Compressor Plumbing in Large Shop

[jkesselr]

Hey guys,

I find myself needing some advice on compressor plumbing. What follows is a long lead-up to a "simple" question.

I have a large home shop (60x140) with 16' eves that is broken into 3 sections - 60x48, 60x72, and 60x20. The 60x48 will be used for automotive service with 2 lifts, one requiring air. The 60x72 will be used for general fabrication and autobody work, and the 60x20 will be used basically as a spray booth. It is generally just me in the shop, but I may occasionally have 2-3 other users. I plan on upgrading my T30 7.5hp 80 gallon compressor to a 7.5-10hp 120 gallon compressor. The compressor will land at the split between the 60x72 and 60x20 sections, meaning it will be roughly 20 feet in from the end wall. I was going to run piping out of the compressor into a few verticals and then through a refrigerated dryer before running it out to the shop. I figure I will burn somewhere in the neighborhood of 60' of pipe just on the verticals. After the refrigerated dryer, I figured I would run the line up to the ceiling down to the automotive service area with a handful of drops, probably about 9 drops around the 60x72, and a few in the 20x60. Near as I can tell, I am looking at about 600'-700' of piping and a bunch of Ts and 90s, with the longest run being about 200-250' (including the vertical "cooler"). Now for the question...

I am looking at the knock-off rapid air kits on amazon that are about $300 for a 300' 3/4" kit. Are these kits sufficient for the air usage/distance of this application? Do you have any advice about these kinds of kits (the good, the bad, and the ugly)? I'd much prefer straight sticks of pex-al-pex, but I can't seem to find it locally, so I am looking at these coil kits. Any suggestions on straightening out the coils?

Okay, so that was more than just a question.

Thanks in advance for any assistance you guys can offer.

John

 

[Spareparts]

I like Copper, I got 1" for the top run and drops like you mentioned, might consider some
drip legs at the bottom of the drops just incase to clear any moisture or debri that collects.
It is going to get expensive any way you do it. Mine has been in service for over 40 yrs. no
problems.

 

[jkesselr]

I was thinking about going copper, but the cost was a big consideration for me. I am afraid to look at what 700' of copper in 3/4 or 1" (or even a mixture of diameters) would cost.

 

[BillK]

I did mine in 3/4" copper with 1/2" drops back in 2000 and it has been trouble free but copper was a lot less back then. I only went about half way up the wall also. I don't see the need to go all the way to the 15' ceiling.

You probably dont need to upgrade your compressor. Most automotive use is pretty low volume intermittant. My 45 year old 7 1/2 hp 2 stage 80 gallon Curtis will keep up with anything I need to do including the bead blast cabinet.

 

[SouthernIllinois]

Biggest thing I learned is find someone / somewhere that sells the pipe locally or ships for free.

I planned to do mine with RapidAir Fast Pipe rigid aluminum piping.

To spread the cost out, I started planning and buying the fittings before the building was even built.

Once it was up, I went to order the actual pipe which came in something like 20' sections. I was floored at what the shipping cost would have been - almost the same as the cost of the pipe.

I then learned a local Mom & Pop auto parts and shop equipment retailer was a TransAir dealer.

Since I also bought my Champion compressor from them, they sold me all the pipe and fittings at a discount, they loaned me the installation kit, and most importantly they delivered the pipe for free.

The ***** there was that RapidAir and TranAir couplers, "T"s and such are not compatible and I was stuck with several hundred dollars of RapidAir fittings I couldn't use. Took me every bit of 9 months to finally sell them at pennies on the dollar. My fault for ordering them without pricing the whole system out including shipping first.

I couldn't be happier with the Transair system - very, very easy to install, I haven't had any issues and leave it pressurized 24/7.

I put about 30+ feet of black pipe, in an up and down configuration, off the compressor then into a Motor Guard TP filter. Each of the three drops has a Motor Guard filter regulator on it. I do not have an electric air dryer and have had no issues with moisture.

Here's a couple pics.

 

[jkesselr]

BIIIK - Thank you for the advice. My only thinking in running the lines at ceiling height was to make service easier, but I guess it is basically the same either way. I am going to have a bunch of pallet racking up and so my thought was getting it above the racking, rather than behind it. I guess I could just unload a shelf if I needed to service anything.

