Horrible Divers Everywhere?

[Chavodel8en]

I never understood the idea that a jacket BC tends towards bad trim.

I mean, if you're underwater (and not over-weighted), there should be very little air in the BC, so the bubble shouldn't affect your trim. So if its not the bubble, its not really the BC at issue

This hasn't been my experience, but to each their own.

I totaly agree, I was just saying that I feel in a traditional jacket style, without weight towards my head, it pushes my toward a 45 if I'm not moving. I was under the impression that for the most part, this is what a traditional jacket does through reading others' experiences with them, and why they've switched to a bp/w.

- jake

So its really bad weighting that causes bad trim. In any BC, if you dont have your weights balanced, you will be in bad trim. True, w/ a BPW, you are likely to automatically be more balanced, just by the nature of a BPW. With a jacket, you will likely need trim weights. I used to dive a jacket BC, and it trimmed out fine, as long as I had weight in the trim pockets.

Now Im not defending jacket BCs. I don't like them - although not for trim reasons - I don't like how you go from feeling squeezed to feeling loose as you inflate & deflate.

But I think its not accurate to criticize them for "causing bad trim." Bad weighting causes bad trim, not any style of BC.

 

[Bob DBF]

Are you saying I am using it improperly by using a V/B weight with it or..?
I honestly can't tell.

I was just saying that I feel in a traditional jacket style, without weight towards my head, it pushes my toward a 45 if I'm not moving.

The wing with a weight belt without weight towards my head will do the same thing to me when using jet fins, not necessarily to 45 degrees, but the same principle. Take a portion of your ballast and put it where you need it, move the tank, or use more floaty fins, or combination of all of the above to adjust your trim to where you want it.


Bob

 

[loosenit2]

Let me start by saying I'm a recreation diver with the overpriced "advanced" card and the expensive nitrox card to go with it. I'm not a perfect diver, always working on something. My trim could use some work, still adjusting the final touches on my bp/w, but there are some things that I just DON'T do.

I live in MD so most of my experience is quarry diving. Thank goodness for quarries because there's little life to disturb and while it is REALLY frowned upon to crash into the bottom, it does happen at times, but for the most part I see divers avoiding it at all costs. There's platforms for that I guess.

I'm getting to my point. I'm here in FL and went diving at my FAVORITE place to dive, the Blue Heron Bridge. WTF? There were divers everywhere CRAWLING ON THE BOTTOM (I've never been on a weekend). Classes were being taught on the bottom. I saw one discover scuba (I guess) where her guide was literally trying to pick her crawling ass up of the floor. She was crawling on all fours towards a structure to see the fish. I was appalled. I bet 70% of the divers I saw were on the floor. It's not a quarry (where people get pissed if your on the bottom because you destroy the visibility). It's a habitat.

I dive with my wife for the most part, and while I have a long way to go, she has a longer way to go, but WE DO NOT TOUCH THE BOTTOM. Yesterday I was so proud of her as a diver (and myself I guess). We never touched the bottom. We're not perfect, but destroying the habitat of little creatures is unacceptable. Yo-yo'ing buoyancy is unacceptable.

I know I'm ranting, but is this the norm? I've never dove around numerous divers, but is this how most easily accessible places are? Please enlighten me on a different perspective. If this is how people are taught why would they ever change?

Now wonder people move on to tec. It's to get tf away from the masses?

If you think the diving is bad you should avoid driving a car at all costs.....

 

[Bob DBF]

So its really bad weighting that causes bad trim.

Bad weighting may cause you to have excess air in your BC (over weight) or floating to the surface (under weight). Buoyancy is tangentially affected by weighting, notably when your BC can no longer compensate for the improper weighting.

Bad trim is caused by not having the weight in the proper place(s).


Bob

 

[johndiver999]

I never understood the idea that a jacket BC tends towards bad trim.

I mean, if you're underwater (and not over-weighted), there should be very little air in the BC, so the bubble shouldn't affect your trim. So if its not the bubble, its not really the BC at issue

This is not a correct assumption. A diver may require over 20 or even 30 lbs of air (displacement) in their BC at depth. If this were to occur it could mean that the diver is deep with a thick wetsuit and may also have large tank(s) which could have 8 or 16 lbs of air in them at the start of the dive.

What is the source of this common misperception that overweighted equates to having air in BC at depth?

 

[JHumbert15]

So its really bad weighting that causes bad trim.

My weighting is fine. I'm assuming it to have been the location of weights because my fins (jets) are negative, and in a jacket style you only have so many options of where to put them, unless you are adding trim pockets. It has nothing to do with the weighting (solely the weighting I should say), it's the location.

- Jake

 

[Chavodel8en]

This is not a correct assumption. A diver may require over 20 or even 30 lbs of air (displacement) in their BC at depth. If this were to occur it could mean that the diver is deep with a thick wetsuit and may also have large tank(s) which could have 8 or 16 lbs of air in them at the start of the dive.

What is the source of this common misperception that overweighted equates to having air in BC at depth?

The scenario posed by the OP was overweighted recreational vacation divers with horrible trim and the question posed was what is causing "Horrible Divers Everywhere"? One "charge" leveled was that the bad trim in these vacation divers is caused by jacket BCs. We're not talking about experienced divers in doubles. Perhaps I should have clarified that I was addressing the scenario posed by the OP, and that I wouldn't be bringing up situations that aren't really relevant to the discussion.

So I will clarify, if a recreational vacation diver has alot of lift in their BC at depth, they are most likely overweighted, and this is a significant cause of their bad trim (as opposed to the type of BC they are using). Not a slight on experienced divers in a thick suit and/or diving doubles, who I don't think we'd find at Blue Heron Bridge in that configuration anyways.

 

[Chavodel8en]

Bad weighting may cause you to have excess air in your BC (over weight) or floating to the surface (under weight). Buoyancy is tangentially affected by weighting, notably when your BC can no longer compensate for the improper weighting.

Bad trim is caused by not having the weight in the proper place(s).

Bob

My weighting is fine. I'm assuming it to have been the location of weights because my fins (jets) are negative, and in a jacket style you only have so many options of where to put them, unless you are adding trim pockets. It has nothing to do with the weighting (solely the weighting I should say), it's the location.

- Jake

I consider bad location as part of "bad weighting," (my bad on the semantics) and as both of you point out, its probably the most important part.

Every jacket BC Ive seen nowadays has trim pockets - do they even make them w/o anymore? If it didn't, well then, someone would need to do the same thing they do with a BPW when trim weight is needed - add a tank weight or some kind of trim weight.

There are lots of cons with jacket BCs, but "they cause bad trim" is not one of them, not if the weight is in the right place.

 

[Bob DBF]

I consider bad location as part of "bad weighting," (my bad on the semantics) and as both of you point out, its probably the most important part.

It's just my preference to seperate weighting, buoyancy, and trim as much as practical, so that it can be easier to understand how to address each issue, and that proper trim and buoyancy control does not automatically mean one is weighted properly.

There are lots of cons with jacket BCs, but "they cause bad trim" is not one of them, not if the weight is in the right place.

Agree completely.


Bob

 

[ScubaWithTurk]

Bad trim is caused by not having the weight in the proper place(s).


Bob

This is the most accurate thing stated. It is based on the bodies fulcrum and where we place weights in relation to that begins to determine proper trim.