Evo mod to a backplate

H20Sensei

I rigged up my Evo onto a a Dive Rite BP and Transplate Harness. I made the counterlung straps out of the crotch straps provided with the unit. I dove it today and it felt great. Much better than the AP harness.

I have a stoopid question.... I know that for OC, the SS backplate helps with weight and trim. Is this the main reason for using it on an Evo, or is it just for rigidity?

The reason I ask, is that I'm thinking that for travel, the aluminum plate might be better, but will not help with the weight/trim. It will still offer the rigidity, with a fraction of the weight.

Any thoughts on this?

jhaaja

With an alu backplate you can use a weight that fits the slot in the backplate. This will give you the weight needed and also help to obtain good trim.

JH

caveseeker7

Obviously an alu backplate has less negative bouyancy that one made from steel, but may still notice an advantage over the stock webbing as that usually has more ingerent bouyancy than either backplate.

When I switched my OC gear from a Zeagle Ranger to a Dive Rite aluminum backplate and harness I saved a couple of lbs of weight on the surface, yet needed 3 lbs less lead uw. Add the stability and easy maintainance and it's a win/win situation.

The Ranger fits my Sport Kiss, but I never bothered diving it.

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Stefan



"Political Correctness is a doctrine, fostered by a delusional, illogical minority,
and rabidly promoted by an unscrupulous mainstream media,
which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.!"

camerone

The main reason for using it is that the stock harness sucks. It's got to be the most poorly designed BC harness on the planet, short of tying the rig on with binder's twine, and I can't help but wonder "what the hell was AP Valves thinking?!"

Seriously, though, it's really about the poor placement of the d-rings on the harness, shoddy crotch straps/chest straps, and the fact that no matter what you do, the darn rings always get trapped underneath the counterlungs. Couple that with the fact that the back of your bottles is actually hanging off the wing, not the webbing, and there's good reason to put a standard harness on the unit.

I can't actually think why anyone thought it was a good idea to hang weight off the _wing_ for the hip d-ring, instead of the harness.

I put a DSS SS plate on my Evo, along with the under counterlung D-rings that stick out, the Evo-plate-adapters, and the counterlung tiedown straps from DSS. It's made it a LOT better. My canister light actually sits on the hip webbing without crazy contortions to pull enough webbing free to thread it, I can reach my d-rings and clip things off, my backup lights lie where they belong, the crotch strap can actually pull stuff without slipping in the little fastex buckles, and the trim is a whole lot better with six pounds distributed across my back, instead of trying to wedge large weights in the cruddy shoulder pockets of the APV wing.

I also upgraded the wing to a 55 lb one from Oxycheq. The lift on the Evo wing (16 kg) is completely insufficient for deeper diving with large sling bottles, and they won't sell it with the larger, 22 kg wing. With the wing upgrade, I also got rid of the worthless AutoAir and put a standard inflator on there... easier, more reliable, and it sits close to my neck instead of dangling around on the dodgy hose they include with the unit.

My only regret is not doing it sooner; it took me 18 months of debating it while diving the unit to actually go ahead and put the parts on there. My mistake was not doing it on day one.

I love my Evo and wouldn't give it up, but it just cheeses me off to pay the price they charge for the unit and have to spend yet another $600 to put a decent harness and lift system on it.

H20Sensei

I looked at the DSS backplate adapter on their website and couldn't figure out it's purpose. I called DSS today and the person who answered the phone had less of a clue than I did. He literally said: "If you can't figure it out from looking at it, I can't really help you". That instilled great confidence in the product for me and made me realize how ignorant I am.

Can anyone enlighten me on it's purpose?

I attached an aluminum backplate to the Evo with the screws provided (without a problem) and it feels great. I set it up with a Dive Rite harness, crotch strap and small weight pockets, as well as the pocket for their new handheld LED. I also made counterlung straps out of the AP crotch straps. So far, so good.

