Your wisdom

[Jess' Diving Adventures]

Hi,

Have been trawling through the posts and searching like mad but would like some help if at all possible (be kind this is my first post!) Am going to be investing in my first reg having always just used the diveshops ones in the past. I am getting little lost in all the info thats floating around.

Specifically i am looking at ScubaPro Regs. I am going to be diving mainly in warm water but want to make this purchase an investment (having said that there are not unlimited funds) and may want to try colder climes in the next couple of years.

So, to my questions: Should I plump for a Mk25 or is MK16/18 going to be OK and what is the difference between a G250 and a S600 besides looks?

I suffered from mild TMJ disorder (pain in the jaw around my ear brought on by 'biting on the mouthpiece) at the end of 2 1/2 months of diving daily this summer. Will this affect my choice of 2nd Stage?

Sorry if any of this has appeared elsewhere, appreciate your help or redirection to useful info.

Cheers, Jess

 

[Parrothead_Diver]

I don't know about the Scubapro regs because I dive with Zeagle.

As for the Sore Jaw, try a second stage with a swivel. This should relieve some of the pressure on our bite. I know alot of people do not like them (read DIR) for various reasons, but it might help you.

P.S. Welcome to Scubaboard....

 

[Jason B]

For the jaw fatigue, get a "comfo-bite". Wonderful mouthpiece! Come standard on Apeks (hint hint).

Jason

 

[Poseidon8118]

Scubapro is an excellent choice! Get what you can afford without killing your budget. Over the past 18 years I’ve acquired four different setups. My first setup was a Dacor Pacer/350 first stage, Totally Balanced Octo and Gauges (still in service). My second setup was a Scubapro G250/Mk20 combo (best breather). My third was a Sherwood Maximus, Apeks ATX 50 Octo (use this one the most) and my forth is a Parkway Atlas 2 I got for sixty bucks with a Nova2 Octo and Tusa SPG. Parkway is no longer in business but the setup is a good backup for my son when we go diving, and for $60.00 worth it. I also have a Sherwood Minimus which I used before the Apeks.

I listed all of this stuff to help you see that there is no right or wrong, better or worse answer out there. I would opt for an Aqua-Lung Comfo-Bite mouthpiece for the Scubapro. This may help your TMJ disorder. I have them on my Scubpro, and Sherwood/Apeks setups. You can buy them for around $15 USD.

Hope this helps!

 

[scubapro50]

Scubapro is a good choice ... I own 7 different regulators including a Voit singlehose and 5 Dacor (including an R4 doublehose) and by far the best one has been my MK10. Over the past 12 years it has never let me down. It breaths as good if not better than most of the new "high" price models and the 1st stage is one of the most copied in the industry. Get the MK16 with the 250 2nd stage. You won't be disappointed. If you get the chance read www.scubaboard.com/t70450-.html about how some of the other diving companies have not honored their warranty on products they have made.

 

[Chad Carney]

Welcome to the board Jess!

Scubapro makes some fine regulators; I started with them in the early 70s.

Now I have mostly all Zeagle gear. The Flathead XI is a bomb of a regulator! (Great for cold water too!) I don't keep my old gear.

The store where I taught scuba and managed, carried every line of gear made.

Now I rep for Zeagle.

Chad
cubera@ij.net

 

[Vie]

what is the difference between a G250 and a S600 besides looks?

Size. The S600 is smaller and there is another 2nd stage called the S600 Classic which contains more metal parts (cover and adjustment knob). If you don’t mind the size, the G250 is a perfectly good and reliable 2nd stage.

 

[DA Aquamaster]

The Mk 25 has a poor reputation in very cold water (less than about 45 degrees) for freezing up. This normally seems to occur when it is paired with the S600, which has a tendency to develop a very slight freeflow in very cold water that then increases the adibatic colling load on the first stage. High presure tanks also increase the cooling load so low pressure tanks (2250 to 2640 psi) area better choice with this reg.

