JimC
April 13th, 2007, 11:47 AM
Firing up your favorite search engine and plugging in a few combinations of backmount scuba dir hog configuration will deluge you with page after page of almost identical, well thought out and very effective configurations. Heck, there are even a few books out that tell you how to do everything. Do the same for sidemount and you get nothing - almost nothing. What you do get is a mishmash of indigestible information. So, here is my attempt at talking about configuring up a sidemount rig for cave and open water diving. I will only cover Floridian style sidemount with minimal, short term bottle removal using ether the Nomad, Armadillo or similar. I feel this should adequately cover the vast majority of sidemount newbies configuration needs. I will attempt to cover what I feel is the best method and also cover popular options. I will miss things, and I won't always be right. Sidemount configuration is very much personal preference and there is no one configuration that is simply superior in most ways.
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Tank Selection
The first thing about sidemount tank selection that must be understood is that you MUST size the tanks appropriately for your body size. Due to the positioning a big tank on a small diver will unbalance them in the water making it night-impossible to archive correct trim or move efficiently. Often the correct/best tank is something sized in the OMS LP85 or PST E7-100 range. The only way to tell is to try it. I can handle PST E8-119's, but 130's are to long and make it very difficult to get into good trim for me. But everyone is different and the best way to got is to try various tanks. The usual recommendation is, however, to start with an LP85 and work from there. Ideally each tank as 1/2 of a manifold post, plugged. You want a left and a right valve so that the valve handle can point down on each size. The tanks should be mirrors.
Often the tank chosen is smaller than what the diver was useing on backmount. This is often not an issue, as a sidemount team is relived from gas matching as a sidemount diver carries his own, fully redundant independent reserve gas and often find they can travel much more efficiently and go further on the smaller tanks. A problem occurs here in a mixed team, which can be solved in one of two ways; buddy bottle or limited penetration and adding a longhose.
Regulator Selection and Hose Routing
Virtually any regulator can be setup to be used comfortable in sidemount. So, anything you would chose for backmount can be used. You required two first stages, two second stages, two spg's and one or two LP hoses for buoyancy and/or drysuit. Each first stage needs one second stage, one spg and one or no LP hose.
SPG: Routed up, down or sideways on a 6 inch hose, depending on regulator shape. You want the SPG to sit ether against the tank, chest or shoulder area. Selection of which orientation is dictated by your first stage and what you feel comfortable with. The key point is that it is out of the way, doesn't dangle down when you are horizontal in the water and you can read it without to much fuss.
LP Hoses: Should be appropriately sized and routed under harnesses and out of the way. About the only thing to watch for here is hose kinks and dangling.
Second Stage: Routed from the tank, straight to mouth. Usually an elbow or swivel is needed to create a comfortable fit. Hoses in the 22 inch range seem to fit most divers comfortably. There are many many many alternative ways to route and park these. Most often then are simply clipped off to a shoulder d-ring, clipped off to a necklace, bunged down to shoulder or necklace. Key is that it be comfortable to breath, that it park cleanly without clutter, that all hoses are clean and not dangling and that regulators are tucked in tight and not allowed to dangle. One finally note on second stages; screen should be placed inside the mouth bitedown of each to prevent sharp limestone and shells from being inhaled and help prevent scooping up mud and silt into the regulator body.
In a mixed team, if you are expected to donate gas for an exit you must have a long hose somewhere. I feel the best place for this is a third second stage, with the long hose bunged to one of the tanks.
Things that I find don't work, mostly due to bottle removal needs. Wrapped hose; Some people attempt to route a long hose ala hog and wrap it around there neck securing the remainder ether with placements or bungee. Some also utilize a stage length hose and place that on a bungee under there chin. Often this is newer sidemount divers and often they combine both wrapped hoses simultaneously. This method works until you are required to remove one or both tanks. Dealing with the wrapped hoses extra length and/or neck bungee adds an enormous amount of task loading to an already complicated process. It is however, probably the most common hose routing currently in use on sidemount. It does allow you to maintain some of the muscle memory from backmount but adds some very error prone complications such as, which reg am I breathing, which to donate and worst, IMHO, boltsnap manipulation which is difficult with gloves and could be jammed or seized.
Can Light
The first question you must ask your self is where you are going to put the light cannister. No sidemount rig allows you to just feed it onto the harness as with backmount. Simply the wrap around of the buoyancy cell comes around your waist to far and that will leave the canlight front and center, dragging across everything. This leaves you with two places; your butt or under the wing. Butt mounting is very common and easy to accomplish but you may find you need a new light cord, a longer one. Under the wing takes some customization and fiddling and you have tweak the placement until you find a location that is comfortable. Both methods work, I tuck my can under my left shoulder about where most backmounters would wear their wreck argon.
Accessories
I will be right out honest with you. In my opinion the only place for 'stuff' is still in pockets. Thigh pockets are a pain in the ass to get to on sidemount as there is a tank sitting ontop of the pocket. This still, for me, is the only place to stow stuff and I just deal with them being harder to get at.
However, lots and lots of people clip spools and stuff off to there rear d-ring or on their back. I do not advocate this, as its just a matter of time until, like me, you have a failed primary, and 50 feet of line warped around you, your fins and the cave. Fixing that on a backup light was an eye opener and I have never since put a spool on my back in a cave. They WILL scrap off on the ceiling and they WILL do their worst.
Tank Placement
One tank on each size. Most people use a camband arrangement on the lower end of each tank with a clip of some sort on it. A hose clamp can suffice and I might even say would be more secure and solid, but the camband works. I once used ducttape in a jam - but that isn't best practice by any means.
The type of clip you use is for the most part irrelevant what is relevant is that its tight and doesn't allow the tank to slide around much. You want the tank to stay put and be in line, horizontally with your body.
