Razor 2.0 or 2.1 or SMS75

[djcheburashka]

Victor - thank you for that, I think this is a very helpful exercise.

It's a pretty good library of the ways that trimming out a tank on the Razor can go wrong.

What would suggest to fix the various issues?

For #3 I think he needs to be clipping the AL80s onto the forward d-ring earlier in the dive. My experience has been that, in salt, Al80s belong on the front d-ring by 2500 or 2000 psi.

I'm not sure what to do, though, with the Razor's configuration, about what's going on near the valves. The forward configuration on a Razor is like a mystery wrapped in an enigma buried in a puzzle.

I'm also not sure what he should change to get the tank back into its proper place, or to trim-out his steel tanks. One of the hardest things about configuring the Razor is finding a configuration that works for both steel and aluminum.

If you think about the geometry and the kinematics -- since the front is supported by bungee, the front of a steel tank is going to hang lower than the front of an aluminum tank on the Razor. And even if one tank of a particular weight and length trims out fine, a tank that's otherwise identical but has a larger diameter will hang at an angle. This is not a small problem -- back to that whole thing about Right Triangles, since the bolt-snap is in the middle of the tank, the position of the rear of the tank will be twice as far off-trim as the position of the boltsnap.

I suspect he may need to move the chest d-rings up and increase the tension on the sidemount bungee while choking-up on the position of the sm bolt-snap on the tank. His only other option, it seems to me, would be to lower the rear d-ring, but then the whole tank is underneath him.

***

One of the things that struck me, I took a very close look at the Steve Martin pictures, and a couple things stood out. The first is that he's quite a bit taller than I am. His boltsnaps are much lower on the tank than mine. That makes a huge difference -- the difficulty of getting tanks level in the Razor is exponentially proportional to how much the tank extends beyond the waist strap.

The second is, I suspect he's just thicker than I am. I'm a 38" chest. If he's a 42", then he's got an inch or so of radius on me. (Don't you just love math?) The reason this matters is the way he clips the stages. He has them clipped on so that there's tension on a boltsnap between the stage valve and chest d-ring, and the tank is also running alongside and touching the back gas. The only thing keeping the two regulators apart is the thickness of the bottles. Well, if I try to do that, with an inch less radius, it just isn't going to happen. There's no "give" in his configuration. On my body, the parts aren't going to fit together. Which is, basically, what I've experienced with four bottles, and why I've ended-up turning the stages around so the regulator is on the bottom (which is obviously a problematic configuration).

 

[Razorista]

Victor, I have been saying the way this discussion is going is getting on my nerves for some time now.

I appreciate you trying to show something, but I do not think the axes you drew into the pictures reflect the situation well. A few degrees of bias change the overall picture to something not reflecting reality very good.

Sometimes you drew the body axis from neck to knee (i am no cave diver, I am allowed to move those ;-)), sometimes more from breastbone to knee.
I also do not think you got the perspective right completely.
Most of all I do not see why the perfectly lying single steel tank in the last picture should be anything to criticize, especially doing that kind of movement with it.

You even see me flip over several times without the tanks moving around much and them keeping a suitably diveable position - which I do not think would be be possible with tanks misaligned to much?

As I already stated:
I my opinion it's overall results that count. If tanks are not lying perfectly sometimes there is still room for improvement (as I said several times).
However, I do not think it is bad at all in that particular video (less ideal footage then I would like, but only that), because the results seem satisfactory to me.

 

[victorzamora]

In the last picture, you can't see where your tanks are trimming to. However, the VERY valid assumption is that since your valves are well infront and well below where they need to be, your tails will be too high. Period. It's geometry. In the second to last (penultimate) picture, your tanks are FINALLY flat but it's far too low.

But seriously, the overall point I was trying to make is that your tanks are FAR out of line. I showed that graphically......from every clip of a video you claimed to show good technique. Whether or not my lines are off by a degree or two, and whether or not I have perfect consistency in my drawings shouldn't matter. I made those sketches at night, in bed, while tired. They're not perfect, but they're close enough to show how far out of line you are. Also, flat is supposed to follow your torso.....so any line I drew to your breastplate REDUCES how bad it is, make you seem better.

About your rolling. Congratulations, your tanks barely moved. How often are you going to be diving upside down? Also, and more importantly, they're still in bad trim. They start in bad trim when you're upright, and they stay in bad trim. My wife, who doesn't sidemount (yet), asked who the beginner was that I was trying to help out. Look, if that works for you in your 10m deep quarry dives.....then enjoy it. But Daniel, seriously, stop giving advice as if you're an expert. You're far from it, and you're too lazy and complacent to fix it and learn and progress. No matter how much you dive, unless your attitude changes, you'll always be a beginner and mediocre.

