First stage, face up or down? Also, SPG sticking up or under the arm?

[scuba127]

Thanks Texasguy. Are you wrapping the loop bungee around the valve handle subcooled? If so, are you having any issues with it....tank rotation etc?

 

[Texasguy]

I was diving unmodified vanilla SMS100 with some of my own mods, however, I sent and just received modified rig from caveadventures, will dive on Sunday, I'll try out "old school" bungee system and will let you know.

PS: Had no problem with original bungee method, though.

 

[scuba127]

Thanks...

 

[djcheburashka]

subcooled: the difficulty I had doing it that way, is that the boltsnap from the neck of the stage bottle to the chest d-ring doesn't clear the first stage enough to be manipulated unless it's on a leash that then throws off the tank trim.

How do you deal with that issue?

 

[Subcooled]

My side mounted tanks have no boltsnaps in the upper end (neck). I just stretch the bungees a bit (down & out) and then drop the tank in. The bungee just goes around the rubber knob once. The valves are dead easy to operate as the knobs point down. The lower attachment point needs to be at 45 deg angle though and note that I use negative steel cylinders in cold water (-1 to +4 C). Lots of undergarments and air... No experience with wetsuits and Al80...

Decompression/stage gas cylinders carried below the diver may complicate things by not allowing the opposite hand to be used to manipulate valves (over the chest).

 

[djcheburashka]

I think I almost sort of get you...very different config. I'm talking about a pair of al40s or 80s for deco under the sm tanks. Thank you.

 

[Subcooled]

For that I am using "Lumb brothers heavy duty stage bottle carrying strap." Don't know if that would help.

 

[Texasguy]

So, tried my SMS100 with 2 modifications done at caveadventures, the wing tightening and old school bungees. The rig has 2 of my own mods, valve reversal and exhaust string routing.

So, my very first hope was that I would shed weight. (I am diving aluminums with 2# on each bottle , btw). Nope, same 6# in addition to the tank weights. So, weight wise no difference.

Old school bungee mod does feel better but the difference is not that extreme. I do find that it is easier to put a bungee over a valve.

 

[tbone1004]

why do you think that you would shed weight? you aren't doing anything to change the buoyancy of the rig or you, the tightening of the wing only relates to fixing what is otherwise a horrible wing design. With twin 80's, you need 6lbs of lead to offset the buoyancy of the tanks when they're empty anyway *9lbs of total positive buoyancy, less about 1.5lbs/first stage and another 1lb/side if you're using metal cam bands*, most people need on average 2-4lbs of lead to sink themselves, and the sms100 needs at least 1lb to sink it, so you're doing pretty good in that respect.

Old school bungees are two fold. The webbing spacer helps to keep the bungee from pinching the bladder which keeps air from moving around and is bad, and the loops keep the valves up tighter which serve the sole function of raising the valves so they are inline with your torso. It's aesthetics as well as slightly increasing the efficiency of the rig. Get someone to take a video of you doing flat turns in the pool so you can see both sides and post them here, we might be able to help you make some more adjustments.

 

[Dive Right In Scuba 2]

Personally I go 1st stages down, gauges up. It just seemed to "settle" that way after many many dives of tweaking and peeking. The cool thing about sidemount is it's so user friendly.