Question about Scubapro MK 16

[scubatoys]

Larry @ scubatoys,

Why are you using MK 16 in rental?

By the way I came by for the scuba in ten city. Your store rocks!

Thanks! Glad you could stop by. That was a hectic day!

As far as the regs, we use them because when we picked up the line, the scubapro rep really wanted to get scubapro gear into our training and pool area. The idea being if students see it there, that is what they will want to buy... so they offer special incentives for training gear. I was not extremely familiar with their different regs at the time, and the rep suggested the MK16 R380 as a great rental reg. So we got a bunch.

When they came in, I could not believe how bad they were. And when I complained, they swapped out the 380 with 550 second stages for me at no cost. That helped some, but over all, I have not been impressed with the breathing or the dependability of the 1st stages.

So now we'll sell them off before next season and come up with a new reg to put in our rental fleet for next year.

 

[DA Aquamaster]

but over all, I have not been impressed with the breathing or the dependability of the 1st stages.

I am very surpised at this statement. I stopped using my Mk 20's in favor of Mk 17's and can tell zero difference in breathing performance even at depth in very cold water. And no one has ever complained about the breathing performance of a Mk 20 or 25. This comparision was also done with very nicely tuned D400 second stages (.7" inhalation effort) that would have illuminated any deficiency that existed in first stage performance. In fact, I have put a Mk 20 on one post and a Mk 17 on the other post and could tell the difference in breathing effort at the second stage.

I should add I got the same level of performance from the Mk 16, and would have purchased Mk 16's, if the Mk 17 had not been introduced at that time.

If you are feeling that performance is bad with the Mk 16 / S550 I'd supsect some unintentional and subjective bias on your part. From a performance and engineering standpoint, I suspect it is a second stage performance or adjustment issue, not a first stage issue. And with the S550 second stage, I'd lean heavily toward the second stage being adjusted to have an unneccesarily high inhalation effort. Locally, the LDS flow tests and adjusts all new regs before they leave the shop or go into rental service to ensure peak performance.

With regard to the Mk 17, we did a fairly long deco dive yesterday on a long exploratory swim at depths of 110-130 ft. with water temps in the low 40's and all of the Mk 17's on the dive performed flawlessly.

 

[scubatoys]

I am very surpised at this statement.

As I was very surprised to get bad performance of such an highly touted reg.

If you are feeling that performance is bad with the Mk 16 / S550 I'd supsect some unintentional and subjective bias on your part.

I would not call it subjective when I can take the units diving and see that I have regs that cost 1/2 the price that perform better.

From a performance and engineering standpoint, I suspect it is a second stage performance or adjustment issue, not a first stage issue. And with the S550 second stage, I'd lean heavily toward the second stage being adjusted to have an unneccesarily high inhalation effort. Locally, the LDS flow tests and adjusts all new regs before they leave the shop or go into rental service to ensure peak performance.

I know it's the second stage that is affecting the performance. The 1st stage issue is they have many more failures than other regs we deal with.

I know we can tweak and adjust them... I just don't think that new units out of the box should require a lot of tweaking.

Larry is mistaken in his assertion that SP is "selling" the Mk 16 to TUSA or that TUSA is marketing the Mk 16 as one of their low end regulators.

Scubapro designs regulators but does not waste money on production facilites for what would be relatively low volume production runs. Tabata has manufactured Scubapro's designs under contract to SP's design and quality specifications for decades.

Uh... no. The MK16, and now the same reg sold by Tusa is purchased by Tusa from Scubapro, and made in Scubapro's Italian facility... Not in Tusa's Japanese facility.


I have no problem with anyone buying a ScubaPro reg... We sell a lot of them. Just for the small difference in price, I'd tell them - just based on my experience with them, I'd spend the extra money and go with the MK25 reg, or go with a different reg all together.

And again... Just my opinion based on my experience with a lot of those regs.

 

[shooter226]

Thanks! Glad you could stop by. That was a hectic day!
As far as the regs, we use them because when we picked up the line, the scubapro rep really wanted to get scubapro gear into our training and pool area. The idea being if students see it there, that is what they will want to buy... so they offer special incentives for training gear. I was not extremely familiar with their different regs at the time, and the rep suggested the MK16 R380 as a great rental reg. So we got a bunch.
As I was very surprised to get bad performance of such an highly touted reg.
I would not call it subjective when I can take the units diving and see that I have regs that cost 1/2 the price that perform better.
I know it's the second stage that is affecting the performance. The 1st stage issue is they have many more failures than other regs we deal with.
I know we can tweak and adjust them... I just don't think that new units out of the box should require a lot of tweaking.
Uh... no. The MK16, and now the same reg sold by Tusa is purchased by Tusa from Scubapro, and made in Scubapro's Italian facility... Not in Tusa's Japanese facility.
I have no problem with anyone buying a ScubaPro reg... We sell a lot of them. Just for the small difference in price, I'd tell them - just based on my experience with them, I'd spend the extra money and go with the MK25 reg, or go with a different reg all together.
And again... Just my opinion based on my experience with a lot of those regs.

