Reg services

[BlueWaterDiving]

I'm so glald that I'm able to do my own regs. I worked on a Mares the other day for one of the shop that I do regs for and there was Us diver parts in there. They may work. But I glad I can do my own so I know that I'm getting the right stuff. Why would somebody do this??? The parts are all most the same price. That like taking your Ford in and getting Dodge parts.

 

[do it easy]

Oddly enough, I feel funny about buying o-rings from the toilet section of the hardware store (AKA the cave diving aisle) and putting them in scuba gear.

I know that they will work fine if the specs match, but it just gives me more peace of mind to get them elsewehere. I think part of the reason is that my LDS has a much wider selection and they usually don't charge me for them.

Edit: Ironically, the demand valve in a second stage is very similar to the valve that adds water to the toilet tank after you flush :11:

 

[300bar]

I'm so glald that I'm able to do my own regs. I worked on a Mares the other day for one of the shop that I do regs for and there was Us diver parts in there. They may work. But I glad I can do my own so I know that I'm getting the right stuff. Why would somebody do this??? The parts are all most the same price. That like taking your Ford in and getting Dodge parts.

Don't know witch parts you found, but I guess it was a HP valve.
And that is/was not uncommon,since the older Mares valves sucked.
The new Trimat.valve seems to be a lot better.

 

[PhilEllis]

This is too funny. Last week, we rebuilt an Aqua Lung Titan LX that had a MARES HP Seat. Guess some people freely exchange parts. Oh well.

Phil Ellis

 

[superstar]

Oddly enough, I feel funny about buying o-rings from the toilet section of the hardware store (AKA the cave diving aisle) and putting them in scuba gear.

I know that they will work fine if the specs match, but it just gives me more piece of mind to get them elsewehere. I think part of the reason is that my LDS has a much wider selection and they usually don't charge me for them.

Edit: Ironically, the demand valve in a second stage is very similar to the valve that adds water to the toilet tank after you flush :11:

Do I get free parts for life if I pay a toilet tech to service my toilet valve every year?

 

[deepblueme]

Some of the shop out there don't have the parts to service all the reg's they take in for service so they use the parts that they have.

A little thing about an o-ring is most of them are the same, the difference is what they are made of. A #10 is a #10 or a 010 depending on what catalog you get it from a viton o-ring from Scubapro is the same viton o-ring from Apache hose and rubber company or Trident.

Reg designers build the system around o-rings that are on the market already noone want to pay to make a special mold for an off size o-ring.
In other words the o in your car, toliet, reg or space shuttle are the same if it is n-buyntl or if it is called for viton. For a given size and hardness.

 

[Luis H]

This is interesting, but not surprising. US Divers used to make many of the parts for Voit and since Mares and Voit merged and many of their designs are based on the old Voit designs, it kind of makes sense.

It is good to know that there is some commonality of parts. It gives DIY like I more options. I have no problem picking the best parts from different manufacturers if they meet the same fit and function.


Oh, about O-rings, I would not normally use O-rings out of a hardware store. Hardware store O-rings are normally 70 Durometer, Buna-N. For most regulators it is normally recommended to use 90 durometer O-rings. The 70 durometer will work normally work on pinch, but I prefer to use the 90 durometer (one exception is the little O-ring on the HP pressure gauge spool).

 

[redacted]

I generally prefer the duro 70 (75 in viton) for all applications except the HP piston o-ring. The softer o-rings give you a little more sealing surface and will conform a little better to any imperfections. I always thought the higher duro o-ring was used where extrusion of a softer o-ring was a problem.

 

[Luis H]

In a gland seal (mostly seen in dynamic seals like piston O-rings and hose to second stage connection) the O-ring extrusion can be an issue (more in HP situation than LP) and therefore 90 durometer would always be my recommendation. IIRC, I have read that the higher durometer will also reduce wear on dynamic O-rings even if the pressure is low enough that O-ring extrusion is not much of a concern.

On static face seals and crush seals pipe fitting (like the hose to first stage connection, etc.) the durometer is not as important, but my observation is that 90 durometer tends to get pinched less during assembly. The 70 durometer may conform a bit better to small scratches. In this kind of joint I am not sure how significant is the difference between either durometer.


Here are different opinions in the subject, look under hardness:
How to Buy O-Rings For Scuba
Oxygen-Compatible O-Rings and Lubricant for SCUBA Applications

And they don’t actually totally agree with what I said or with each other.

Here you can download a copy of the Parker O-ring Manual:
http://www.optics.arizona.edu/optomech/references/423 references/Parker O-ring handbook.pdf


And here is a good source for O-rings:
O-rings Online Frameset

 

[Couv]

In an effort to keep things simple, I have gone to all FKM (Viton is a trade mark name used by Dupont) Shore A duro 90 o-rings and have yet to have a problem.

Why FKM? According to What are Rubber Materials? FKM is an appropriate material for static or dynamic applications with a temperatures range from -20 to +400 deg F, has an unlimited shelf life and it is also resistant to loads of different solvents and fluids. Why duro 90? Because duro 90 is suggested for all of my first stage piston stem o-rings. This way, I will never put the wrong duro o-ring in the body. Besides, if a plug or hose o-ring leaks, it will be a tiny leak.

You can buy o-rings in bulk MUCH cheaper than just a few at a time.

FKM is also O2 compatible provided one uses an O2 compatible lubricant like Christo-lube, Krytox, Fomblin and I think Bradycot (Sp?) makes one too.

I like the price and service at ORings, Inc. O-Rings, Inc. Since 1958 - Buy Online and they have more information about o-rings than you really care to know unless you are a geek like me.

c