But by all means keep the ponies. 
Wing trim roll issue
- Thread starter Rick Inman
- Start date
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From someone consdiering making the switch to BP/W, is this rolling a common issue? If someone were diving with a singe pony (13 or 19) which would be my configuration, is that a difficult scenario to counterbalance?
In my estimation, an attractive primary benefit to the BP/W system was to unclutter the frontal torso. If a diver such as this poster has to put weights near his belly for ballast, seems like some of that original benefit is lost.(?)
JAG
In my estimation, an attractive primary benefit to the BP/W system was to unclutter the frontal torso. If a diver such as this poster has to put weights near his belly for ballast, seems like some of that original benefit is lost.(?)
JAG
I have to wonder if the two little 13's are causing some disturbance here. Humor us and do a dive or two without them, and report back on your findings. I dont believe the STA is the culprit.
jagfish:
Well, in order to not turn this thread into another "Pony or NO-Pony" thread, I will just say that when I am diving a single tank configuration, its just that. A single tank. If you do need a pony, then try a few different ways of managing it. If you stick it on your back, strapped or otherwise connected to your primary cylinder, you may notice being tipsy to that side. You might have to correct that by putting a counterbalance on the other side (move some of your required lead to the other side). Some people like to sling the pony as a stage bottle. However, seeing as a 13 is a itsy bitsy cylinder, I dont think this option would work very effectively.
LUBOLD8431:
I visited this area a couple of months ago and I do not want the same arguments to occur.
That being said,
The STA is putting the tank much further away from your back than a set of doubles would sit. The closer the tank is to your back, the better your center of gravity, the less likely you are to have the rolling effect.
There are a couple of manufacturers other than "my manufacturer of choice" who make BP that are designed to be STA-less.
Matthew J D'Avella
OP
Uncle Pug:But by all means keep the ponies.
LUBOLD8431:
Alright, tonight's dive will be sans ponies and I'll post tomorrow.
OP
Report from last night's dive:Rick Inman:
Freshwater dive. I made the dive without the ponys and lowered the tank as much as the top STA would allow. I started by putting 10 pounds into my weight belt and put a bunch of different weights onto the dock to play with before the dive. I ended up just slightly light at the end of the dive by adding another 4 pounds to my weight pockets. So, total weight (not counting BP and tank), 14 pounds.
There was definitely a great improvement without the ponies. Still a slight tendency to roll over, but very little, certainly manageable.
So, as the water is now warming back up, I can easily lose the argon pony for a while, but I'll still want the bailout pony back in my configuration. I'm thinking that I may be mounting the thing too far back also, and so I guess I'll try moving it forward against the wing, and maybe down on the tank as well. But it sure was better last night.
LioKai:
I have two STA's and they both work fine. I never get that feeling of turtling. I dont know what everyone's problem is with an STA. Never messed my dive up. BTW, do you actually know the distance that a FREDT STA actually brings the cylinder away from your back? I mean, we are not talking about a big number here, its less than half an inch.
Rick Inman:
Sounds like you had a better night of it. You ended up with 14# in additional weight to your rig compared to 16# and two 1-2# AL tanks before, so that is a saving of aroud 4-6#, and once you bottles go back on you will have 10-12# i would imagine in weightbelt/pocket weight. Still dont know enough about drysuit diving to say whether the total weight of the rig and additional weights is reasonable though, but that is what practice and playing around in a safe environment can do!!
Even though i feel i have got a pretty good handle on my weighting with a couple of different tanks, i still seem to have to add a ton of weight when i do the shallow sharks teeth dives down here in the gulf - still dont know why i have to add so much to stay down there, its like the OW pool thing all over again!
Rick,
As noted, the reason for the instability is that the longitudinal axis of the tank (and combined weight "above" you) is high enough above the longitudinal axis of your body that when you roll laterally that weight wants to continue rolling laterally.
Best thing to do is reduce the height of the (longitudinal axis of the) weight above you. Best way to do that, initially, is to reduce weight period - to an extent that is safe.
Next thing is to improve lateral stability by re-locating weight - including bottles. On the bottles. One of the better ways to carry argon is with a 6 cu ft tank attached to the backplate along the left side. UP has a series of photos of a mount he made. It works well, and doesn't cost much. If you want one that works well and costs a whole bunch, check this one out:
http://www.halcyon.net/exposure/accessories01.shtml
Halfway down, the 6cuft item: photo is not good, but the two small bands bolt to the side of the bp.
If you're going to carry a bailout bottle, one of the best ways to do so is slung as a deco bottle. This allows you to ensure that no gas loss will occur (by turning off the valve), but that you can turn the tank on and use it rapidly as the valve is in front of you. Also, if hung up or entangled, you can more easily remove or untangle a situation that you can get at and see. Additionally, this puts the weight of the valve and regulator down beneath you instead of to the side off your single - which adds to lateral instability.
FWIW. YMMV.
As noted, the reason for the instability is that the longitudinal axis of the tank (and combined weight "above" you) is high enough above the longitudinal axis of your body that when you roll laterally that weight wants to continue rolling laterally.
Best thing to do is reduce the height of the (longitudinal axis of the) weight above you. Best way to do that, initially, is to reduce weight period - to an extent that is safe.
Next thing is to improve lateral stability by re-locating weight - including bottles. On the bottles. One of the better ways to carry argon is with a 6 cu ft tank attached to the backplate along the left side. UP has a series of photos of a mount he made. It works well, and doesn't cost much. If you want one that works well and costs a whole bunch, check this one out:
http://www.halcyon.net/exposure/accessories01.shtml
Halfway down, the 6cuft item: photo is not good, but the two small bands bolt to the side of the bp.
If you're going to carry a bailout bottle, one of the best ways to do so is slung as a deco bottle. This allows you to ensure that no gas loss will occur (by turning off the valve), but that you can turn the tank on and use it rapidly as the valve is in front of you. Also, if hung up or entangled, you can more easily remove or untangle a situation that you can get at and see. Additionally, this puts the weight of the valve and regulator down beneath you instead of to the side off your single - which adds to lateral instability.
FWIW. YMMV.
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