You should have left at noon with us to hit the Dallas titty bar circuit.

I was at a seminar of SP's and was told the Mk/25 has much higher flow rate than the 16, 17 or 18.

In our rental we use the Mk/2+. It just keeps on working. And you save a few bucks too.

Unless you are worried about freezing I think the SP piston regs are the best.

 

[scubatoys]

You should have left at noon with us to hit the Dallas titty bar circuit.

I was at a seminar of SP's and was told the Mk/25 has much higher flow rate than the 16, 17 or 18.

In our rental we use the Mk/2+. It just keeps on working. And you save a few bucks too.

Unless you are worried about freezing I think the SP piston regs are the best.

You are right... about most the stuff in your post.

And yes on the flow rate... but let's be honest. The MK25 has a 300 cubic ft per minute flow rate. And how big is your tank?? And you need that why? The limiting factor is how big the opening is on the valve. If you crack a tank wide open with no reg you can't drain an 80 in 20 seconds anyway. And yes, to do it over again, I probably would have the MK2 in rentals. Bullet proof, breath great, etc.

So many people avoid them since they are not balanced 1st stages... all that means is if you are at 100 feet with 300 psi in the tank - it will breathe hard. And if that is your profile, someone should be warning you to get your butt up!

 

[Greg Barlow]

And yes on the flow rate... but let's be honest. The MK25 has a 300 cubic ft per minute flow rate. And how big is your tank?? And you need that why? The limiting factor is how big the opening is on the valve. If you crack a tank wide open with no reg you can't drain an 80 in 20 seconds anyway. And yes, to do it over again, I probably would have the MK2 in rentals. Bullet proof, breath great, etc.

Perhaps just as important....What is the maximum flow rate of the attached second stage? Or, how about two second stages flowing at maximum...

I'll just keep using my 15+ diaphragm first stages with their "lowly" flow rate of around 170cfm. When you throw proper gas mixes into the equation, high flow rates become even less of an issue.

Greg Barlow
Former Science Editor for Rodale's Scuba Diving Magazine

 

[DA Aquamaster]

I agree with Greg that too much flow rate can be overkill.

A Mk 2 has a flow rate around 90-95 SCFM at a 3000 psi supply pressure and a 145 psi IP. The flow rate also tends to fall more or less proportianately with the IP but the Mk 2 on a near empty tank and an IP of 120 still provides adequate air at recreational depths to 130 ft. And I have spoken with cave divers who have used them on stage bottle with trimix at 250-300 ft and had more than adequate gas delivery.

The 177 SCFM flow rate of the MK 16 or Mk 17 is nearly twice as much and does not suffer the same hit as the Mk 2 does at low tank pressures, so if the Mk 2 is enough for all but the most demanding divngn situations, a reg like the Mk 16 or Mk 17 (or the older Mk 10 and Mk 10 Plus) will have it more than covered.

This is particularly true when you consider that the flow rate on even a high performace second stage is in the 65-70 SCFM range with an average unbalanced downstream poppet design second stage having a flow rate of only around 30-40 SCFM.

There just is not a need to nearly double the flow rate again, as is the case with the Mk 25 and it's 300 SCFM flow rate. In fact, I have spoken several techs, shop owners and cold water divers who feel the extremely high flow rate of the Mk 25 is it's achilles heel as it exceeds the heat transfer abilities of the reg and contributes to the cold water freeze up problems experienced by many Mk 25 owners in water colder than about 45-50 degrees.

----

And not to disagree with Larry too much more, but he is the only person I have heard about having Mk 16 reliability issues. I have not met anyone in person or corresponded with any other SB members who have had Mk 16 issues.

I cannot say the same thing about the Mk 25.

In any event, I would not suggest that a diver upgrade to a Mk 25 from a Mk 16 or 17, especially if they planned to do any cold water diving.

 

[rypark1999]

WOW!!! This sure did get a lot of debate going. It was very helpful to read the different opinions (although I gotta admit - some of the technical aspects I didn't understand and probably won't be able to tell the difference anyway). But it was all new stuff that I didn't know about which is great. Thanks everyone.

I did glean some important criteria I should have considered but didn't really think of (ie: 1) try/breathe the reg before buying and 2) I only plan on diving here in SoCal and warm water areas when I go on vacation - so definitely no issues about freezing a first stage). so two questions...

1) Would there be a difference in breathability if I tried breathing a balanced reg at the store (ie: on land)/pool (ie: 8 feet deep) as opposed to at deeper depths (ie: open water)?

2) What oceanic, zeagle and tusa models compete/are comparable with the SP MK17/S550? (considering I need two HP ports for a computer's AI transmitter and analogue SPG/DG)

 

[Jarrett]

My Oceanic has enough HP ports for my Atmos AI and Atmos 2/SPG setup. It's the Titanium one, but I think its the same as the Delta3/CDX5 reg. Larry would know for sure.

 

[Ben777]

Can anybody please comment, advise. Which is better, the Scubapro mk 16 and r38 . Vs TUSA R100