SouthernIllinois - WOW! Thank you for the comprehensive response and for the pics of your gorgeous shop! It looks very well thought out and very well constructed! I will look into your suggestions, as I really don't want the coiled aluminum tubing. No matter how straight you get it, it's never straight and just looks like hell.

 

[Stuart in MN]

It's been a long time since I looked but I think Rapidaire has some design guide manuals available on their website. Somewhere in there should be info on sizing pipe for distance.

 

[no704]

I went copper in my current shop. Absolutely no need to go to roof. I hung 8” of unistrut every third stud about 6’ high. Easily adjusted for drip and ran other stuff on it too.

 

[TurnipTruck]

I am surrounded by the oilfield, so I was able to have five 20’ sticks of 1” galvanized pipe delivered for around $400. I cut and threaded it all myself and ran most of it above the ceiling (under the insulation). I’m not ashamed to say that most of the common pipe fittings were out of the Dumpster (can’t reuse fittings!) so including the air reels and hydraulic hoses I may have $700 total in the whole system.

 

[SouthernIllinois]

It's been a long time since I looked but I think Rapidaire has some design guide manuals available on their website. Somewhere in there should be info on sizing pipe for distance.

There is

Design a Compressed Air System | Air System Builder | RapidAir

Create your own unique air system with our free 3-D drawing tool. You sketch out your layout, and we build out the parts list you need automatically.

www.rapidairproducts.com

Flow Rate Calculator - RapidAir Products

Flow rate calculator contain system specific calculator, general calculator to calculate the products required for your air piping systems.

www.rapidairproducts.com

TransAir does as well

Free Transair System Design

Transair Free System Design and Estimate.

www.transairaluminumpipe.com

Transair Pipe Installation Training

Transair Pipe Installation Training.

www.transairaluminumpipe.com

 

[nadogail]

The volume of all your connected pipe adds to your air storage capacity. It does not take a lot of pipe to equal 5 more gallons of tank.

 

[cvairwerks]

Run the flow and pressure drop numbers on your worst case. You might find the even 1" trunking is too small to support that case. May need to step up a size or two for the trunk line and use the 3/4" or 1" for the drops.

 

[finn]

My shop has a working area consisting of the original 32’x48’ front part, with boiler / compressor room plus a newer 32’x24’ section in the back where the lift and blast cabinet are.

The original shop was plumbed with what looks like 3/4” steel pipe at 8’, and three drops.

I’ve been working in the back with an air hose on the floor, which is less than satisfactory.

Last week I ordered an Amazon 3/4” kit with 100’ of coiled alpex tubing, and fittings for three drops. Also ordered a few spare 90s and a tubing straightener.

As per normal, Amazon has a bazillion vendors selling almost identical kits, some claiming to be Rapid Air, some not. There’s kit I ended up came in an unlabeled brown box, all the parts shown on the site, including a tube cutter, Teflon tape, a reamer to chamfer the tube, set of gloves, but no instructions. At $79 it was the cheapest I found.

The tubing straightener cost the same as the kit and seems to be a quality piece, although the tubing, when hung isn’t as arrow straight as the black pipe.

Mine is at 8’, where the walls transition from painted Osb lowers to ProRib steel uppers.

I’m putting a secondary regulator at the blast cabinets, and hanging a reel with fifty feet of hybrid hose.

I doubt if black pipe would have been any cheaper, or, since I’m working alone, any easier. I think the kit was a good choice, although it will be a few days until I commission it.

 

[72Anthony]

Your unique set up changes things from the typical recommendations for a 2 or 3 car garage. Having up to 3 or 4 users and the sheer size of your shop at 8,400 sq ft.

Is this shop for fun or a business where you are charging clients and paying workers (time is money)? If it's for business, you can probably justify a more robust system.

Considering the size of machine at 7.5 or 10HP I would look at a fully packaged unit. They come with an integrated after cooler, low oil shutdown, and auto tank drain. Its much more plug and play, simplyfying installation.

Since you are painting, you probably want a refrigerated air dryer.

You may warrant a pressure lubricated compressor that is suitable for longer life under heavy load.