I know that all of that sounded rude, again, but I'm seriously not trying to be. I'm saying it from as factual and scientific a standpoint as I can. You're German, you should get that

 

[Razorista]

@victorzamora
I do not dislike the way you are handling this that much.
I just think you are totally wrong!!

btw: I am still waiting for any footage to show you or anyone else here.
I ignore the one pic showing someone in the water because the poster was not that happy with it either (and it really shows someone looking like a beginner trying to keep a not so stable trim for the shot).
If you criticize this vehemently you should at least show you can do it better if you choose the pictures for that (I did not choose my best pictures and do not like to do so, I prefer to be honest).

The way you are writing like you knew some unchangeable sidemount rules sounds to me like you still do not know half as much as you seem convinced to know, sorry.

Tank-trim does not have any purpose or virtue in itself.
Fanaticism will no help you realizing that some tanks allow very streamlined movement for example if not perfectly positioned.

As I repeatedly stated I have to take the video I can get, if I want any of myself.
Those are tests, demonstrations and sometimes just things for the group to discuss in debriefing.
But I liked the overall video after cutting, so I simply put it up on youtube (for family and close friends mostly).

You can get angry all you like: It works!
Everywhere and on a level most of the very self assured technical divers here could not match (though I never do technical dives at all - no fun involved for me).
I do not know about you Americans, but here I do not meet divers on the level you seem to have as constant companions - not even close.

How often are you going to be diving upside down?

Constantly. I like to watch the surface and ceilings from below for example.
In the first scene in the video I am watching a diving bird and turning with it.
When I am alone I often just hang under trees for most of the dive and only move from one interessting spot to the other and wait there for something to happen (or not). I nearly went to sleep once but was woken by other divers running me over, so I cannot get that relaxed since that happened anymore, but I will get there again.

Also, and more importantly, they're still in bad trim.

What difference does it make if you do not like the tank-trim? It works that way very well.

They start in bad trim when you're upright, and they stay in bad trim.

What makes them trimmed badly?
Your ideas of bad trim?

They do not pull me up or down, they fit through any restriction, I can move with them freely in any position and they do not encumber me.
Actually that would be the definition for 'trim' with all the reasons for wanting it to be 'good' included.

But who defined what is good and bad?

My wife, who doesn't sidemount (yet), asked who the beginner was that I was trying to help out.

So, even those who know nothing know more than I do, is that the idea you want to hint at?
Perhaps you are wrong there again?

Look, if that works for you in your 10m deep quarry dives.....then enjoy it.

I do enjoy it.
But as it also works anywhere else for me...
45 meters Egypt, 30 Meters at 0 degree surface temp, salt- and feshwater, in caves, caverns and wrecks.
I admit it also works well when I have time to use the camera for less important things than documenting what I saw on the dive for later, even at 10 meters (that video was is made in a lake where 10 meters require a shovel).

But Daniel, seriously, stop giving advice as if you're an expert.

Victor, seriously, you should not try to decide what advice others give on a forum.
I am doing this for next to four years now, other people with much less experience give a lot of good and bad advice here and other places.
I was very quiet first, than I started to get active on forums. I get flamed a lot, but sadly I am later proven to be right most of the time.

I got more active here because nearly any post I wrote got 'liked' by someone, even you at least once.
Now you do not like me personally all of a sudden, but that is not a problem I am concerned with, I did not see I gave you any reason or justification for this. From my point of view you prove not to know any better.

I hate the attitude of some that they can tell others what they have to do for any reason and will not tolerate it or cooperate in that ever.
Especially I people think one or two weekends getting certified as anything makes them superior to others in some mystic way.

You're far from it, and you're too lazy and complacent to fix it and learn and progress. No matter how much you dive, unless your attitude changes, you'll always be a beginner and mediocre.

I will remember that the next time some sidemount instructor asks me for advice after the dive again ;-)

I may seem like a typical case. After reaching the personal goal comes complacency. I am not, I just do not know to fear criticism anymore.

I am trying to stop giving advice in person actually, because outside the internet it is not much different.
People come to you, cannot stop showing admiration even if not required or liked or all, hang on you like leeches for a few month and as soon as they think they know everything they act like they knew everything long before the one they leeched the info and skills from in the first place.
I sometimes think the lower the level of the tech or instructor card used as a reason for superiority the more the owners abilities and perspectives have been damaged by it...

I know that all of that sounded rude, ...

It's not the rudeness that is bothering me.
It is the general attitude of harassing people giving advice on a forum just because you do not like their opinions or do not respect those or the people themselves.