That said I, put a few hundred dives on a Mk 25 D400 in water ranging from ice dives to bottom temps in the low to mid 40's and never had problem with a feeze up. So with good technique, a decent second stage and low pressure tanks, freeze ups are not a concern. I still dive a pair of Mk 20 D400's.

The Mk 16 is basically bullet proof in cold water. It is perhaps theoretically possibel to freeze one up, but I have never seen it happen. It is not sealed but the ambient chamber is very open with excellent water exchange and it is about as far away from the cold portion of the reg as it can get. It's a reliable reg for ice diving. Raw performance is a lot less than the Mk 25, but that is a relative thing. The Mk 25 has a flow rate of approximately 300 scfm, while the Mk 16 has aflow rate of approximately 170 scfm. It sounds like an important difference but it isn't as 170 scfm is more than enough for any diving situation.

The Mk 2 is also extremely reliable in cold water. It is a medium performance reg however and the flow rate of 92 scfm normally restricts it to recreational limits of 100-130 ft. It is also unbalanced and is usually paired with an unbalanced second stage so it tends to breathe a bit harder than a MK 16 or Mk 25 at low tank pressures.

The G250 and S600 share the same internal parts, the G250 is just in a larger case and uses a larger diaphragm which offers some significant advantages. The G250 has has a better reputation than the S600 in demanding conditions and offers the same to slightly better performance for about $40 less. I cold water, I'd choose the G250 long before I would choose an S600.

Jaw fatigue is much more a factor of mouthpiece design and hose lenght than it is second stage size or weigtht. Larger second stages are a bit heavier (although the difference with composite cases is very slight) but they also displace more water so the extra bouyancy offsets the additional weight and in most cases larger second stages are actually closer to neutral bouyancy in the water than smaller cased regs. So don't believe all the marketing hype about small being better - it isn't.

A good mouthpiece design is important. The stock SP mouthpiece is actually pretty good. I also like the comfo-bite mouthpiece as it transfers most of the load to the roof of the mouth and you can be slack jawed and still hold it in your mouth. The long bite tabbed custom mouthpieces also have a following, but they are problematic in an air sharing situation and in my opinion pose a potentially serious safety concern.

Reduced jaw fatigue depends most on having a low pressure hose of the proper lenght. A hose than is a couple inches too long will push the second stage to the left and one that is too short will pull the second stage to the right. Both conditions require a lot more force to hold the reg in place. This is probably the largest single factor in jaw fatigue when diving and it is ironically a factor that practically no one considers. You need to see if your hose s pushing your second stage one way or the other and then switch to a longer or shorter hose if needed.

In summary, a Mk 16 G250 with a comfo-bite mouthpiece and an LP hose of the proper lenght would be a good choice. Ideally, the Mk 18 would be even better if you can find one. It is a Mk 16 but with a swivel turret that improves hose routing and also makes the second stage LP hose lenght less critical. They are not marketed heavily in the US, I suspect because they would not fit with SP's marketing strategy and would steal sales from both the Mk 16 and Mk 25.

 

[Jess' Diving Adventures]

Thanks so much for the advice, I am now in possesion of some knowledge having visited the dive shop today and had a look at regs and a chat with a nice lad. My new question is...

Whats the difference between a S600 and an S550. From what i am told they perform the same just the S600 has a twizel thing to help fine-tune during the dive (is this really necessary?)

Also, as im UK based are internet sites such as Leisurepro.com reliable to make a purchase from once i have made my choice as I will save 50% by buying this way (I will live withthe guilt of not buying from the dive shop by spending the money diving with them!)

Again, many thanks,

Jess

 

[scubatoys]

Whats the difference between a S600 and an S550. From what i am told they perform the same just the S600 has a twizel thing to help fine-tune during the dive (is this really necessary?)

Yes, the only difference is the 550 is not adjustable, while the 600 is. Both are Pneumatically balanced (If you want to know about that, check out http://www.scubatoys.com/store/joelarry/jlpneumatically.asp) and great regs... just make the call on whether it's worth the extra money for an adjustment knob.