| It's really easy to pick up a low cost air | | | | size is measure on the I.D. A 1/2" air hose will |
| compressor at the local store anymore. But, how | | | | have a 1/2" I.D., regardless of the O.D. of the line. |
| do you get the air from the compressor to your | | | | Different air line manufacturers will have hose with |
| application? Folks that are plumbing up | | | | different wall thickness, so the outer diameters |
| compressed air lines for their garages or | | | | will vary.To connect PVC or RVC air hose |
| workshops at home, as well as the professional | | | | together, you can use the aforementioned |
| plant person, have a variety of options with which | | | | couplers and connectors. Usually the coupler and |
| to do connect the various air-lines available to | | | | connector has a "barbed" male protrusion, though |
| them.Usually the air compressor will come with a | | | | other styles are certainly available. Make sure the |
| rudimentary kit which will include a PVC (Polyvinyl | | | | "barb" size of the coupler / connector |
| Chloride) or RVC (Rubber Vinyl Chloride) air hose. | | | | corresponds with the internal diameter of your air |
| If not, these kits are available as | | | | hose. A gear clamp (do yourself a favour and |
| accessories.Rather than having a clutter of air | | | | purchase stainless steel clamps over carbon steel. |
| hose running across the floor (a trip hazard) | | | | A few pennies more, but much longer life) is |
| consider emulating the factory installation. Have | | | | installed on the hose first, and then the barb is |
| the discharge air line from the compressor run up | | | | inserted into the I.D. of the hose. After insertion |
| to the ceiling in the garage or workshop, and then | | | | of the "barb" the gear clamp is brought up the air |
| install "drop lines" down to the various locations on | | | | hose, over the area where the "barb" is inserted, |
| the bench where compressed air might be | | | | and tightened firmly. Using a small wrench to |
| used.The discharge from the compressor should | | | | tighten the clamp is preferable over a slotted |
| have, at the very least, a compressed air filter | | | | screw-driver which have a tendency to distort |
| where the air exits the receiver / tank, and the | | | | the nut.There are a variety of other fittings |
| smaller home-compressors will often have a | | | | available to join air hose. "Barb" to "barb" |
| regulator there as well. Compressing air causes | | | | connectors, "barbed" elbows, "barbed" T's, and so |
| water problems, and you can read more about | | | | on.If you are planning on using a lot of |
| this in my article in this E-zine entitled "Why does | | | | compressed air, hours worth of tool use at time |
| water run out my compressed air lines...". The | | | | for example, your drop legs should have a manual |
| regulator is necessary too, and you can read | | | | valve at the bottom of them and the supply to |
| about this in an article titled "Why use a | | | | your tool should be taken about six inches from |
| compressed air regulator" also on this | | | | the bottom. The manual valve will allow you to |
| site.Commercial installations of compressed air will | | | | drain the water that will accumulate there. See for |
| have a large general purpose compressed air filter | | | | more extensive information on plumbing for |
| at the compressor discharge, and then a filter, | | | | compressed air.As to the smaller air lines |
| regulator and sometimes an in-line lubricator (oiler) | | | | themselves, perhaps running to an air valve, |
| at each of the points where the compressed air | | | | joining an air valve to a cylinder, or even a small |
| is to be used, to help deal with compressor | | | | air brush or air tool, P.E. (polyethylene) is the air |
| generated water.The regulator will provide the | | | | tube of choice. It is chemically inert, won't rust |
| ability to control the pressure of the air to that | | | | with air-borne water, has a variety of fittings |
| particular application. You might want 90 PSI of air | | | | available, and is inexpensive.P.E. tube has a variety |
| to run a grinder at one drop line, but farther along | | | | of fitting styles available.It can be connected with |
| the bench you might only want 12 PSI for an air | | | | compression-ring (ferrule) type fittings. A nut, and |
| brush paint set up. Individual regulators give you | | | | then the ring fits over the tube, and once the |
| this capability. If you are installing a regulator at | | | | tube is inserted into the fitting, the |
| each drop location, remove the regulator at the | | | | compression-ring is brought down over the tube |
| compressor to ensure you have full pressure and | | | | and then the nut is tightened onto the thread, |
