Regulator assembly tools?

[omcfadde]

Hi,

I've been reading this forum for some time now, and figured it's about time to make a post.

I'd like to get some information on the proper (high-end) tools for assembling a regulator (assembling, not servicing quite yet.) I have figured I will need at least the following:

• Set of hex keys for port plug removal/installation (5/32" open end wrench)
• Christo-Lube MCG111 lubricant (manufacture specified)
• Second stage hose and LP inflation - 9/16" open end wrench
• HP gauge or integrated computer - 5/8" open end wrench
• Torque wrench to ensure torque of 40 in-lbs on all hoses.

This is all covered by the manual (which is irritatingly in imperial measurements), however, what the manual does not specify is exactly what kind of wrenches are required in order to be compatible with a torque wrench, nor which torque wrench is best suited for this use.

Please before anyone says "Oh, just tighten them finger tight plus 1/2 or 1/4 or 1/8th of a turn." No. The regs I'm buying are expensive equipment and I want to learn the right way of doing things myself. I respect that finger tight + X may be fine for you, and maybe I'm just being a perfectionist following the manufactures manual to the letter... but please, can we keep that debate to another thread?

So, here are the questions (and yes, I searched, but I only found threads with answers of "finger tight plus X")

• Wrenches: would prefer to buy a full set, but individual is fine. I do not want adjustable. What type do I need to be compatible with a torque wrench?
• What is an ideal torque wrench for 40 in-lbs and compatible with the wrenches?
• Do you need special hex keys for compatibility with the torque wrench? (Re-installing the port plugs and torquing to 40 in-lbs)

I doubt the final question (re-installing port plugs) will be something I would do often, but when switching from a dry to wet suit.

Advice and places to shop online much appreciated.

Thanks!

 

[Jimmer]

You need crowsfoot wrenches to work with the torque wrench.
Any 3/8" drive torque wrench should be fine.
You will need 3/8" hex key sockets for the torque wrench.

Any of that stuff can be found a decent auto parts store and most hardware stores.

And yes I use the "snug" method

P.S. what regulator did you buy?

 

[knowone]

With the variation in size of part and chrome thickness, a (high- end)
adjustable wrench, and doing "shop" and a measurement converter.

 

[knotical]

The only things I'd add to what Jimmer said would be to go with a "click type" torque wrench rather than a beam type for greater accuracy; and to choose one in which your desired torques are near the middle of the range (again for accuracy). As you've noted, common torques for what you describe are around 40 inch-pounds / 4.5 newton meters. This could move you toward a 1/4" drive instead of 3/8". After using your torque wrench several times, you will probably get a "feel" for it and might convert to assembling without benefit of the torque wrench.

 

[Wookie]

I have a 3/8 drive 0-120 in lb torque wrench by Snap-On for compressor maintenance. They are high dollar, but it doesn't lose calibration and I've had it for 15 years, works fine. You'll need a crows foot, but you will need to lower the torque setting by about 5 in-lbs to account for the greater moment of the crows foot. A decent torque wrench will come with instructions for exactly how to calculate the change. Get a set of hex sockets for the port plugs. They are used just like a regular socket.

 

[HenrikBP]

If you put the crows foot wrench at 90° to the torque wrench you shouldn't need to compensate for change in torque value.

Keep in mind that it is not the torque of the hoses and port plugs that seals the connection - it's the o-ring. So while I can appreciate your desire to do a "perfect" job, unless you're willing to shell out $300 plus for a torque wrench and annual (at least) calibration of that wrench, you're still just wingin' it

Henrik

 

[Mr Carcharodon]

You can buy hex bits and wrenches to meet your needs.

Some of the torque values are more important than others. In practice not many people will use a torque wrench to put in a port plug. But the torque value gives you guidance on how hard you should be pushing the end of a hex key. So in this case for a typical hex key a 8 or 10 pound push at the end will give you the torque you are after. There are other places (e.g. swivel nuts) where you have a undercut nut where not over-torqueing really is important because those parts can fail if over tightened. Anyway there is certainly no harm in using a torque wrench for everything even if it is not necessary.

I do not understand your distinction between assembly and servicing. If you have taken your regulator apart you might as well clean and lube parts and replace the parts that need replacing. Most of the work has been done already. Good luck.

 

[redacted]

Before you go out and buy tools, you might want to study the mechanics of your regulator. Most connectors have a torque specification. It is just a normal part of designing such a device. Some torque specification are very important so things do not loosen in use and to avoid damage to threaded connections. With hoses and port plugs that employ a compressed o-ring seal, the reason for a torque spec like 40 in-lb is to make sure it does not loosen. The torque is working on compressing the sealing o-ring and there is little danger of doing any metal to metal damage without grossly exceeding the spec.

Someone with the best torque wrench money can buy who does not know (understand) what they are doing, can still screw things up. Tools do not correct for lack of knowledge.

Very few 3/8th inch drive torque wrenches will provide accurate results in the lower in-lb range. Most are graduated in ft-lb. For torque values in the 0 to 100 in-lb range, a 1/4th inch drive wrench will usually provide more accurate results at more reasonable prices.

 

[LeadTurn_SD]

Hi omcfadde,

Welcome to the "Dark Side".

Re-read awap's post carefully. Tons of gems and hard-earned wisdom summarized in just three paragraphs.

Don't take any wrench, torque or otherwise, to the soft marine brass until you understand which parts need to be accurately torque'd, and which parts really should just be "tight enough" so they don't come undone.

Scuba Tools Is a great source for specialty tools for various regulators, and a very good regulator text is on that site.

Have fun on your journey, learning to service your own regs is a VERY worthwhile endeavor.

Best wishes.

 

[Capt.Gene]

Most owners working on their gear over tighten everything, which can lead to tool marks when it eventually needs to come apart.
Good on you for getting the right tools.