'Open Water' only sidemount BCDs: Your opinions?

[Karl_H]

I just helped a friend set up a new Hollis sms50 today - the bottom LPI was too short for manual inflation. I would love to know the justification for this. Do some sm divers just assume they will never need to orally inflate the wing and, with this in mind, criticize a top LPI that allows such an option, as being unnecessary.

I see where you're coming from on this - I had a real problem with a ball of string for a long time too. I found it wasn't long enough to tie the two objects I was hoping to tie together, luckily I found soem similar string on the spool as I found as it was long enough. Wouldn't you know it turns out string comes in different lengths in both balls and spools.... You live and learn I guess

PS - Obviously this was before I discovered braided line, string just wasn't the same after that

 

[DaleC]

So you are saying it's up to the new OW SM user to know they have to modify a brand new rig because the way it comes to them is straight out unsafe? And this is a better solution for those divers than the top mounted LPI's they are used to why? So far, all I see are problems set up in using a system that in this application only solves an imaginary problem.

Your sarcasm falls short of the mark though as I am the guy who could dive with a bleach bottle and a pocket full of rocks (and I could build the bleach bottle) but what we are discussing is the pros and cons of top vs bottom LPI's. My thought was that the store bought Hollis rig had a con right off the get go.

 

[rjack321]

Causing "environmental damage" and "messing up my fun" are vastly different things. Population pressure and run off, and Ocean industry (inclduing commercial fishing) cause environmental damage. Bad buoyancy control just messes up what people want to see.

In the small way divers make damage, just getting in the water causes damage with the chemicals and chance for damage divers bring, and that does not really change that much from the best to the worst divers.

It would be nice if divers acting a certain way made a difference, but it really does not make much difference. It just messes with 'my view'. Large populations living near the ocean, and industrial action near or in the ocean makes a difference.

You obviously haven't seen some of the popular reefs in the tropics. Bad bouyancy is like a hurricane crashing into the reef day after day...

---------- Post added February 19th, 2013 at 10:12 AM ----------

So you are saying it's up to the new OW SM user to know they have to modify a brand new rig because the way it comes to them is straight out unsafe? And this is a better solution for those divers than the top mounted LPI's they are used to why? So far, all I see are problems set up in using a system that in this application only solves an imaginary problem.

Your sarcasm falls short of the mark though as I am the guy who could dive with a bleach bottle and a pocket full of rocks (and I could build the bleach bottle) but what we are discussing is the pros and cons of top vs bottom LPI's. My thought was that the store bought Hollis rig had a con right off the get go.

Almost every store bought SM rig has a "con". The worst are the unfixable ones like a poorly cut wing with too much lift up high (The DR JT comes to mind). Fortunately (by all accounts) this does not afflict the SMS50. Poor neck bungies and too short or too long corrugated hose are at least fixable.

 

[beanojones]

You obviously haven't seen some of the popular reefs in the tropics. Bad bouyancy is like a hurricane crashing into the reef day after day...

But that's just ruining the view. A good size parrotfish eats a ton of coral a year. Boat anchors and hurricanse do more damage than a thousand divers trying their hardest to do damage. Coral gets destroyed pretty regularly by all sorts of things and it just grows back.

I'm not saying don't have good buoyancy. It's just to say that it causes "environmental damage" and it's not just spoiling the view for other divers is really not understanding just how big the ocean is, and what environmental damage is.

 

[JamesK]

But that's just ruining the view. A good size parrotfish eats a ton of coral a year. Boat anchors and hurricanse do more damage than a thousand divers trying their hardest to do damage. Coral gets destroyed pretty regularly by all sorts of things and it just grows back.

I'm not saying don't have good buoyancy. It's just to say that it causes "environmental damage" and it's not just spoiling the view for other divers is really not understanding just how big the ocean is, and what environmental damage is.

I fully understand your point. However, to not bring it up is basically giving an ok to do it. The fact is it does harm life. Is it the biggest contributing factor? No. We all know that. However it is still harm. That is like me saying, "heck my 6.5 quarts of used synthetic motor oil is a splash in the bucket compared to the BP gulf disaster. Screw it, I will dump it in the creek behind my house."

Now I am far from an environmentalist, but I still try to do my part and leave things as good, if not better, then I see them.

 

[Karl_H]

So you are saying it's up to the new OW SM user to know they have to modify a brand new rig because the way it comes to them is straight out unsafe? And this is a better solution for those divers than the top mounted LPI's they are used to why? So far, all I see are problems set up in using a system that in this application only solves an imaginary problem.

I think this is a great reason to illustrate why people should take a sidemount course or at least do some research before buying gear.

The sarcasm wasn't intended to be offensive, I'm just trying to make the point a lot of people obviously aren't ready to dive sidemount without supervision if they can't see the obvious solution to the problem you mention.

 

[DaleC]

I think that's valid. To me the appeal of sm is the do it yourself aspect that allows for a lot of modding so issues like that don't bug me.

 

[DevonDiver]

So you are saying it's up to the new OW SM user to know they have to modify a brand new rig because the way it comes to them is straight out unsafe?

I think it's up to the instructor. I certainly spend time with students to help them optimize their gear and show them all the tips and tricks.

Given the large variations in SM Rig approach, there's no substitute for gaining instruction in your specific rig. A good SM instructor can, and will, help fix such deficits and educate the diver on more general principles they can apply in later stages.

Of course... if a diver opted to buy some random SM rig without researching it's optimal use... and/or seeking out a credible educator to help them... it'd be fair to place the blame for any frustrations, failings and fluster on the rig itself...or the more general attributes of SM as a diving system? I see...

The issue of top vs bottom LPI's falls nicely into this specific debate. As I mentioned much earlier in the thread... those that seek the 'quick fix' of an LPI position that equates to their prior back-mounted experience...and conduct said training in that configuration.... leave themselves markedly under-trained should they subsequently progress onto a SM rig/config with a bottom LPI. No doubt, that lack of capability would be the rig's fault too......

 

[DaleC]

How so? It doesn't take very long to learn how to operate a bottom mount LPI.
But what quick fix are you talking about? For OW, which the rig is designed for, there is no need for a bottom LPI. What you are doing is transplanting the requirements of one regime into another.

OW sm is OW sm, not bastardized cave sm. You keep thinking they are suppressing something but it's just that they don't need it - in OW the LPI position is a non essential option.

 

[Karl_H]

The choice of over or under for the corrogated hose is really up to the owner, and it does change from person to person. When we were using MSR bags for BCs here (Before any reasonable warm water bladder was available) we still has some students who preferred the MSR bag running along the spine rather than across the back - the corrugated hose tended to work better over the shoulder for this configuration rather than from the bottom of the MSR bag, a dump valve was added to the bottom.

The hose routing really depends on which bungees are used, wrap around bungees like the razor style make a 5th port LPI really nice to route, hence bottom mounting may be easier. If the bungees keep the tanks further down the body (like the standard nomad) then it doesn't really make too much difference if the corrugated hose is run over the shoulder or under in all honesty.

I got to dive with someone using a Nomad LT harness for the first time this week, it seemed to work okay with the corrugated hose over the shoulder, but moving the corrugated hose to the original dump valve position was a disaster - basically you need to loose all trim to dump air. It's actually much better for trim when used with a over the shoulder corrugated hose - that said, I'd say that was a major design fault than a general rule!

Over the shoulder would also make life easier for anyone who wants to mount a tank on either the left or right side when using single tank sidemount - I'm not saying it's the right approach but it would make things easier.