ScubaPro MK25/S600 - Why SHOULDN'T I?

[gijo1977]

So, I have just bought a couple of MK25/S600 regs from a guy getting out of Diving. I am happy with the performance weighting etc... But I am also wondering if SP have a kit to replace the existing plastic air barrel with a metal one similar to their G250V ?? Considering that the s600 is the top of their lineup, I would expect that they would offer it? Can you use the G250V part to upgrade it?

 

[DA Aquamaster]

In a word - No.

The air barrels are distinctly different as are the adjustment knobs and cases.

The G250V is designed on a full size case with a full size diaphragm while the S600 is basd on a smaller case and smaller diaphragm so there is no way you can shoehorn a G250V air barrel into one.

In the good old days it was possible to upgrade, for example, an unbalanced R190 "Adjustable" to an R156 "Balnced Adjustable" or an unbalanced G200 to a Balanced G200B or even a G250 as parts commonality was higher with a single case size. At present you could probably upgrade a G500 to an S600 (but if it is the older US made G500 with the black purge cover, its already better than an S600) but that is about it.

 

[halocline]

I'm sure you can't, it's a different size case. I don't know a great deal about the S600, but I think the G500 was it's predecessor and it might have a metal air barrel. Awap would certainly know, he has both. The S600 has kind of a 2nd balance chamber in the air barrel near the adjustment side that might act as a seat saver of sorts, I'm pretty sure the G500 has the same sort of arrangement.

In SP's infinite wisdom, the plastic air barrel is the upgrade. See why there's a little cult that likes the old stuff better?

Edit: DA already answered your question!

 

[vixtor]

I would also vote for MK17/G250V. It will give you more air than you will ever need (so the extra of MK25 is not really needed), and will not freeze as the MK25.

A friend said about my MK17/G250V, that it was like it was pushing air into my mouth.

 

[runway1]

How do we dive you ask? Well, we're strictly warm water divers these days, rarely anything colder 75-80 F....

DAZ,
Where in socal do you dive 75°-80°? I dive socal shores and Channel islands regularly.

Anyhow, Atomic regs are also about the best in the industry and are located in Huntington Beach, CA. Scubapro is in El Cajon (near San Diego). Each are, without question, top of the line. So is Apex but they're furr-eigners (so am I so I can say that and still be PC:14. I think it's comforting knowing that your factory is near with parts and face-to-face service, when necessary.

Also, Atomic has nice swivels on the primary and secondary which offer very comfortable operation. This may be a factor - or not. They're smaller and lighter than the SP as well, which may also be a factor - or not.

I've been diving my env. sealed Atomic first stage with swivel on a Z2 seconday; love the thing. I don't think you'll go wrong with either, just my 2 cents.

 

[gijo1977]

So the short answer is NO to the Metal air barrel upgrade from a G250V. OK

But another question: If my Fitter/Machinist friend was motivated (He is an armourer) could he produce a metal version of the air barrel to replace the plastic one? and If such a mission was to take place what kind of stainless steel or alloy should be used? I would ensure it was turned and milled from a single piece if possible.

Is there any reason it wouldn’t work, or possibly damage the reg?

And yes I know I should have got the right kit first up etc... but that is the trick when purchasing gear at a really good price, sometimes the other option is just not competitive. Also it kind of interests me to produce this kind of DIY part? If it woked would it infringe copyright to sell the parts? or is it like a car modification??? just interested.

Sorry if this is a hijack

 

[halocline]

But another question: If my Fitter/Machinist friend was motivated (He is an armourer) could he produce a metal version of the air barrel to replace the plastic one? and If such a mission was to take place what kind of stainless steel or alloy should be used? I would ensure it was turned and milled from a single piece if possible.

Is there any reason it wouldn’t work, or possibly damage the reg?

Well, there's DIY, and then there's extra DIY, which I suppose this falls into. While I admire your can-do attitude, it would be much easier to buy a G500 on ebay or from another diver. You'll get the metal barrel, (I think) you'll probably like the reg better than the S600, at which point you can sell the S600 and be done with it. And, it will cost WAY less than having a machinist fabricate it. If you insist, chrome plated brass is what you would want to use. So you'll have to get your other friend the chrome plating guy involved too.

Besides, you're doing this to get rid of drymouth, right? Well, the metal air barrel will help some, but an old metal case balanced adjustable would help way more. Not only is the entire interior surface metal, but there is less noticable venturi assist, which I believe does a lot to reduce drymouth.

Sorry Daniel, eventually I'll convince you to get older gear!

 

[Daz]

DAZ,
Where in socal do you dive 75°-80°? I dive socal shores and Channel islands regularly.

Short answer - we don't. I used to do quite a bit of cold water stuff when I was actively teaching, but nowadays almost all of our dives begin with a plane ride...

 

[Packhorse]

Im with Mattboy.
Infact I have sold 2 S600s (in good condition) and upgradded to 109's then serviced them with G250 kits and springs.
I much preffer them to the s600's not to mention they are cheaper. I managed to buy 3 109's service them, a MK2 and MK5, hoses and SPG and still have change from selling my S600's

 

[gijo1977]

Nice one Matt,

I dont really have any issues with older gear, other than the problem of service and support in Australia. The market for these regs is much much greater in the US and so mostly there are no real issues with diving more vintage gear over there.

Regs like the D300/350 are next to impossible to get service kits for in Aus because the marketplace is so small, so other vintage regs are now suffering the same fate. Australians have a great habit of upgrading to the latest gear pretty quickly, which plays right into retailers hands....... and out of my pockets I am not too concerned with the Dry mouth problem, i am sure I will get used to the situation, but it was just a thought...... So stainless is less reliable than chromed brass? (No I dont have mates who do chroming)

I got the S600's and Mk25's for a very good price, so I wasnt/am not too concerned.

*Edit* Is it the "Housing" that is known as the air barrel? PN 11600022? This part is the same across the G500 and S600 (I assume it was plastic in the G500 as well. Or I might be misunderstanding which PN is the Airbarrel.......