I like the idea of the aftermarket D-rings and counterlung brackets, but I'm affraid to ask....

jhaaja

I use just normal hogartian harness without any under the counterlung d-rings. My harness is not so tight around the shoulders so it is easy to pull the d-ring behind the lung. Also the lungs are not so tightly strapped to the waist strap.

JH

caveseeker7

You should have asked for Tobin (cool_hardwardware52 here at RBW), it's his shop and makes them. Is a rather large shop and dive gear is just part of it. Rebreather accessories probably a tiny part, so not having someone being able to answer your questions can happen. I've seen the adapters on PRISM and Evolution CCR, both well fitting and very solid.

Am not sure why AP units can do with an adapter, I believe it has to do with the uneven shape of the case. I remember seeing pics of people cutting into backplates to mount them to their cases, so a WAG would be the adapter bridges whatever is in (or out) of the way. Also, they should distribute the load a bit from a two screws/holes in the case to four of them.

Maybe Tobin will see this post and chime in, otherwise send him a PM.

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Cheers
Stefan



"Political Correctness is a doctrine, fostered by a delusional, illogical minority,
and rabidly promoted by an unscrupulous mainstream media,
which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.!"

camerone

The adapter (for the Evo) is actually two pieces of metal, two bolts, and two Delrin thumb wheels. The flat piece sits on the outside of the plastic case, down by your lower back, the "U" shaped piece is the upper bolt holder.

The included bolts are longer than the stock APV ones. The metal adapters are threaded, so the bolts stay captive; if you were to just put generic bolts in place without the adapters, when you remove the backplate, the bolts would fall through into the Evo case.

The metal plates provide a uniform, flat, level surface for the backplate to rest against. It keeps it from being wobbly, which is what happens if you just bolt an unmodified backplate to the Rebreather shell. The shell itself is molded for the manifold, cylinders, etc, and it's not got the flat bits in the right location for a backplate to bolt and feel rigid, although it will work without the adapters, if you don't care. As was pointed out, they also distribute the stress across a wider bit of the backplate, with sturdy metal, instead of the flimsy ABS; when I had a Drager Dolphin, I machined something similar, myself, because the case was always cracking right around the mount points for bottles and such.

I really like the adapter, if only for the fact it holds the bolts captive and allows me to easily assemble Evo case + wing + counterlungs + plate, and remove the BP/Wing without having to remove the scrubber and disassemble the Rebreather to hold the bolts.

The under-lung D-rings are awesome; they're huge, and they're always right there. I can single-handed "Blind" clip lights on the harness again, while I almost always needed two hands with the APV harness.

The counterlung metal pieces that thread on the waist belt are gravy; sewing loops of webbing with fastex buckles would've worked just fine, or the bungees that some others use. On the other hand, they're cheap, convenient, and give it a much more "finished" appearance. Also, the one horrible problem I had with the APV crotch straps (held on by those clips and loops) were that the loops were always falling off the waist belt. I would always have to remember to clip it together when I got off the unit, lest I lose the part that secures the strap to the front of the belt. I didn't want to risk that for the counter lungs, so with the metal clips threaded on the stiff webbing, they're not going anywhere.

cramerdn

Same here. Anyone want to buy a pair of DSS counterlung D rings?



The Evo adapter plates work great and give you long enough screw extension to easily stack up the wing and backplate.

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cool_hardware52

I'm sorry I was unavailable to answer your call, that does occasionally happen. You were given the opportunity to leave your name and number, but declined to do so. I do return my calls.

Any specialty hardware for Rebreather's that I choose to produce is almost exclusively the result of parts friends of mine have asked me to make. If others want them great, if not oh well.

It is a bit unrealistic to expect any specialty suppliers to the Rebreather market to have a bank of application engineers waiting to take your call. The answer you were given was the truth, we don't BS people here, if the person answering the call doesn't have the information you request they are instructed to tell you exactly that.

If your current solution is meeting your needs why are you seeking another?

Why?



Tobin

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