Sidemount with deco bottles

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GAdiver

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81
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Location
Georgia
# of dives
500 - 999
i have recently taken ART and during the class I was using backmount-style stage rigging, even though I was diving sidemount, is there a better way to do this? Also I was looking at running an inflation hose for my drysuit off my deco cylinder for when I'm diving trimix (It's filled with 50% if this matters) and I've found conflicting answers on whether it's okay to do this or not; is it okay when I'm doing a max of 15 minutes of deco on this bottle?
 
When i did ART (Backmount, not SM) I was told it's preferable to have an off-board Suit inflate, but if that's not an option, then the first alternative is to use suit inflate off of the deco bottle. So yes, i'd say that it's ok to do it, just not the ideal solution, but certainly better than running suit inflate from your TX cylinders.

NOTE: Obviously, remember to add enough gas to your deco bottle to account for the extra gas used! As a general rule, a suit inflate cylinder is a 1 or 1.5L cylinder, filled to max 232bar (sorry i'm UK, don't know in PSI) so working it back to litres, i'd say you need to add at least an extra 230 litres to your deco cylinder (assuming an Ali 80, that would be an extra 21 Bar, or an extra 33 Bar if using a 7L deco cylinder) on top of the gas planning you've done for the deco gas required to ensure you dodn't use any of the deco/reserve deco gas you've planned for the dive.

Hope that helps, and hope it makes sense....
 
Sorry, not Tech trained so may be a stupid question.
The use of your deco bottle to inflate your suit seems to be counter intuitive.
If there is a problem say a slow leak you might not know of this until you reach your deco stop. Possibly a very serious situation.
I thought it would be better to have your deco supply turned OFF until you required it and use your back gas to inflate. That way if something goes wrong you know about it at the time.
Just my 2c worth
 
i have recently taken ART and during the class I was using backmount-style stage rigging, even though I was diving sidemount, is there a better way to do this?
There are OTHER ways - whether they are better or not is up to the individual divers.

You can use standard rigging, but some (I am one of those) find it cumbersome to have the bottle hanging, so I find it useful to have an addition bungee to hold the neck / valve in tighter. There is also the question of where to position the bottle - 'outside' / 'on top of' the mains, or 'inside' / 'under' the mains.

I personally prefer using a bungee cord leash around the neck of the cylinder, and a bungee cord leash under the hose clamp at the base of the cylinder - the key difference being bungee cord rather than static line. I also mount my deco cylinder outside of the mains. That is NOT by any means a universal practice, and others have found mounting the deco bottle inboard to be better for them.
Also I was looking at running an inflation hose for my drysuit off my deco cylinder for when I'm diving trimix (It's filled with 50% if this matters) and I've found conflicting answers on whether it's okay to do this or not; is it okay when I'm doing a max of 15 minutes of deco on this bottle?
It is OK to do it. I don't. With either SM or BM, when using a drysuit, I carry a separate 6cf inflation bottle.

You might check some of the comments in others threads, on both subjects, e.g. http://www.scubaboard.com/forums/sidemount-diving/480060-argon-bottle-placement-sm.html
 
I personally like top mounting my deco bottles. I use rob neto's stage rigging setup and I find it works great. Keeps the bottle tight to my primary but also out of my way. I mark the MOD on the neck of the bottle as well as the regular side of the bottle that way I can verify the gas I am about to breathe and so can my teammates.

I don't like the way bottles attached to bottom feel. Personal preferance YMMV
 
I prefer to mount them on top as well and all of my bottles except O2 have inflator hoses on them. Mainly for checking IP but also in the offchance that I need to use one for suit or wing inflation in the case of a 1st stage/valve failure. With proper deco planning you usually have more than enough gas to inflate off of and some of the deeper deco mixes are usually cheap enough to use as an inflation gas. If you're diving properly you won't go through a whole lot of inflation gas anyway a few CF is negligible in the grand scheme of things, just plan it into your gas management. I try to avoid mix diving on OC now with He being so damn expensive, but I have yet to find a good place to stick an inflation bottle in sidemount so I just used whatever the cheapest deco mix I had for suit and wing inflation.
 
Sorry, not Tech trained so may be a stupid question.
The use of your deco bottle to inflate your suit seems to be counter intuitive.
If there is a problem say a slow leak you might not know of this until you reach your deco stop. Possibly a very serious situation.
I thought it would be better to have your deco supply turned OFF until you required it and use your back gas to inflate. That way if something goes wrong you know about it at the time.
Just my 2c worth

Not a stupid question for someone who hasn't taken trimix. Helium takes heat away from your body (correct me if i'm wrong y'all) 6x faster than air which would equate 2x faster diving 21/30 , and I am already diving in water between 40-50* F and I get cold pretty easily.


Sent from my iPhone using Tapatalk
 
If i'm on a boat i'll mount them on top, then move them to the bottom when im under.

With Alis, I use a sliding D-ring for my backgas, set in where it would be if the bottles were breathed down, behind I have a static D ring which i clip the stages to. The cylinders pull/push against themselves, keeping them streamlined at all times and they're still simple to don/doff.
 
Yea, I like his method for stage bottles too. However, as he also points out, attaching deco bottles topside is frowned upon cause it's more difficult to inspect it this way. But if you can manage it and are comfortable with it, it's your choice.

I personally like top mounting my deco bottles. I use rob neto's stage rigging setup and I find it works great. Keeps the bottle tight to my primary but also out of my way. I mark the MOD on the neck of the bottle as well as the regular side of the bottle that way I can verify the gas I am about to breathe and so can my teammates.

I don't like the way bottles attached to bottom feel. Personal preferance YMMV
 
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