Titanium or Not ??

[paulwlee]

Atomic M1: excellent piston performance characteristics but I don't like the swivel - there are better solutions for hose routing issues that don't sacrifice flow rates. Good service can be hard to find and I'm leery of them in cold water.

Disclosure: Although I've been diving with all of these regulators except the Atomic,

Correction: There is no second stage swivel on the M1. This comes on the B2 and T2, but you can get them without it if you want.

 

[paulwlee]

Ti first stage.
If you have lots of money, then why not?
The advantage I see for a Ti first stage is that you can be very careless with the regulator and it will still look new and perform like new (to an extent).
The brass first stage inevitably will have its chrome plating eaten away gradually, and depending on how well you treat it, brass will begin to show if used for a long time.
In terms of performance, with a brass model the internal surface that the o-ring moves against will accumulate a little bit of corrosion, increasing breathing resistance over time until it gets cleaned during service. This issue is minimal if you take decent care of your regulator and have it serviced at least once every 2~3 years, but still, a Ti first stage would be more immune to this kind of degradation.

Like most people here I wouldn't buy a Ti first stage myself since I can put that money to better use somewhere else, but if I were rich then I wouldn't think twice before getting one for my single-tank rig.

 

[Sadamune]

I agree with paulwlee, the only drawback (for recreational divers) of titanium regulators is their price. Of course, one needs to pay attention to the user manual, but as long as it is used responsibly, a titanium regulator will serve a diver very well.

Also, if one were willing to purchase used gear, a titanium regulator can often be purchased for around half of the retail price. Doing so ameliorates the only significant difficulty that most divers have acquiring such excellent equipment.

Sadamune

 

[UaVaj]

with a brass model the internal surface that the o-ring moves against will accumulate a little bit of corrosion, increasing breathing resistance over time until it gets cleaned during service. This issue is minimal if you take decent care of your regulator and have it serviced at least once every 2~3 years, but still, a Ti first stage would be more immune to this kind of degradation.

Like most people here I wouldn't buy a Ti first stage myself since I can put that money to better use somewhere else, but if I were rich then I wouldn't think twice before getting one for my single-tank rig.

Thanks for that informative information. At least now I see where that extra $$$ is going toward.

MK25/S600 is still the better buy.

The unusual design of the X650 second has some distinct performance advantages

What are the advantage of the X650. I could reallie care less about looks. Easy to breathe - having a regulator that like not having one on is my #1 priority.

I reallie like the diver adjustable Inhalation Effort and adjustable Venturi Initated Vacuum Assist features of the SP second stage. Looks like SP will get my business in term of regulator since all the other brand you listed didn't show any unique features that was above and beyond what SP offer.

 

[elmo6s]

I personally dive Apeks XTX50 / DST - used to have the SP MK25/S600 - I hear it is more reliable in cold water, and my LDS services it, so those are big plusses... I hear great things about the Apeks XTX200 (~$700) - it will be my next reg, and it is supposed to be fantastic. Just my $.02

 

[SDAnderson]

What are the advantage of the X650.

We're going to have to trust ScubaPro a little on this, but they maintain that this regulator breathes easier than any of their others primarily because the design of the case and the placement of the valve allows for a more laminar (smoother) air flow and because of the way the valve orifice is designed and placed inside the box. If you look at the regulator, you'll see that the valve enters the box at the top instead of in the middle (like most regulators) and that it directly targets the mouthpiece. The exhaust ports are also located at the bottom of the box, out of the way of that inhalation airflow.

I'm not an engineer and can't tell you if they're pulling our collective legs about the airflow characteristics but I've seen the Ansti WOB figures for many of the better second stages and the X650 is at least as easy to breathe as anything I am aware of. According to SP, it's as good as anything in the marketplace today. It's an expensive second stage and the law of diminishing returns seems to be in effect but if raw performance is your criteria, it looks like the best available.

 

[NYBoilermaker]

Two quick questions:

#1. Is it true that ScubaPro doesn't allow merchants to to sell other manufactures products along with ScubaPro's?

#2. I've heard that switching from air to EANx with a Ti regulator could cause problems with burning? Can someone explain how that happens?

Thank you,
NYB

 

[SDAnderson]

#1. Is it true that ScubaPro doesn't allow merchants to to sell other manufactures products along with ScubaPro's?

There is no truth to this statement, whatsoever.

#2. I've heard that switching from air to EANx with a Ti regulator could cause problems with burning? Can someone explain how that happens?

Titanium is flammable at relatively low temperatures and, combined with high oxygen mixes and adiabatic compression heat, there is a risk of spontaneous combustion. How much of a risk is the subject of debate but recreational users (no more than EAN40) are probably safe enough.

 

[Sadamune]

Titanium is flammable at relatively low temperatures and, combined with high oxygen mixes and adiabatic compression heat, there is a risk of spontaneous combustion.

I don't think spontaneous combustion of titanium is the issue here. However, spontaneous combustion of volatiles in a dirty regulator is an issue. I believe the reason a titanium first stage regulator must be O2 clean before using EANx is to prevent any combustible contamination from unclean air potentially creating an ignition source for the metal. Titanium won't necessarily burn in the presence of high partial pressure O2. However, if a fire starts in another combustible substance, such as microscopic droplets of oil from an air compressor, then that fire can potentially ignite the titanium and be difficult to extinguish. So, as long as a diver remembers to have a titanium regulator O2 cleaned before using EAN40 or less, everything will be fine.

A speculation regarding future uses of titanium in regulators and in high ppO2 environments in general ---> Special surface coatings on titanium alloys, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD) coatings, might eliminate the possibility of combustion by shielding the titanium with an extremely hard and inert layer. Also, if the titanium alloy used was specially formulated for use in high ppO2 environments then the likelihood of combustion would be decreased even more. In fact, I've read that there are some types of beta alloy titanium that can be used in O2 environments unsafe for conventional Ti alloys. The future looks quite promising for titanium in SCUBA.

Sadamune

 

[fisherdvm]

In 10 years, new technology will arrive. And your titanium reg, though shiny and new from lack of corrosion, is not worth the extra money you paid.