If I was, I'd have killed myself by now.....
You aren't funny?
Regulator Geeks: Scubapro Mk19EVO - teardown & discussion
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You aren't funny?
lactose intolerant...
Now, that's funny.
...get a room.
sorry, been drinking... been a rough week...
Andrew Dawson
Contributor
It was mentioned a few times...how grit, sand, silt will get into the ambient chamber of the MK25 and as the piston cycles from the diver breathing....that wears out the shiny chrome parts of the reg...the reg is wearing out. To fix this, you need to sand down and polish the ambient chamber walls.
The piston in the MK25, where the knife edge is at the top of it, that seals with the HP seat...that knife edge wears as high speed air from the [high] pressure tank has tiny bits going zipping by and around that edge, that edge gets worn or has a tiny groove from a high speed bit flying from the tank...and then you get a not so great seal between the piston and HP seat, leading to IP creep. To fix this, you need to sand down that knife edge to make it sharp and smooth again.
Sanding chrome plated brass can only be done for so long
So, using the MK25 provides mega performance...but...by design...it also wears itself out.
As far as I know, the diaphragm regs do not do this. So they can consistently provide [their] high performance over their lifespan without any sanding or wearing of internal parts. The service kit is all that is needed...no new parts over time. The MK25 will eventually need a new piston/ambient chamber. It is TBD how long their lives are...depending on how much and what type of grit is in there, how much the reg is used, how aggressive the service tech is at sanding [or never sanding], etc.
From this regard, the MK19 Evo [or environmentally sealed diaphragm] regs are superior to the MK25 [unsealed piston regs].
I do not claim to be an expert...am just sharing what I have heard that made sense to me...and I have seen with my own eyes when rebuilding my own MK25s. These used to be MK20s that were converted to MK25s, just FYI.
Have one for me...I have not had one in over 8yrs...but...I may have had some sort of edible candy that is legal in my state that makes you unwind as well
It was mentioned a few times...how grit, sand, silt will get into the ambient chamber of the MK25 and as the piston cycles from the diver breathing....that wears out the shiny chrome parts of the reg...the reg is wearing out. To fix this, you need to sand down and polish the ambient chamber walls.
The piston in the MK25, where the knife edge is at the top of it, that seals with the HP seat...that knife edge wears as high speed air from the [high] pressure tank has tiny bits going zipping by and around that edge, that edge gets worn or has a tiny groove from a high speed bit flying from the tank...and then you get a not so great seal between the piston and HP seat, leading to IP creep. To fix this, you need to sand down that knife edge to make it sharp and smooth again.
Sanding chrome plated brass can only be done for so long
So, using the MK25 provides mega performance...but...by design...it also wears itself out.
I know about this VERY infrequent issue that isn't anywhere near a real thing. You can't make such a sweeping statement based on a very infrequent exception.
This isn't accurate as you are presenting. You will replace more internal parts in the diaphragm first stage over the life span of its life than the piston regulator. You are grossly exaggerating the matter.
The MK 25 will suffer from shore diving, it takes a lot of dives but it does happen, denial is pointless.
there is a sealed MK 25 experiment going on at the moment and the MK 20 boot is a good one though very rare, both of my 20’s have them.
there is a sealed MK 25 experiment going on at the moment and the MK 20 boot is a good one though very rare, both of my 20’s have them.
My students, friends and I use MK25 diving from SANDY Libyan shores, very fine desert sand, without any issues at all. There are days in the summer, a very long summer here, where the sand storms blow and it feels like sand paper on your face.
Been doing this for years and years. It doesn't stop there, our water that we use to rinse our regulators has high mineral content but no issues inside the first stage. My friends who use the MK25 never service their regulators, there are no service centers in Libya (I do service my own and my dive center's equipment every a couple of years however).
I am not denying it that it happens but it is so insignificant that it isn't an issue to be taken into consideration comparing the worthiness of the MK25 vs. others.
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