I'd also look into something like a Kaiser Air Tower, a rotary screw that has an integrated aftercooler and refrigerated dryer, that is much quieter than a traditional piston compressor. They have a 7.5 HP unit that delivers 28 cfm at 125 psi.

Given the large size of your shop, a full loop of piping may be cost prohibitive.

Larger shops with multiple users can also benefit from additional air tanks located closer to high demand users that can act as a buffer to handle intermittent, but simultaneous users. The extra tanks may allow you to reduce some of the pipe size while still delivering the required flow and pressure.

 

[duneslider]

Just putting this out there. I have used radid air quite a bit at work. It is great to work with in my opinion and we have had zero issues with it. It is a little pricey but cheaper than paying a plumber to do copper. If I can have my guys install it I make more money and we get the job done faster. None of that really matters if you are doing a DIY job other than it is very easy to work with. We use a lot of the maxline stuff, the flexible pipe and it works great for what we do.

I have tried to buy fittings on amazon in a pinch that said they were rapidair brand, they are not. They also don't work, so be very careful about what you buy online, especially from amazon. If you are buying from a real distributor you should be fine. Grainger carries the stuff and there are a lot of grainger locations around. I usually buy direct from rapidair though.

I have used some of the other brands (transair, parker, etc) they are all pretty much the same thing. If you can find someone local that is always nice.

We put in a lot of IR and Kaiser rotary screw compressors, they are great. The customers I have that went with Kaiser seem to be really happy with them, a number of customers seem to complain about the IR compressors. Not sure why exactly, might just be the service with the IR dist isn't as good. If you can afford a screw compressor you will really like it.

 

[jkesselr]

Guys,

Thanks for the wonderful replies! I appreciate the insight. To provide a bit more information in response to some of the posts, the shop is not for business purposes, just weekend warrior stuff. I intend on doing the install myself, so labor costs are not really a factor. I am looking hard at the E-max compressors and, in particular the 10 HP unit in 120 gallon size, to replace my IR T-30 7.5hp 80 gallon unit. The IR works fine, it is just old, secondhand, and noisy as hell! I'd really like to run straight sticks of pex-al-pex, but I can't seem to find a local supplier in the Portland Oregon area, or at least one that isn't going to cost me a fortune.

It sounds like the Amazon kits may be a bad idea, just from the standpoint of future parts availability. I figured the fittings were all pretty standardized with maybe a couple main competitors in terms of style. Does anybody know if the tube dimensions are the same and it is just fitting type that differ?

 

[SouthernIllinois]

I know that RapidAir and TransAir fittings cannot be used on the other.

As far as compressors; I knew I didn’t want a big-box store single stage. I kind of had my heart set on an Emax but couldn’t find a local retailer.

A friend that owns a local bodyshop told me a local Mom & Pop auto parts store also sold commercial shop equipment including compressors.

Come to find out they weren’t only a Champion dealer, they were also a Champion service and warranty provider. That kind of sold me. If I have a problem I can talk to Larry who is 17 miles down the road instead of “Bob” in Pakistan.

As part of the purchase, they ran it in their shop for break-in and to check for any problems and delivered it and set it where I wanted it.

My point is IMHO, shop local

 

[jkesselr]

Sage advice. My only issue is trying to find a good mom 'n pop shop in the People's Republic of Portland. I'll do some more digging locally and see what I can find.

 

[racecougar]

Rolling out Maxline is not nearly as difficult as you're making it out to be. I've done two buildings now, by myself, just by rolling it out on the floor and making final adjustments by hand on the wall. You can see some of it in this photo. One additional benefit over the rigid Fastpipe is that you can make bends at the corners; you're not forced to use fittings at every corner.

 

[finn]

Rolling out Maxline is not nearly as difficult as you're making it out to be. I've done two buildings now, by myself, just by rolling it out on the floor and making final adjustments by hand on the wall. You can see some of it in this photo. One additional benefit over the rigid Fastpipe is that you can make bends at the corners; you're not forced to use fittings at every corner.

Fewer coupling connections, and, if you buy the right straightening tool, it’s advertised as being good for tubing as small as 3/16” od.

