Compressed air distribution kit--any good?

[Ron Jones near Indy]

I found this on page 91 of Harbor Freight catalog 169-B. It is to be used in place of copper or black pipe when installing compressed air in the garage (shop to me). Do you have knowledge of this or similar systems? The Harbor Freight link is:
http://www.harborfreight.com/cpi/cta...emnumber=66747

[Bob Borzelleri]

I looked at it at HF. Couldn't get past the sense that it wouldn't last very long. Ended up doing black iron pipe. I did get a pipe threader out of the process.

[John Coloccia]

Gee, that hose looks awfully small. Do you plan on doing anything other than blowing or maybe powering a piston? If you're running lots of CFM (like drills, for example), I would want large diameters running around.

[Bill Brady]

We use these fittings on al types of machinery. There is no problem wirh leaking and it is very easy to install. The tubing size may be the only problem, If it is 1/2" it should be big enough.

[Stephen Saar]

I'm actually just getting close to finishing up my shop, and the system that HF uses looks very similar to this system

http://www.rapidairproducts.com/rapidair.asp

Not sure if I'm going to go with either of these systems yet though. I would like to run something bigger than 1/2". Maybe 3/4, 1 inch pipe.

-Stephen

[Callan Campbell]

The tubing seems to be under 1/2" in diameter from the size of the couplers compared to the actual tubing when you look at the link. My guess is around 3/8" or 10mm. Ok for small nailers, staplers and any other low consumption air tools. You'd really like to stay at 1/2" or better for your main air line, and leave dropping a diameter or making a restriction from smaller piping/tubing until the end of your run at a filter-regulator. Second problem is the valve or manifold blocks. If they're tapped and threaded for 1/4", THAT is your new actual tubing diameter , esp if it's way upstream of your end of hose/tool. Once you drop the pipe/tubing size like that, you're supposed to lower the rating of the air line to that smaller, restriction. Basically, you now have a rated 1/4" diameter instead of anything larger that you started out with upstream of that small port.
I too have used that style of fittings, they can be well made, or poorly, like any other air fitting.
Black iron pipe works well, the elbows or fittings that you use to turn corners or change directions also flow air well since the inner diameter is smooth and large. You lose that with using too small of copper tubing since its 90 degree fitting elbows are small and a restriction from the get-go. The rule of thumb for air lines is to "over-build", allow for pipe losses due to any 90 or 45 degree turns and long runs, esp if the pipe is not a loop that ends up back at your air tank[very common in industrial systems]. The losses add up, and are a killer when the line is long and the pipe or tubing that was used is too small.
If you do use copper, then use 3/4" tubing for as much of the main line as possible, then drop to 1/2" as needed. Most FRLs[filter, regulator, lubricators] that are well ported/CFM rated for our needs come with 1/2" pipe threads built-in. If you chose to buy cheaper versions that have 3/8" NPT ports instead, you start to choke your future, larger air tool purchases. You can always buy a larger air compressor, with more capacity, and if you already have that "over-built" air distribution pipe installed, you don't have to change it to play catch-up with your higher output compressor.
Kind of like installing enough outlets for a shop ahead of time. Hard to do, but so worth it.

[Michael Koch]

I bought this system that you are looking at. It is the same system as Rapid air, except that the connectors are terrible. I kept the manifolds and hose and bought everything else from Rapid Air. My advise is to stay away from this product. The rapid air system is very good and works great in my shop..MK

[Joel Earl]

pretty simple and easy to use 1/2" or maybe if you really sense the need 3/4" copper pipe. I've always had just 1/2" lines - right now I have them all across shop and garage circling 3 of 4 walls w/ drops. Can't imagaine why 3/4" would be needed myself?

[Callan Campbell]

pretty simple and easy to use 1/2" or maybe if you really sense the need 3/4" copper pipe. I've always had just 1/2" lines - right now I have them all across shop and garage circling 3 of 4 walls w/ drops. Can't imagaine why 3/4" would be needed myself?

I agree with you Joel to a certain level only, my point was regarding IF you need more air flow in the future, like from buying a larger tool than you had before. And, it needs more CFM to get the job done correctly. If you have hungry sanders or grinders, then Short runs or minimum 90 bends while you're using 1/2" copper work fine, maybe . Long runs and multiple bends/fittings still work ok IF your air tools are low on air consumption. Not if the tool pulls alot of CFMs for its work. You already have a 1/4" restriction in the form of the air nipple or coupler on your air hose and the tool itself unless you're using larger than standard 1/4" air couplers and nipples. Add 25 or 50 foot of air hose, sometimes 3/8" ID, sometimes only 1/4", and you're not getting enough air through all of that with higher capacity tools esp. if the main piping was undersized to being with or at least borderline.
High grade Impact Guns often recommend a 3/8" coupler and 3/8" 25 foot air hose in their manuals to prevent the air tool from being starved of air. And that's just a tool that you're not "on" with constantly like a grinder or sander might be. You'd be suprised at the small details that make an air tool go from working ok to working great. The impact gun roars for anyone, but doesn't deliver full torque unless it has correct volume and pressure to begin with.
Once you have that larger main line installed, you're creating more volume in the system for the tool to pull from. Kind of like increasing your tank size at the compressor. Engineers take each bend or turn in a system and add length to the over-all pipe run based on how many 90's or 45's you've installed. If it's working you , great, I'm totally glad to hear it. I've seen some commercial and industrial work installed really wrong or incorrectly over the years, so I only want to help people prevent that from happen in their shop, even with the smaller scale/ tools that we're working with.