DIR and SPG

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Rainer

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I've recently gotten a small brass SPG w/ 24" hose to replace my depth gauge and old SPG. The SPG is attached to a bolt snap in the DIR style (to my hip D-ring). I've been having some difficulty un/clipping it. I dive dry with either wet or dry gloves (will dive only the latter once I figure out what I'm doing to flood the dry gloves, but that's a different topic). Any advice for making this easier? Also, the hose length seems short (this is with a single tank only). Even unclipped, I can barely raise it closer to my face then when it's clipped off. The last couple of dives the combination of these two factors has simply led me to leave it clipped off and tilt my head down to check. While this works for now, it's not really an option if I ever need to sling tanks.

Now for a somewhat related question (but I'd prefer seperate answers for this and the above if possible). I was diving in San Diego this week, and one of the guys we were diving with ran his bare brass SPG in a way I hadn't seen before. He had it come off the first stage, ran it along the inflator hose (under a few pieces of intertube), with it ending just past the power inflator. It was remarkably streamlined, and presents a solution in which the SPG is always immediately viewable (even the fastest unclipper isn't going to beat glancing to the side). I'm wondering what you all see as the cons of diving the SPG this way. I'm looking for DIR answers, and that does NOT include (1) it's not DIR, or (2) it's solving a skills problem with an equipment choice. I want to understand WHY the hip method is prefered over the above.

Thanks!

Edit: Slight wording problem.
 
Rainer:
I've recently gotten a small brass SPG w/ 24" hose to replace my depth gauge and old SPG. The SPG is attached to a bolt snap in the DIR style (to my hip D-ring). I've been having some difficulty un/clipping it. I dive dry with either wet or dry gloves (will dive only the latter once I figure out what I'm doing to flood the dry gloves, but that's a different topic). Any advice for making this easier? Also, the hose length seems short (this is with a single tank only). Even unclipped, I can barely raise it closer to my face then when it's unclipped. The last couple of dives the combination of these two factors has simply led me to leave it clipped off and tilt my head down to check. While this works for now, it's not really an option if I ever need to sling tanks.

24" is too short for single tanks. Go to something a bit longer and see if things get easier. It's also good to have someone video you so that you can see what's going on and understand why it's difficult.

Now for a somewhat related question (but I'd prefer seperate answers for this and the above if possible). I was diving in San Diego this week, and one of the guys we were diving with ran his bare brass SPG in a way I hadn't seen before. He had it come off the first stage, ran it along the inflator hose (under a few pieces of intertube), with it ending just past the power inflator. It was remarkably streamlined, and presents a solution in which the SPG is always immediately viewable (even the fastest unclipper isn't going to beat glancing to the side). I'm wondering what you all see as the cons of diving the SPG this way. I'm looking for DIR answers, and that does NOT include (1) it's not DIR, or (2) it's solving a skills problem with an equipment choice. I want to understand WHY the hip method is prefered over the above.

One of the answers is (2) but since you don't want that I would ask a GUE instructor or post to Quest if you are a member.
 
nadwidny:
24" is too short for single tanks. Go to something a bit longer and see if things get easier. It's also good to have someone video you so that you can see what's going on and understand why it's difficult.

Would 26" be a good place to start?

One of the answers is (2) but since you don't want that I would ask a GUE instructor or post to Quest if you are a member.

(2) seems to only be an answer ONCE someone justifies why the hip method is inherently better. Otherwise someone could claim the relevant skill is just reading the SPG which is attached to the inflator! :wink:

Thanks!
 
Rainer:
I've recently gotten a small brass SPG w/ 24" hose to replace my depth gauge and old SPG. I've been having some difficulty un/clipping it. Any advice for making this easier?
Practice, practice, practice - you didn't mention how many dives you'd done since adopting this config, but you need to give yourself a little time to adjust to it. In particular, clipping and unclipping with gloves is kind of clunky at first, but you will get better at it with time and repetition.

