New rEvo BOV

[Brad_Horn]

If designed for the Horizon, max depth 40 m, essentially no or very little deco, direct trip back to the surface type of bailout, you can't expect the same performance as for a unit designed for tek diving. And the injection moulded design fits the bill of a cheap(er) product for the masses (remember, this is part of the Horizon which is sold for about half the price of a rEvo, AFAIU).

While the ALVBOV has been designed to support significantly deeper diving than 40m; having been tested as quite safe for use to 350m. It also is injection molded and I’d argue that whilst most rebreather divers are use to seeing delrin machined BOVs, which are cheap to one off for prototype purposes, injection molding doesn’t equal cheaper. Until you sell enough to breakeven but it does offer a better product.

As a positive the sunk cost investment by Mares in the tooling means they intend to produce quite a number of identical BOVs.
As a negative, unless it is found to fail CE testing, you’re not going to see any improvements in WOB. And from the sounds of things they have no intention of actually testing its WOB. As the cost of the tooling is too high to make it economically feasible to redo. Which is why OSEL doesn’t supply a left to right gas flow option (ALVBOV is fixed right to left as required for CE) as the market simply isn’t there to justify the cost. The initial prototypes of the ALVBOV were 3D printed and went through many many variants to get the gas flow right. In addition to the flapper valve trials in regards to the CO2 bypass link above.

 

[rjack321]

Whilst breathing off an independent OC gas supply, try going for a dive on your rebreather down to 10m, with the IP gas supply to the BOV isolated!
You might be unpleasantly surprised what the diaphragm looks like afterwards……

Whilst folk don’t plan to descend with their bailout isolated. It does happen.

Try again with a pdf this time?

The AGA type dual inhale-exhaust diaphragm allows a disconnected shrimp to flood on the OC side - it does not invert the diaphragm.

 

[uwxplorer]

Try again with a pdf this time?

The AGA type dual inhale-exhaust diaphragm allows a disconnected shrimp to flood on the OC side - it does not invert the diaphragm.

Which is why a genuine review by an actual diver of the thing is so valuable (including the background info on the company's lack of official statement)...

 

[rjack321]

Which is why a genuine review by an actual diver of the thing is so valuable (including the background info on the company's lack of official statement)...

Oh I fully agree with you!
I didn't even know there was a new BOV out there.

 

[Peter69_56]

We are in our newbness together.

So, my understanding is that a BCD whip will not flow enough gas to use for OC breathing at depth. That is, for example, why all Air2 (Safe Second - BCD inflators that are also an OC reg) have non-standard nipples on them and require special LP inflator hoses to be hooked to them. They use a nipple that is bigger than a standard BCD inflator, so that they can flow sufficient volume of gas.

I think that is why people use QC6 fittings. It will flow enough volume of gas to feed an OC reg at depth.

A BCD whip is fine, however, to use for inflating a drysuit or wing or plumbing offboard gas into the loop.

But with the REVO, unless you have to get off the loop, just plug in any inflator hose into the MAV block and stay on the breather. On all my bail/deco tanks I have a secondary reg (good for me and other divers), and an LP hose so I can plug any tank into my breather if required. Heaps of flexibility, backup for other divers, and bail out for me. My BOV has a QD but only into my bottom gas.

Works for me

 

[Peter69_56]

You can easily get a LPI male fitting with a one way valve.

If you are using a revo mav you do not want to hook up alternate O2 to that - it will blow tiny drops of water into your orifice and solenoid. You need to put in a splitter and hook up your offboard gas (whether dil or O2) to the dil side.

I am a little confused here about getting water into the solenoid? Are you suggesting to hook the offboard O2 to the onboard LP connector, thus water in the orifice will occur?

Why not if you need to, hook the O2 into the offboard LP connector and drive the unit manually?

 

[Peter69_56]

I have an ALVBOV, and am impressed with the design and workmanship, and of course the specifications, which is why I bought it.

However wordy Brad may be sometimes, either what he says is true or not. I was not aware of the vacuum problem with the diaphragm seal and wonder now how many other BOVs have this same problem as the rEVO/Mares does. It’s a very bad feature and could seriously hurt someone or at least delay you from diving if discovered beforehand.

This then begs the question, does everyone test the OC side of their BOV during predive? Does the BOV OC diaphragm on BOVs that do not have the right lip type seal, collapse every time you pull a negative test, or only if it is a very hard suck negative test?

Always test BOV OC predive. Part of my check list

 

[Peter69_56]

Is there a gag strap for the divesoft BOV, as thats the BOV I currently have?

 

[stuartv]

Is there a gag strap for the divesoft BOV, as thats the BOV I currently have?

I don't know. But, the rEvo gag strap fits onto the BOV just like any normal regulator mouthpiece. So, as long as the dimensions of the opening match up, the standard rEvo gag strap would probably work. Do you have either a standard rEvo one, or the standard rEvo DSV? If the Divesoft opening for the mouthpiece is the same size (or close) and design (as far as the single retention lip on the breathing orifice goes) as the stock Drager DSV opening, then the rEvo gag strap should work.

 

[Peter69_56]

The REVO gag strap/mouthpiece is bigger than the Divesoft BOV fitting (from memory as I am currently not home). A standard reg mouthpiece fits the Divesoft