The neck of the tank should be under your armpit, in line with your body such that the tank rides parallel to you, along your side. One thing to watch for is to much flaring at the hip. A bit of flaring outwards is unavoidable, but the further they flare out the bigger your profile is. Ideally they should sit right up against your body, parallel to you without moving around and they should not interfere with your frog kick.
I think thats all the big topics, and my fingers are getting sore.
===========
Tank Selection
The first thing about sidemount tank selection that must be understood is that you MUST size the tanks appropriately for your body size. Due to the positioning a big tank on a small diver will unbalance them in the water making it night-impossible to archive correct trim or move efficiently. Often the correct/best tank is something sized in the OMS LP85 or PST E7-100 range. The only way to tell is to try it. I can handle PST E8-119's, but 130's are to long and make it very difficult to get into good trim for me. But everyone is different and the best way to got is to try various tanks. The usual recommendation is, however, to start with an LP85 and work from there. Ideally each tank as 1/2 of a manifold post, plugged. You want a left and a right valve so that the valve handle can point down on each size. The tanks should be mirrors.
Often the tank chosen is smaller than what the diver was useing on backmount. This is often not an issue, as a sidemount team is relived from gas matching as a sidemount diver carries his own, fully redundant independent reserve gas and often find they can travel much more efficiently and go further on the smaller tanks. A problem occurs here in a mixed team, which can be solved in one of two ways; buddy bottle or limited penetration and adding a longhose.
Regulator Selection and Hose Routing
Virtually any regulator can be setup to be used comfortable in sidemount. So, anything you would chose for backmount can be used. You required two first stages, two second stages, two spg's and one or two LP hoses for buoyancy and/or drysuit. Each first stage needs one second stage, one spg and one or no LP hose.
SPG: Routed up, down or sideways on a 6 inch hose, depending on regulator shape. You want the SPG to sit ether against the tank, chest or shoulder area. Selection of which orientation is dictated by your first stage and what you feel comfortable with. The key point is that it is out of the way, doesn't dangle down when you are horizontal in the water and you can read it without to much fuss.
LP Hoses: Should be appropriately sized and routed under harnesses and out of the way. About the only thing to watch for here is hose kinks and dangling.
Second Stage: Routed from the tank, straight to mouth. Usually an elbow or swivel is needed to create a comfortable fit. Hoses in the 22 inch range seem to fit most divers comfortably. There are many many many alternative ways to route and park these. Most often then are simply clipped off to a shoulder d-ring, clipped off to a necklace, bunged down to shoulder or necklace. Key is that it be comfortable to breath, that it park cleanly without clutter, that all hoses are clean and not dangling and that regulators are tucked in tight and not allowed to dangle. One finally note on second stages; screen should be placed inside the mouth bitedown of each to prevent sharp limestone and shells from being inhaled and help prevent scooping up mud and silt into the regulator body.
In a mixed team, if you are expected to donate gas for an exit you must have a long hose somewhere. I feel the best place for this is a third second stage, with the long hose bunged to one of the tanks.
Things that I find don't work, mostly due to bottle removal needs. Wrapped hose; Some people attempt to route a long hose ala hog and wrap it around there neck securing the remainder ether with placements or bungee. Some also utilize a stage length hose and place that on a bungee under there chin. Often this is newer sidemount divers and often they combine both wrapped hoses simultaneously. This method works until you are required to remove one or both tanks. Dealing with the wrapped hoses extra length and/or neck bungee adds an enormous amount of task loading to an already complicated process. It is however, probably the most common hose routing currently in use on sidemount. It does allow you to maintain some of the muscle memory from backmount but adds some very error prone complications such as, which reg am I breathing, which to donate and worst, IMHO, boltsnap manipulation which is difficult with gloves and could be jammed or seized.
Can Light
The first question you must ask your self is where you are going to put the light cannister. No sidemount rig allows you to just feed it onto the harness as with backmount. Simply the wrap around of the buoyancy cell comes around your waist to far and that will leave the canlight front and center, dragging across everything. This leaves you with two places; your butt or under the wing. Butt mounting is very common and easy to accomplish but you may find you need a new light cord, a longer one. Under the wing takes some customization and fiddling and you have tweak the placement until you find a location that is comfortable. Both methods work, I tuck my can under my left shoulder about where most backmounters would wear their wreck argon.
Accessories
I will be right out honest with you. In my opinion the only place for 'stuff' is still in pockets. Thigh pockets are a pain in the ass to get to on sidemount as there is a tank sitting ontop of the pocket. This still, for me, is the only place to stow stuff and I just deal with them being harder to get at.
However, lots and lots of people clip spools and stuff off to there rear d-ring or on their back. I do not advocate this, as its just a matter of time until, like me, you have a failed primary, and 50 feet of line warped around you, your fins and the cave. Fixing that on a backup light was an eye opener and I have never since put a spool on my back in a cave. They WILL scrap off on the ceiling and they WILL do their worst.
Tank Placement
One tank on each size. Most people use a camband arrangement on the lower end of each tank with a clip of some sort on it. A hose clamp can suffice and I might even say would be more secure and solid, but the camband works. I once used ducttape in a jam - but that isn't best practice by any means.
The type of clip you use is for the most part irrelevant what is relevant is that its tight and doesn't allow the tank to slide around much. You want the tank to stay put and be in line, horizontally with your body.
The neck of the tank should be under your armpit, in line with your body such that the tank rides parallel to you, along your side. One thing to watch for is to much flaring at the hip. A bit of flaring outwards is unavoidable, but the further they flare out the bigger your profile is. Ideally they should sit right up against your body, parallel to you without moving around and they should not interfere with your frog kick.
I think thats all the big topics, and my fingers are getting sore.