scrane
Contributor
How about ease of breathing? Will cracking pressure be consistent with a balanced second stage with a tank pressure from 3,000-500 psi?
What is the maximum operating capability of a Scubapro MK2?: Your opinion
- Thread starter Eric Sedletzky
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I really didn’t want to answer this because it makes me confront my choices in first stages.
I someone suited you up with you favorite second stage but didn’t let you see the first you would be unlikely to have and idea what first stage was attached.
my first stage choices really come down to hose routing and ease of servicing (to get the hose routing because nothing is easier than a mk2 to service)
I don’t like rotating turrets but I do like the L over the - (90° over the straight 180°)
Eric you need to stop with these posts that make us confront our silliness!
I someone suited you up with you favorite second stage but didn’t let you see the first you would be unlikely to have and idea what first stage was attached.
my first stage choices really come down to hose routing and ease of servicing (to get the hose routing because nothing is easier than a mk2 to service)
I don’t like rotating turrets but I do like the L over the - (90° over the straight 180°)
Eric you need to stop with these posts that make us confront our silliness!
johndiver999
Contributor
The MK2 with a DIN, and a first stage swivel is a nice little bit of kit.....
Someone mentioned cold water concerns...
I use the MK2 without any concerns as my emergency bottle for Ice Diving. I'd think the EVO with the coated spring would make it even better!
Might have to watch the used market for one...
I use the MK2 without any concerns as my emergency bottle for Ice Diving. I'd think the EVO with the coated spring would make it even better!
Might have to watch the used market for one...
It is a "normal" liter, at 0°C, 1 bar. These data are on the Scubapro catalog...
As a standard AL80 tank contains roughly 2200 liters, it means that connecting a MK2 and without any second stage the tank is emptied in less than one minute...
Such a massive air flow if far beyond anything you could even need for breathing, at any depth.
Of course, if you use the tank for filling a lift bag, or feeding a "sorbona", then you could possibly need the higher air flow provided by the top-range regulators.
OP
Eric Sedletzky
Contributor
So the reason I bring this up is because a while ago there was a thread about regs and an unbalanced MK2 came up in the discussion. Someone swooped in with a remark that an unbalanced MK2 is only good for stage bottles or pony bottles and shouldn’t be used as a primary reg because they do not provide enough flow.
At max recreational depths of 130’ at tank pressures acceptable at that depth, not almost out of air (nobody should be that deep and almost out of air), I say hogwash.
Part of my gripe is that new divers reading this forum who are just basic recreational divers might overlook the MK2 based on erroneous information they read here and miss out on a reg with great performance, simplicity, and durability, for what they are doing.
When I first bought my regs the shop steered me away from a MK2 and sold me a MK20 instead telling me the MK2 was not going to be good enough and I needed better. Well of course now it’s obvious that they were milking me for money, but I could have saved a few bucks and still had a great reg for the diving I was doing.
I’m just trying to blow up a myth about MK2’s not being adequate for new divers looking to get a first reg set. They are great regs at a great value.
For basic recreational dives I think the whole “you must have a balanced 1st stage” thing is a little bit drama queen and overblown.
I dive in 50 degree average ocean waters and freeze up was never mentioned as a thing, I know now it isn’t a thing and never was a thing with scubapro piston regs even down to sea water in the mid 40’s. However, flow through pistons like a MK20 are theoretically more prone to freeze up than a flow by unbalanced piston like a MK2, no?
Question for tech divers: thought experiment.
Would you theoretically use a set of MK2’s on your back mount doubles with confidence? ….with any 2nd stage of your choice, it doesn’t have to be a Scubapro.
At max recreational depths of 130’ at tank pressures acceptable at that depth, not almost out of air (nobody should be that deep and almost out of air), I say hogwash.
Part of my gripe is that new divers reading this forum who are just basic recreational divers might overlook the MK2 based on erroneous information they read here and miss out on a reg with great performance, simplicity, and durability, for what they are doing.
When I first bought my regs the shop steered me away from a MK2 and sold me a MK20 instead telling me the MK2 was not going to be good enough and I needed better. Well of course now it’s obvious that they were milking me for money, but I could have saved a few bucks and still had a great reg for the diving I was doing.
I’m just trying to blow up a myth about MK2’s not being adequate for new divers looking to get a first reg set. They are great regs at a great value.
For basic recreational dives I think the whole “you must have a balanced 1st stage” thing is a little bit drama queen and overblown.
I dive in 50 degree average ocean waters and freeze up was never mentioned as a thing, I know now it isn’t a thing and never was a thing with scubapro piston regs even down to sea water in the mid 40’s. However, flow through pistons like a MK20 are theoretically more prone to freeze up than a flow by unbalanced piston like a MK2, no?
Question for tech divers: thought experiment.
Would you theoretically use a set of MK2’s on your back mount doubles with confidence? ….with any 2nd stage of your choice, it doesn’t have to be a Scubapro.
Gas density at IP exiting the first stage is still a thing regards depth.. just saying.
Yes, if the second stage is really balanced...
Years ago, indeed, when most second stages were NOT balanced, and there was no SPG, it was considered a good safety measure that when the pressure in the tank was reducing, breathing was becoming progressively more difficult. So you had to pull your reserve rod way before being truly "out of air".
Using a balanced reg, instead, you switched suddenly between breathing normally to not breathing at all, and this can be a problem when diving with a reserve valve and no SPG.
scrane
Contributor
Yes, thanks.
It's been a while since I climbed back on the boat with less than 750 lbs.
What I'm wondering is if I can expect the same performance from my Scubapro d400 that I get with a balanced Conshelf first. I have no diving experience with an unbalanced first. If there's no appreciable difference I have a nice shiny Mk2 in the basement I'd like to take on my next trip. I know a lot of people don't like the straight through radial hose distribution, but it works for my setup.
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