 

[djcheburashka]

Victor: can we just ignore Razorista? He's never going to stop as long as we respond to him. He's trolling. Ignore him and he'll go away.

Meanwhile you've started a great conversation about trimming out tanks.

Accepting that you have indeed got the correct goal, how would you change the configuration of the gear to achieve that goal?

 

[Razorista]

Ignore him and he'll go away.

Not the first time you are wrong today.

I am not trolling, I am the one having to defend himself here.
It is easy to provoke a discussion like this to damage others as you have done - that makes you the one trolling in my book.

btw: you are the one looking unable to control the 40cft in his picture, so tell me: who or what entitled you to this?
Yeah, I know, 'all the good ones are on the other iPad'...

 

[victorzamora]

Victor: can we just ignore Razorista? He's never going to stop as long as we respond to him. He's trolling. Ignore him and he'll go away.

Meanwhile you've started a great conversation about trimming out tanks.

Accepting that you have indeed got the correct goal, how would you change the configuration of the gear to achieve that goal?

I'll try my hardest to ignore him. But there's only so much I can do to contain myself around that much ignorance (please note: I'm using this in the true meaning, not its current connotation). If sidemount tank trim didn't matter, Steve Bogaerts wouldn't be charging what he's charging for gear and training, and everyone would be "sidemounting" two stages clipped in front of a BPW with a second backplate sandwiching the wing in place.

So, the goal with sidemount tank trim is to have the tanks in line with and parallel to your body. If you're in proper diving posture, you can draw a line from your shoulders to your knees and see that your back arches down a little bit. This is proper posture (which is very hard for me to achieve due to spinal cord damage). You want your tanks parallel to that line in order to reduce drag and reduce your cross section for restrictions. Even in OW, you want drag reduction for ease of swimming and reducing your cross-section for scooters or current. Tucking your valves up underneath your armpits (instead of below and/or in front of) gives you the most drag reduction AND protection for your dive gear. This is, unequivocally, the ultimate goal in SM. It gives you the most protection and the least amount of drag. Riding with your tanks at an angle causes nothing but increased drag and decreased protection. Plus, you look like a typical weekend-class instructor instead of the experts you should want to emulate.

So, to make that setup more inline with achieving proper tank trim, I'd start with shortening my crotch strap to lower my waist band a couple of inches. I'd shorten the bungee quite a bit, and I'd move the bungee towards my feet if shortening the crotch strap didn't accomplish that. This would be a great start. Shortening the crotch strap would lower the waist band to where the Razor is supposed to be worn (much lower than BPW waist strap location). Much more importantly than "supposed to" is that it does to your tanks.....which is this would bring the tanks towards your knees and would get the valves out from in front of your chest. Lowering the bungees, if necessary, would keep the bungees pulling straight up on the valves instead of forwards. Shortening the bungees would allow the valves to ride higher, inline with where they need to be.

I say this is all a good start due to not being able to be 100% sure what those changes will do. It might turn out that the bottom leash length needs to be lengthened or shortened and that the waist d-rings need moving. Like I said, I'm not sure if it'll be perfect.....but it would be a whole lot closer. One other thing to mention is I might change that setup to a Stealth-type sliding d-ring to remove waist d-ring position as a variable and keep the tank in constantly perfect trim.

 

[shoredivr]

Enjoyed the tank/body axis series, and the geometry of tank trim information.

All this is making me think that for steels in cold water, like up here, the SMS75 would be my choice. The old skool Nomad is still serving me, but next SM rig is likely Hollis.

 

[victorzamora]

The SMS75 is absolutely perfect for big steels and cold water. With a little know-how and some brain power, you can dive AL80s and neutral steels as well in an SMS75 as in a Razor....but you won't have to worry about the beach ball of death grabbing you.....especially if you start doing big dives.

 

[djcheburashka]

Victor: ok, but...

At the bungee, I have four factors I can adjust. I can change the bungee length. I can change it's tension. Where it runs behind me, I can move that up or down my spine. And I can move the chest d rings up and down. What do you mean by "lower the bungees?"

I do disagree with you about the waist strap. As long as the position of the waist strap matches the position of the bolt snap on the tank, that's ok. Of course having the strap higher up increases the effect of a misalignment.

I did change the front d-rings to the stealth adjustable ones. I don't think changing the rear is feasible because that's where the tanks are attached on entry. Even the stealth people say not to attach steel tanks to those things out of the water.

---------- Post added August 12th, 2014 at 02:34 PM ----------

Oh-as for leashes, unless he's doing something radically unusual the leash length should be zero. Picture attached.