Which piston reg is the best to practice rebuilding on? Preferably an SP reg.

[elan]

Basically the subj.

In my possession I now have new MK25s which I plan to rebuild myself not sooner than in a couple of years from now. MK2 is in plans of purchasing for an O2 deco later this year.

So far I have been rebuilding diaphragm regs including Apeks, Zeagle and USD DH regs.

I have ordered some SP tools already, and Im planning to stay with SP for the pistons.
Thanks a lot in advance.

 

[NotSure]

I haven't rebuilt very many piston first stage regulators yet, just a few MK10's, an MK5 and a MK2, but I think I can safely say that it you would have a hard time finding a regulator easier to rebuild than the MK2. I've read here that some consider the Mk25/Mk20 easier to rebuild than the MK5 and Mk10. If that's the case I think you will find your MK25 while having a lot more O rings than the MK2 will still be a relatively simple rebuild. I bought a NOS MK20 recently and since it's been sitting around since 1998 I am definitely going rebuild it before I us it. I'll let you know from a beginners perspective what I think of the MK20/25 rebuild when I get around to it.

 

[smorneau]

I am doing my first mk10 as we speak, kits are easy to find on ebay or "Vintage Double Hose". So faw so good as long as you have the right tools. I though I read somewhere the other day here on SB DYI that the mk2 should not be used for o2, someone else should chime in on this because I am not sure.

 

[Fishpie]

I must admit to getting confused and frustrated with MK20's and 25......too many different coloured bits of plastic around the piston that kept changing from year to year.
I'm in the process of dumping them in favor of 5's and 10's.

You can pick up MK10's very very cheap that are far too good to be used just for practice.
Oceanic balanced piston is another good one (basically it's a MK5).

 

[elan]

I am doing my first mk10 as we speak, kits are easy to find on ebay or "Vintage Double Hose". So faw so good as long as you have the right tools. I though I read somewhere the other day here on SB DYI that the mk2 should not be used for o2, someone else should chime in on this because I am not sure.

I was thinking about MK2Plus , which, as per a conversation with an experienced tech, is the only SP reg supported officially by SP for O2

 

[redacted]

I suggest starting out with a good Mk5. Make sure it has 5 LP ports, 2 HP 7/16 ports, and a heavy yoke. When you have done both, you may just decide to stay with the Mk5. I did.

 

[elan]

I suggest starting out with a good Mk5. Make sure it has 5 LP ports, 2 HP 7/16 ports, and a heavy yoke. When you have done both, you may just decide to stay with the Mk5. I did.

Can they be converted to DIN by any chance ?

 

[Zung]

Since you have rebuilt Apeks, Zeagle and USD before, it means you already know how NOT to mess up a reg, so I see no good reason to start all over again just because it's piston vs diaphragm.

And since you mentioned MK25s (plural), I see no good reasons why you should buy other SP gears just to pratice on. Might as well start on the MK25 proper. Just pick the urgliest one first.

We have 6 MK20/25's for the 4 of us as our main rig, they breathe wonderful, servicing is very straightforward, less parts than the diaphragm regs, and no special trick or tools required.

I have about as many MK5/10's. They're good but I don't think they're better than the MK20/25's. Their main selling point, as far as I'm concerned, is they can be serviced for $5 in parts.

The MK10's use the standard DIN kit. The MK5's are special.

 

[elan]

Zung thanks a lot... I might just look at getting a used 25/20 to practice

 

[smorneau]

What is the difference between an mk5 and a mk10?