Which sidemount to get?

[hudson]

I cannot dive my 108s wet. I don't have enough lift in my 50lb wing, and my wetsuit is an 8/6 and only used for one summer season.

Rob, I assume the problem was at depth (recall what depth before the wing was insufficient?) - any problem floating comfortably on the surface? No stages involved, right? Nomad wing?

I think dive rite rates their wings by theoretical volume in salt water, where as companies like Halcyon and DSS tend to rate them by real world capacity. Maybe I'm wrong, but my nomad wing doesn't have anywhere near the volume that my 55lb Halcyon does, not much more than my 30lb oxycheq actually...

I don't know about Halcyon, but yeah, Tobin said DSS rates wings assembled, Oxycheq has stated their free lift is more than rated (32lbs for a Mach V 30lbs) so the 30lbs should be accurate with the wing on an Oxycheq backplate with a single tank. Somebody did test it on a DSS backplate and got only 27lbs. There is also a mention of a 40lbs rated wing delivering only 32lbs.

Hmm.. I think I'm gonna test the Nomad now. Update: Got about 40lbs with the bungees relaxed, but I didn't manage to get all the air out (it was sloshing around a little), so it's probably a bit more. I have a 50lbs wing.

 

[SangP]

The most ideal solution for steel tanks probably does not involve a butt-plate, but rather lowered wing/"hip-strap" and the shortest possible connection to the waist D-rings, metal-on-metal carabiners - that way they may ride at an acceptable height, and you'd have great trim.

That should work for cave, but my understanding is the line-trap potential is much higher in wrecks.

As an aside, friend of mine has tested the Profile with a 30lbs wing and dual steel tanks and didn't find the lift sufficient on the surface. 35-40lbs would probably work better.

The lower hip strap and attachment points are one of the reasons why I think the safety harness setups are better suited for sm diving than the soft packs.

Now if you want even lower attachment points then we're talking about modifying a rock climbing harness for sm diving.

Another alternative would be tank cam bands with special self locking hinges attachments that allow a tank to be attached lower but still retain proper position regardless of weight or lack of.

With a rock climbing type harness you can attach tanks a good 6" or more lower that even at the hips by putting a couple of D rings/retainers around the leg straps.

or

Something else to think about when I'm designing another harness.

Amen. Monkey-see, monkey-do all of the soft-plate ones. Multi-piece harness that's a bitch to replace? Check. Quad shoulder d-rings? Check. Chest strap? Check. Back pad? Check. Shoulder pads? Check. Crappy plastic QR buckles? Check. Ugh.

Well, some of the stuff is pretty useful. When using a sm harness and you need to rig the waist straps lower to the hips the shoulder harness does get a bit loose n a chest strap really helps especially as you can also hook up the power inflator just within reach. Strap pads also help reduce the pain of carrying multiple tanks. What I was commenting on some harness designs are the lack of stability of some load bearing components.

The current sm harness designs are just a modification of bm with the exception of the armadillo n razor.

What I hope to see is a dedicated sm system that has the best of the rock climbing and safety harness and proper sm wings.

SangP

 

[Dive-aholic]

Rob, I assume the problem was at depth (recall what depth before the wing was insufficient?) - any problem floating comfortably on the surface? No stages involved, right? Nomad wing?

You're assuming incorrectly. With the wing fully inflated to the point of the OPV opening, I still have to kick to keep my head above the surface. At 10 ffw, I can't trim out horizontally. So, I don't dive anything bigger than 95s in my 8/6 wet suit. No stages, original Nomad (50lb rated).

 

[SangP]

You're assuming incorrectly. With the wing fully inflated to the point of the OPV opening, I still have to kick to keep my head above the surface. At 10 ffw, I can't trim out horizontally. So, I don't dive anything bigger than 95s in my 8/6 wet suit. No stages, original Nomad (50lb rated).

Hi Rob,

If that's the case, what is a suitable sized wing for multiple ss tanks and stages?

Do you also think that having attachment points lower around the upper part of the Femur bone be a good idea?

SangP

 

[SuPrBuGmAn]

Attachment points on the femur are gonna make frog kicking clumsy.

60#s seems to be good for steel tanks and multiple stages.

 

[SangP]

Good point SuPrBuGmAn although, I was thinking of it being further behind near the butt.

We mostly use alu tanks here in Asia and unless the tanks are weighted down they float up at the butt when they get dry so, is there another solution for lower d rings attachment points?

SangP

 

[SuPrBuGmAn]

When I use AL80s or LP72s(which get butt light), I hook them on waist Drings(further out under me) to keep them from floating up. I don't use those attachment points when they're full(full I just use the buttplate), just when they start getting light.

 

[SangP]

That's what I do too but I was hoping for a all in one solution where I don't have to keep swapping attachment points during the dive.

I'm not a real fan of the butt plate but I suppose that if it ain't broke don't fix it .

SangP

 

[Jax]

:huh: I'd swear I saw a Hollis sidemount discussion in this thread, but can't find it.

Has anyone checked out the Hollis sidemount rig? My LDS is beginning to carry Hollis . . I promised I would look into it.

 

[Dive-aholic]

Hi Rob,

If that's the case, what is a suitable sized wing for multiple ss tanks and stages?

Do you also think that having attachment points lower around the upper part of the Femur bone be a good idea?

SangP

My Nomad works just fine, but I dive dry. I wouldn't even consider diving large steels wet. I have no problem adding a stage when diving 95s wet. Two stages wouldn't work...mainly because if I'm going to stay down that long, I need to be dry to stay warm enough!

The butt plate positions the rails along the upper part of the femur already.

I'd swear I saw a Hollis sidemount discussion in this thread, but can't find it.

Has anyone checked out the Hollis sidemount rig? My LDS is beginning to carry Hollis . . I promised I would look into it.

Jax, I've only seen the Hollis online. It looks very similar to the Nomad.

The differences -

The harness and butt plate are one piece. I like the modularity of the Nomad. My butt plate will need to be replaced before my harness. With the Hollis, you would have to replace the entire thing. More money than I want to spend.

The butt plate looks like it's positioned a little too high...or the wing is a little too long. This is going to force the cylinders to either be too high or the diver to have to use a much longer static cord on the cam band making the cylinders less stable.

The harness attachment point appears to be along the back. This is a common issue I have seen in other harnesses. The Dive Rite harness allows the diver to adjust where the shoulder harness attaches to the waist strap. Personally, I like mine to come almost straight down. This makes the harness more comfortable for me and also allows me to attach my back up lights to the shoulder harnesses without having them positioned between the cylinders and my body.


Again, I have not seen a Hollis SMS100 in person and probably won't until DEMA in November. If I do, I will try to get one in the water, but the first difference is a big one for me, especially considering how abusive I can be with my gear. The last difference is also a major point for me, however, some people may like the harness routed this way better. There's nothing wrong with it, it just doesn't work for me. I've had students with various sidemount systems where it also works for them. The majority of my students do end up in modified Nomads, though.