| flow to the air main overhead and the drop | | | | compressing the ferrule and created a seal. This |
| lines.The oiler use is dependant on what it is that | | | | type of fitting is available in many configurations |
| the compressed air is running.On your work | | | | including straight fitting, elbow, 'T' and so on.The |
| bench, at the bottom of each drop line, you can | | | | easiest fitting for plumbing P.E. tube is the "instant" |
| install a coupler. A coupler is a device into which | | | | variety. There will be a hole, correctly sized for |
| you can insert a connector. The coupler will be | | | | the O.D. of the tube, into which the tube, after it |
| "checked", meaning that compressed air is | | | | is cut squarely, can be inserted into the fitting. |
| trapped at that point until a connector is inserted | | | | Inside the hole will be an "O" ring type seal, and |
| into the coupler which opens the "check" and | | | | then a collar of small metal fingers through which |
| allows air to flow.Compressed air can then be | | | | the tube passes. When the air is turned on, the |
| supplied to the air tool or whatever you wish to | | | | P.E. tube swells a bit, and these "fingers" dig into |
| drive with compressed air via an air-line extension | | | | the surface of the tube, holding it in. The "O" ring |
| cord. You can purchase ready made or you can | | | | prevents escape of the compressed air. There will |
| make your own. They are lengths of air hose or | | | | be a small ring on the exterior of the fitting which, |
| tube with a connector at one end and a coupler | | | | when depressed, will "bend" the fingers out of the |
| at the other. The air tool will have a connector in | | | | way, allowing the tube to be removed from the |
| it's air port. When ready to supply compressed air | | | | fitting when necessary. This should only take place |
| to your tool, you simply insert your air-line | | | | if the air is off."Instant" type fittings may not |
| extension cord connector into the drop line | | | | work on soft air-line tube, such as polyurethane. |
| coupler, and the other end, which will be a coupler, | | | | Copper tube may present a problem too, as the |
| has the air tool connector inserted into | | | | "fingers" cannot easily grab the smooth surface of |
| it.Connectors and couplers are not all the same. | | | | the tube.There are some manufacturers that |
| Different manufacturers have differing styles and | | | | offer a line of miniature barbed fittings for tube. If |
| they are not usually interchangeable. When you | | | | you are installing many fittings in your application, |
| first start purchasing couplers and connectors for | | | | they may offer a lower cost solution. The |
| your air line, make a note of the brand first | | | | downside is that they significantly reduce the air |
| purchased, and purchase the same brand as your | | | | flow through the smaller I.D. plastic tube.For a |
| needs continue.I remember the difference | | | | good selection of air line couplers, connectors, |
| between a coupler and a connector by making a | | | | hose, tube and fittings, consider locating and |
| mental image of a "cup" into which I insert the | | | | visiting your local industrial supplier of fluid power |
| connector. The "cup" is the coupler.If it were me | | | | or compressed air components, rather than your |
| installing an "air main" and drop legs down to my | | | | local hardware or department store. Not only will |
| workbench in my garage, I would use soldered | | | | the industrial supplier likely have everything you |
| copper pipe. Copper pipe won't rust, and there are | | | | need in one location, undoubtedly, they too will |
| more than sufficient adapters available to convert | | | | have the expertise to provide the advice that will |
| from the soldered (sweated) copper to a | | | | not necessarily be available at the other retail |
| thread.If opting for an overhead main, know that | | | | outlets.If you have questions, please don't hesitate |
| the longer the supply line to the application, the | | | | to visit my site and send me an email through the |
| more pressure loss there will be. Each elbow and | | | | contact page there.Bill Wade's experience in |
| every turn creates a loss in available pressure at | | | | compressed air and other industries spans |
| your application, so make the air main as large as | | | | decades; from field sales positions through to the |
| practical. How big? Why not 3"' copper pipe at the | | | | corporate presidential office. His sales agency |
| ceiling and 3/4" copper drop lines for the home | | | | represents a select group of industrial firms. Mr. |
| workshop?Remember that PVC or RVC air hose | | | | |