LP Drysuit Fill

[Parsons]

Was not sure were to post but here we go. Diving with doubles and moving to the first stages of Trimix. Was thinking 13cf tank with air for the Drysuit. But I have heard of people using a low presure hose off there stage bottle for the drysuit fill. I like the way my setup is diving as it is now. Just adding a lp hose is not much of a change. All opinoins are welcome.

DP

 

[flots am]

Was not sure were to post but here we go. Diving with doubles and moving to the first stages of Trimix. Was thinking 13cf tank with air for the Drysuit. But I have heard of people using a low presure hose off there stage bottle for the drysuit fill. I like the way my setup is diving as it is now. Just adding a lp hose is not much of a change. All opinoins are welcome.

DP

What's wrong with using your back gas? Why make things more complicated?

If you really want a separate tank, you can get a tiny ~6cuft tank and fill it with argon, which insulates a little better, but all things considered I'd rather just put on thicker underwear.

flots.

 

[Jim Lapenta]

If you are heading into mix you don't want to use back gas for the drysuit if you can avoid it. Isobaric counterdiffusion is a term you will learn. Most divers I know use a suit bottle of either 6 or 13 cu ft. I switched from a 13 to a 6. Much more compact and still enough gas for dry suit. I have never heard of anyome running a suit off of their stage. Can't imagine why they would. Especially if you may need to hand it off, drop it and retrieve it, or why you would use deco gas for a drysuit.

One other thing is helium is a lousy insulator and will actually contribute to heat loss. And that includes when you breath it.

 

[Parsons]

I already have a 13 cf tank and maybe mounting it the the side of the doubles. To me that seems like thinks will be getting wide back there. I'm not planning on argon. 6cf, I would think is just enough for one dive.
I did not think about the heat lose when you breath Helium.
There are some divers using there deco gas. Just getting another opinion.

 

[PfcAJ]

An al6 is ideal for almost any dive, especially at the entry level. It's tucked out of the way and provides an adequate volume with a reasonable reserve. Air is ok for suit inflation, but argon probably would provide some benefit if the water was real cold, your dives were long, and its easy to obtain. I use argon because I can get it easily. If I couldn't, I would use air without hesitation. The al6 will probably last you a few dives, but it behooves you to check it before the dive.

I would NOT put it on a stage/ deco bottle, a backplate mounted bottle is a far better choice. Anything that you might have to drop or handoff is a poor choice for something like suit inflation, and I think there is value in keeping all your stage/ deco regs logistically equivalent.

If your dives start to get longer or you move to longer/deeper cave diving at some point in the future, the al14 (2015 service pressure) mounted on the backgas tanks becomes the tool of choice. While the 13 and 14 only differ by "1", the 14 actually holds a lot more gas due to its lower service pressure. Argon usually comes in relatively low pressure supply bottles, so you'd have to boost the argon to get a reasonable volume in the al13, and a lot of places can't or won't boost argon.

 

[boulderjohn]

I am with PfcAJ.

I use an AL6 on my backplate frequently, and it is usually good for a couple of regular dives. I have an AL 13 that I can mount on my tanks, but I haven't used it in a long time. I will use argon when it is readily available, but air usually works fine. I often use "airgon," a bottle that started off as argon but slowly morphed toward air as I kept adding to it via transfills.

If I am not using trimix, I usually just run a hose off my back gas. It's much easier.

 

[ianr33]

I have never heard of anyome running a suit off of their stage. Can't imagine why they would. Especially if you may need to hand it off, drop it and retrieve it, or why you would use deco gas for a drysuit.

Never say never! I dive a particular cave once in a while. Max depth is 135. We normally use 27/20. Use the (side)gas for suit inflation. I'm fine during the dive but get cold on deco. I'm sure the helium is partly to blame. Thinking of sticking an inflator hose on the 50% bottle to see if it makes any difference. (would switch hoses after picking up the 50%)

 

[PfcAJ]

The logic there seems a bit backward, mate

 

[ianr33]

The logic there seems a bit backward, mate

?? Don't follow you.

 

[Dsix36]

You would have to flush your suit with the 50% to get the previous helium out in order to benefit from plugging in the 50% tank. No more gas than you would need for suit inflation, you would be better off to use only the 50% IMHO.