I drafted my wife to help run the 3/4” tubing through the straightening tool, but in the end, she mostly watched. I only had the 100’ roll, though. Probably more difficult with a longer run, although nothing says you can’t just cut a chunk to make handling easier, although that certainly increases waste.

 

[kwb]

With the compressor in the middle and maybe 3 person shop even at the length of your building I doubt you would ever get starved for air with a 3/4" pipe system.

I did a number of years in an industrial factory and we fed a lot of employees with air to high demand tools running near consistently on 1in pipe. Problems with air volume were always with hoses getting daisy chained never the piping. We also maintained a fairly low pressure in the system (95psi) for energy costs.

Upsizing to bigger might help in that 0.05% of the time where demand is at a peak. I would be more concerned about the compressor keeping up than pipe losses.

One crutch you can do is to put a small tank at each end of the runs and they can effectively shorten the line length to the tool in use.

 

[PoorUB]

I did a number of years in an industrial factory and we fed a lot of employees with air to high demand tools running near consistently on 1in pipe. Problems with air volume were always with hoses getting daisy chained never the piping. We also maintained a fairly low pressure in the system (95psi) for energy costs.

I worked at a CNC machine shop that used a lot of air. We had two 10 HP compressors we would rotate, but some jobs one wouldn't keep up so we would run the second. We had a 2" main air line and at the other end we put a pressure gauge. When we used a lot of air that gauge would read 20 PSI lower. We finally hung a 200 gallon air tank on the other end of the shop to take some of the "surge" away. They expanded and bought a larger screw compressor and that did the job a long with adding a second 2" main in a loop system.

 

[kwb]

Large dedicated NC centers or other fixed machines are a lot different than hand held tools and have to be treated differently. Over on the paint side of the factory we managed air a lot differently when automated equipment was in play.
I was trying to stick to the realm of the scope of the GJ even at the extreme end that is the OP's shop.

 

[jkesselr]

Great responses, guys! I'm sorry I was MIA for a few days, but came back to more fantastic responses! It sounds like I am overthinking this a bit. A good straightener, or even just rolling it on the floor like suggested, could help with this situation and might be the best approach. That seems like a great inexpensive way to address this issue. It also sounds like 3/4 is more than enough.

On a related note, I know people often do smaller diameter drops, but I don't know that that is possible with these amazon kits. Is there any drawback to running 3/4" main line AND drops? I am thinking it would then be reduced to 1/2" or 3/8" to run through regulators. Thoughts?

 

[racecougar]

On a related note, I know people often do smaller diameter drops, but I don't know that that is possible with these amazon kits. Is there any drawback to running 3/4" main line AND drops? I am thinking it would then be reduced to 1/2" or 3/8" to run through regulators. Thoughts?

All of my drops are 3/4". It may cost a fraction more in material/fittings, but no issues from doing so.

 

[finn]

Great responses, guys! I'm sorry I was MIA for a few days, but came back to more fantastic responses! It sounds like I am overthinking this a bit. A good straightener, or even just rolling it on the floor like suggested, could help with this situation and might be the best approach. That seems like a great inexpensive way to address this issue. It also sounds like 3/4 is more than enough.

On a related note, I know people often do smaller diameter drops, but I don't know that that is possible with these amazon kits. Is there any drawback to running 3/4" main line AND drops? I am thinking it would then be reduced to 1/2" or 3/8" to run through regulators. Thoughts?

My drops are 3/4”, but the terminal blocks on my Amazon kits are 1/2 inch, so a common1/2 inch pipe elbow and ****** can be run to a filter / regulator. Otherwise, just bush it down to a common 1/4” pipe female air coupling and mount the regulator on the blast cabinet or wall and use a hose whip. I think the whips are available in 1/2” also.

 

[jkesselr]

Awesome! Thanks guys!

 

[phred]

I used rapid air in my first shop and really liked it. The fitting get expensive so good planning will save you some money. My second shop I used 1” black pipe for all the long runs and rapid air for the drops.

 

[SouthernIllinois]

Great responses, guys! I'm sorry I was MIA for a few days, but came back to more fantastic responses! It sounds like I am overthinking this a bit. A good straightener, or even just rolling it on the floor like suggested, could help with this situation and might be the best approach. That seems like a great inexpensive way to address this issue. It also sounds like 3/4 is more than enough.