It's also possible that (as someone else suggested) you may need a longer HP hose. The 24" seems to work pretty well on a singles rig with Scubapro regs (where the first stage tends to angle things down a bit more). If you're using an Apeks or something similar, then a longer hose might do better. I'd work with what you have for a while first before changing hoses, though. Getting someone to "eyeball" things underwater is a good suggestion too, and video is even better, if you have access to a buddy with an U/W camera.

Rainer:
I was diving in San Diego this week, and one of the guys we were diving with ran his bare brass SPG in a way I hadn't seen before. He had it come off the first stage, ran it along the inflator hose (under a few pieces of intertube), with it ending just past the power inflator.
One of the hallmarks of the DIR config is that you do not need to change the base system as you add equipment and increase the complexity of your dives. The SPG is placed with this concept in mind.

At this point in your training, you are using back gas as your primary gas supply, so you that's what you have to check. At higher levels of training however, the back gas effectively becomes your "backup" gas supply, and most of your diving is done with stage bottles. At that point, there's usually no reason to reference the back gas SPG during a dive (since you're not really using that gas), so the SPG can stay happily clipped to your hip D-ring, where it is out of the way. Having the SPG stuck on the inflator would tend to increase the clutter in that area, for no additional benefit.

One other thing to be aware of is that once you get dialed in on your air consumption, you learn to rely less and less on your SPG to keep track of your remaining gas, and use your bottom timer more and more (which is right on your wrist in plain sight). I rarely check my SPG any more during a dive, except to verify what I have already estimated from my depth and elapsed bottom time. In that respect, the SPG is somewhat superfluous, and you shouldn't really need it right in front of you all the time.
 
First question:

A 26" hose is very nice for singles. The 24" is for doubles. When I first started I had a 24" and it was a pain. I then used a larger bolt snap. This helped a lot in clipping and unclipping it with the 26". It didn't take long before I went back to the normal size bolt snap.

Second Question:
Could your buddy read your SPG on a short hose on your shoulder during an airshare? That might be a problem.
I think it would take me some practice to get used to having the SPG next to where I clip off the top of a deco bottle as well. Also like the fact that in the normal configuration, the only hose on your left shoulder is your inflator hose.
 
I too ended up abondoning the 24" hose on my single tank and use a 26". The extra 2 inches made all the difference.

My cavern instructor (GDI) had his spg on the inflator hose like you mentioned. I can see the merit in DIR-Atlanta's explanation above, but I have to admit it seemed like a pretty slick and streamlined setup. During air shares, it was easy for me to read his pressure as long as we where facing each other. Though I suppose during a single file exit, I wouldn't be able to read it, but I'm not sure if I would anyways if on a 24" hose?
 
maybe having the spg on the inflator hose would suck if the hose or an o-ring blows. lots of bubbles in your face and you might get whipped in the face. just a guess. since it has not happened to me i don't really know what it would be like.
 
JasonH20:
My cavern instructor (GDI) had his spg on the inflator hose like you mentioned. I can see the merit in DIR-Atlanta's explanation above, but I have to admit it seemed like a pretty slick and streamlined setup. During air shares, it was easy for me to read his pressure as long as we where facing each other. Though I suppose during a single file exit, I wouldn't be able to read it, but I'm not sure if I would anyways if on a 24" hose?

During air shares the receiver really has no need to see the SPG. Since the dive is immediately turned if an OOG situation pops up, either the team has enough gas to make the exit or they don't. Being able to see the SPG doesn't change that fact.
 
Another idea . . . In addition to putting a larger bolt snap on my SPG, I've also found it VERY important where that left hip D-ring is. If it's even a little bit too far forward (or worse, back) then it's very difficult to find. If it's perfectly positioned, you may never actually feel it, but you can hook into it because you know where it is.

I empathize. I've spent many minutes on many dives ineffectually trolling for my hip D-ring once I've checked my gauge. I've even had buddies come and hook it up for me, which is humiliation in spades. But this is a problem that can be solved with the right postioning and practice.
 
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