrates, except that the bands I use I bought from my LDS, and they're not quite as fancy as the Halcyon ones (which are really nice, but like most things Halcyon, rather pricey). Mine don't have Velcro -- They're just a nylon strap band of the correct length, with grommets and a bolt to go through the backplate.

 

[Peter_C]

Do It Easy, do you have a picture of your setup mounted?

At what pressure do you folks refill your bottle? Can you consistently get 6 dives out of a LP14? Are you getting them filled at dive shops or do you get fills at welding shops and places like Praxair?

I too am about to get an Argon setup to keep me warmer, and extend my bottom times when using a single HP100. So I have read Argon will not affect buoyancy as much as air, which would also be a benefit.

 

[dsteding]

So I have read Argon will not affect buoyancy as much as air, which would also be a benefit.

Huh? Whoever told you this is on crack.

Most technical dive shops will fill argon, or you can rent a T from your welding supplier and get a transfill whip and appropriate fittings. One advantage of an LP14 is that you can transfill out of a T and get good fills for a while, and get lots of dives off of one bottle (I usually use ~2 cubic feet for a squarish profile, 100 foot, dive).

 

[do it easy]

Do It Easy, do you have a picture of your setup mounted?

At what pressure do you folks refill your bottle? Can you consistently get 6 dives out of a LP14? Are you getting them filled at dive shops or do you get fills at welding shops and places like Praxair?

I too am about to get an Argon setup to keep me warmer, and extend my bottom times when using a single HP100. So I have read Argon will not affect buoyancy as much as air, which would also be a benefit.

My "setup" is literally two loops- I just push the loop through the hole in the backplate and the knot keeps it from running through. I have to make sure not to trap the knot under the backplate or else it won't sit right. If you are really paranoid, or want to tie smaller knots, you could just choke the loop through the hole in the backplate and it would be secure, as long as you don't lose your argon bottle :11: In either case, the loops can be installed or removed in seconds without tools and both are can be cut.

I also made sure that the smaller loop was too small to let the tank slide through. In other words, it's big enough to slide over the valve, but not big enough to get past the neck. This might requrie a modification for a smaller tank.

With my AL14, I would start a rec dive with at least 500 psi which is about 3.5 cft. For comparison, an AL6 with 2000 psi (transfilled, no booster) has 4 cft.

I'm not sure how argon would make buoyancy control easier, but if it works for you, go for it. I suppose if you had a dedicated drysuit reg that was detuned, it would give you more control about how much juice you put in your drysuit, but this has little to do with argon or air. I detune my dedicated drysuit reg to 120 psi (I think?) and it fills my drysuit slowly.