MK2

[evandroairton]

Hi there
Being thinking about using SP MK2 as onboard regs, with opv as an option for my travel setup on my inspo travel frame
Have seen some friends happily using them flawless even on 70 metres dives, and, as a easy service work horse looks good for this use, since twice i have apeks dst and ds4 seat failure during dives, and they are cheaper than poseidons with integrated opv.
My Ap's yellow box setup never vive me any trouble, but are tô dificult to change betwen units
Hás anyone tryed this setup? Any advice (maybe detune the IP on O2side?open to arguments and other opiniões
regards

 

[GF99/99]

I personally have never used MK2's (all my units have US4's or DS4's) but I do not see any issues with using an MK2 for that. I use to use was as an inflation reg and loved it. They should work great for dil/O2. As you mentioned just make sure you set the IP's accordable for your unit.

Remember rebreather first stages are barley doing any work compared to what a normal OC first stage would do. A lot of the cheaper lower performance lower option 1st stages work great as dil/o2 first stages. I have been using cheap Apeks US4's forever. Sometime you can pick these up used for around €70-80 and even new you can find online sales for around €110 in the EU (US is different). If I was down the SP rabbit hole I would for sure consider the MK2

Only other thing I can think of is the that the MK11 might make for better hose routing.

 

[rolanddiver]

I use SP MK2 on my rebreathers, but it only drives the orifice. It has been modified (made non-compensating). It is a very reliable first stage, but you have to keep in mind that it is non-balanced so IP changes slightly as tank pressure is getting lower and also you can't adjust the IP like on the diaphragm first stages. To drive the solenoid and MAV I use a SP MK11 on my smaller reb and MK17 on the other one and the O2 IP is set at 5 bars. SP MK11 is a very lightweight compact 1st stage. Just my two cents worth...

Very Respectfully

Roland

 

[rjack321]

I use mk2s on my Meg (with solenoid). They work great and about as reliable as can be. I have never heard of a HP seat failing in one (although it probably happens, certainly not at the rate sealed diaphragm seats tend to fail) I see no downsides at all. They are both at the normal-ish 140psi IP, not sure why you want to turn it down for an eCCR AP? You don't need big flow rates for onboard regs in a conventional onboard dil/o2 setup anyway.

 

[evandroairton]

I use mk2s on my Meg (with solenoid). They work great and about as reliable as can be. I have never heard of a HP seat failing in one (although it probably happens, certainly not at the rate sealed diaphragm seats tend to fail) I see no downsides at all. They are both at the normal-ish 140psi IP, not sure why you want to turn it down for an eCCR AP? You don't need big flow rates for onboard regs in a conventional onboard dil/o2 setup anyway.

Yes, i've made a mistake, both my units solenoids can handle 140, according to the specs

 

[rsingler]

Why would you want that current draw? You're forcing that battery to work much harder to pull the solenoid open. Battery life is less than 2/3 of what it would be at 95psi.
As voltage drops a bit near the end of battery life, it may not open at all.

 

[evandroairton]

Indeed, o see your point, keeping the ip on the 7 bar range would make Sense on saving batteries, specially disposabe ones on remote trips

 

[evandroairton]

Just for notice
Have built two MK2 evo as onboard regs for my travel setup today
Removed the plastic schrim from the o2 side (7.5-8 bar ip achived), and tested dry with both the AV1 and vision heads and both are ok.
Maybe a swivel for more streamline but It seens alright.
Fewer moving parts, less trouble.
ASAP if you wish, will put impressions.
Afaik, as on a rb the effort isn't like a normal oc reg, so i can't anticipate any major problem on depth
Regards