Questions on Regulator Maintenance

[Couv]

Are there any other more costly tools that are a must more reg maintenance?

Refresh my memory. What first and second stages are you servicing?

... are ultrasonic cleaners a must when maintaining regs?

No, if you're only going to maintain your own regs. A set of brass and/or nylon brushes should do the job with the help of elbow grease. I bought a cheap gun cleaning kit and it is very useful for getting into tight spots. An ultrasonic cleaner is a "nice to have" item that can speed things along if you're servicing several regulators. Specialized tools take priority in the regulator maintenance budget. Contact @herman and let him know what regs you're working on. He makes custom tools and won't sell you anything you won't find useful.

...
are there so called beginner regs that would be easier to learn maintenance from?

SP MK2/MK200/MK3 first stage
SP 109 second stage

 

[TheWarmerTheBetter]

The accuracy of the IP gauge is not really important- within reason- since all manuf give a range of acceptable IPs, usually in the 130-145 psi range, it is not critical to have the exact value. What you are really looking for is a constant return to a value within the range - the reg returns to xxx psi every time you cycle it and that the pressure does not change- the IP does not creep. Any gauge, even one way off calibration, can show you that information.

Another nice to have tool is one to measure cracking and exhaust pressure of the reg. While Magnehelic gauges are cool, you can easily build a U-tube manometer for very little money that will work quite well. It's accurate and fun to make. Here is a discussion we had a few years back you might find helpful. DIY regulator test/flow panel

A general comment on regs servicing is don't over tighten parts. Most everything in a reg that is sealed uses an oring. Orings, unlike gaskets, do not require a tight torque to function, tightening them more only makes things worse. Obviously, you don't want things coming apart by themselves but there is never a reason to crank down on regulator.

You can't really hurt yourself doing regulator maintenance, so long as (as someone else mentioned) you don't pressurize your first stage without a second stage or pressure relief valve attached.

herman makes three very good points.

All the regulator manufacturers give a range for the IP and so long as your first stage consistently locks at a pressure it's not a big deal if it's a few PSI one way or the other.

Manufacturers also give a "cracking effort" which is measured using a Magnehelic gauge (if you want to be official about it), or a U shaped tube with some water in it. You can buy Magnehelics for pretty cheap on ebay. You want one that goes up to about 2" water. The "cracking effort" is a less essential setting than the IP, and you could totally get away with doing it by feel (how the reg breaths). If you service your reg and you have to really inhale to get air to start then make an adjustment, if you start a dive and the second you move your head your reg starts flowing, then make an adjustment in the other direction. As a side note, most octo regs are set with the maximum pre-load on the spring that controls the cracking effort (the maximum cracking effort the regulator can be set to).

I think herman's most important point is not to over tighten things. I know when I started working on regulators I wanted to crank things down. Pretty much everything needs to be just tight enough that you can't loosen it by hand, but no tighter. The tighter you make it beyond that the more likely you are to cause an issue (especially when you're tightening the cap that holds the diaphragm in place).

The only other point I would add is one that I think someone else mentioned: Make sure you don't scratch anything. If you use brass or plastic o-ring picks you should be perfectly safe. That being said, steel o-ring picks are much stiffer and more durable than the brass and plastic ones, and I much prefer them. If you're using them just be gentle.

 

[NotSure]

Use Cristolube but use it sparingly. It is a far superior product to silicone and a must if you're doing enriched gas. Static o-rings only need a thin film - sealing is accomplished through compression of the o-ring, not by the lube.

I would generally agree but when buying a used regulator would prefer a 40 year old regulator with silicone over a 20 year old one with Cristolube. Silicone lube is just fine for most divers.

 

[buddhasummer]

I only ever use silicone, no enriched diving for me. The only time I used christo was when I had ip problems on a MK10+.

 

[herman]

I agree, all I use is DOW 111. It will not separated like some of the other lubes, is stable and unless you are using high O2 (over 40%) mixes there is no need for expensive lubes like Cristolube. I have seen regs that have not been serviced in many many years with the lube still in prefect condition.