Sidemount Suggestions - OMS Sidemount Adapter

[gextyr]

I plan to do Advanced Nitrox and Deco Procedures beginning early next year. I have spoken with my instructor, and he prefers to teach tec classes in conjunction with the sidemount class. Since I'm interested in learning about sidemount diving anyway, I'm leaning towards going that route. He has gear available for me to use, but I generally prefer to use my own gear. I have been investigating different options, and there seem to be a ton of good options ones out there (diverite, xdeep, hollis, hog, utd, halcyon, etc.) - but I'm really interested in trying out the OMS Sidemount adapter. The primary reason is so that I don't have to invest a lot in a dedicated sidemount BC until I've decided I like sidemount diving... but I also like the idea of diving with the gear I am already comfortable with. The instructor is very open to me choosing my own gear configuration, and the training agency isn't strict about it.

So, has anyone tried/used the OMS Sidemount adapter, and if so, do you have any feedback?

Also, I currently dive singles with an aluminum backplate, an 18lb Oxycheq wing, and a PST HP120. I was concerned that 18lb wouldn't be enough lift, but I am planning to use al80s (for now) and it seems like the overall buoyancy for a pair of al80s actually greater than the single PST HP120 I dive now. I even carry ~4lb of lead when diving a single 120, so I figure (correct me if I'm wrong) that even with an extra regulator, I shouldn't have to worry about having enough lift with that wing when diving with two sidemount 80s.

 

[tbone1004]

wing lift has very little to do with how much lead you wear or how big the tanks are, but has a LOT to do with how much wetsuit you are wearing because that is going to be a large contributor to the buoyancy changes that need to be compensated for.

The OMS adapter works fine if you are staying in open water and don't plan on going into restrictions and for $150 *have to get some sort of bungee system to work with it* it is fine for adapting to a sidemount rig.

Now, the 18lb wing is going to be further restricted by the adapter so you will get nowhere near the 18lbs that it says it has when unrestricted *The 18lb wing is VERY narrow and the oms adapter is probably within a couple of inches of the wing width*, and you may struggle with trim because it doesn't restrict enough of the top portion of the wings. If you had a 30lb or 40lb wing that would be a different scenario, but the 18lb wings are very tiny and while I haven't done it personally, I fear that it will restrict that wing far too much to be useful.

My recommendation is to use the instructors rigs if he is open to that, especially if he has a Katana. The preferred rigs on my list being the Halcyon Contour if you are over 6' tall and plan on diving steel tanks, and the Hollis Katana if you want to multiuse with aluminum. At $500 the Katana is a great deal and in my opinion the best rig on the market at the moment and the only one that I haven't had to make any serious modifications to. The only thing that this had done to it was change to a split crotch strap *for scootering, without a DPV the stock crotch strap is fine*, and the rails were replaced with bungee to hold a canister light and without the canister or dpv you can leave it 100% stock.

Here is a picture of me in one of the final prototypes in a 5mm wetsuit with PST HP120's. This is about 5 minutes into the first dive.

 

[DevonDiver]

I have used one. It's really for use with steel tanks and doesn't rig for aluminium well. Buttplates, independent bungees etc..

Its 'ok', but not great. To be honest, you need a bit of sidemount experience to get it rigged effectively.

As a 'sampler' it won't give you the full experience of a well conceived, well configured and dedicated sidemount rig.

 

[DevonDiver]

For the diving you describe, check our the Deco Sidemount.

New System - The Deco Sidemount

More than sufficient for 2x AL80.. and not much more than an OMS Adapter. I'll be testing one in-depth soon.

Regards buoyancy.... I use a Trim Pillow with 2kg lift when diving 2 AL80s. That's with a 3mm wetsuit and 4lbs of lead.

Submerged it'll support 2xAL80 and 2xAL40. Surface floatation is at eye level though..... but that's only 7-8 buoyancy in a tiny wing.

 

[gextyr]

tbone1004 - With this rig, I will be sticking to open water (no interest in caves, possibly limited wreck diving.) I live and mostly dive in FL, so from May-Oct it is rash guard only temps. For Nov-Dec/March-April, or diving in freshwater, I wear a 3mil. I generally go somewhere warmer if I want to dive Jan-Feb I appreciate the insight, especially regarding trim. I hadn't though about that too much. I'm not sure how much lift I'd lose sandwiching the wing like that... I'm almost tempted to buy one just to try it

DevonDiver - that is what I needed to hear. I'll probably just start out using my instructor's gear (he uses DiveRite Nomads.) Once I'm a little more confident in my abilities as a sidemount diver, I may look at the sidemount bladder you posted. It looks simple enough for lightweight sidemount diving!

 

[Remy B.]

my instructor takes the same approach when he teaches AN/DP, and I'm certainly happy to have taken that path

 

[DevonDiver]

For what it's worth.... the following blog link shows my efforts with an OMS adaptor. This was back when there weren't many options for dedicated sidemount rigs. I first put it together with a 30lb single-tank wing, then later with a 60lb doubles wing. That was my redundant sidemount rig for the deeper tech dives.

The newer OMS adapter... the recreational one.... should be a lot easier to configure. The 'tech' version of the adapter didn't work well with anything other than the OMS Tesseract wing... because of the 'loop over' protection at the top. It was a struggle to keep everything snug and streamlined.

Some Options for DIY Sidemount Rigs

 

[gextyr]

That's a good write-up. I have a few of those OxyCheq travellite backplates I have never used... maybe i'll hang on to them in case I ever need a setup like that.

If I do order an OMS Sidemount adapter, it'll be the rec version. Looking at my narrow 18lb wing, though, I'm pretty sure it will be completely covered by the adapter. That may not be a problem... but now I wish I could find one locally just to see how it all fits together.

 

[toby43]

If it was me, I would learn to dive the sidemount configuration first proficiently before attempting a tech diving course. It will take a while to get any sidemount rig dialled in, whatever they tell you. Otherwise do AN/DP on backmount. You will still need to learn the configuration but it will be quicker. Then I would try sidemount later if I thought it would be useful.