On a related note, I know people often do smaller diameter drops, but I don't know that that is possible with these amazon kits. Is there any drawback to running 3/4" main line AND drops? I am thinking it would then be reduced to 1/2" or 3/8" to run through regulators. Thoughts?

All mine are 1" pipe - the loop around ceiling and the drops to filter/regulators.

 

[PoorUB]

Awesome! Thanks guys!

I like using this chart, https://www.engineeringtoolbox.com/air-line-pipe-sizes-d_1522.html It is based on 100 PSI which is what most air tools are designed for. If you use 175 it will be very conservative. It shows that 3/4" pipe is good for 40 CFM at 75 feet.

Another thing to be aware of is some if these air line kits might be advertised as 3/4" but it is the outside dimension, not the Inside dimension, so their 3/4" is closer to 5/8" inside diameter. https://www.rapidairproducts.com/technical-faq/flow-rate-calculator shows the actual inside dimensions.

 

[TRWham]

...

Another thing to be aware of is some if these air line kits might be advertised as 3/4" but it is the outside dimension, not the Inside dimension, so their 3/4" is closer to 5/8" inside diameter. https://www.rapidairproducts.com/technical-faq/flow-rate-calculator shows the actual inside dimensions.

One of life's little quirks is that pipe is measured by ID, but tube by OD. The same size copper is known by different names depending on whether it is tube for HVAC or pipe for plumbing.

 

[jkesselr]

That is a good point. I don't know what the amazon kits are, but I am guessing it is an OD measurement. I'll take a look at the air line pipe size charts as well.

Thanks!

 

[finn]

That is a good point. I don't know what the amazon kits are, but I am guessing it is an OD measurement. I'll take a look at the air line pipe size charts as well.

Thanks!

I finally finished the installation of my Amazon 3/4” air plumbing kit. I bought the cheapest 3/4 kit, with 100’ of blue aluminum reinforced tubing, a cutter, reamer, three drops/outlets, a few tees, 90degree elbows, and various adapters. It also included a cheesy pair of gloves ( I used my own to turn the reamer), and a roll of teflon tape.

I plumbed it into the 3/4” black pipe I had in my shop already.

From memory, the kit was either $69.99 or 79.99, a twenty to thirty (and up) dollar lower price than most others.

I also ordered an extra Tee and more elbows, as well as a tube straightener for, I think, $70.

The kit went together easily, although there were absolutely no instructions in the box and no labeling. Just a plain brown box, although it was packed exactly, as best I can tell, the same as the MaxAir kit costing double what I paid. There are dozens of YouTube videos on installation of these kits. Some are a little inane. There’s no need to use both Teflon tape and pipe sealant on the joints. I started that way, but realized it was stupid, so finished with just Teflon pipe sealant.

The kit supplied fittings were of a wedge lock / collet design. The extras I ordered were of o ring design. Both interchanged and fit the tubing well. The only leak I had was from a drain I left open when I pressurized the system. Scared me, but a quarter turn on the lever and it ‘s ok.

I spent a couple hours sandblasting toddy with no trauma or issues.

Takeaways: the cheap kit is either exactly the same or a close copy of the higher priced kits.

Those saying the fittings don’t interchange are flat wrong.

The kit goes together easily. I had my wife help uncoiling the long run, but that wasn’t necessary. Otherwise I did the whole thing myself, and I’m an old guy.

Probably the hardest part is chamfering the cut end. Use gloves, as the tool is tough on the hands. The more square the cut, the easier it is to get a nice chamfer. Extra pressure didn’t seem to make chamfering easier, although there is a minimum to get the tool to cut. For shorter pieces, it helps to wrap the tubing in a rag and lightly clamp it in the pipe jaws of your vice.

 

[jkesselr]

Fantastic reply! Thank you so much! This gives me a good bit of insight into the route I am thinking of going.

 

[macdabs]

I used the rapid Air kit in my 40x80 shop red iron . Drops are all at the bays coming down the beams every 20’ . To keep them straight and protect them use electrical conduit EMT . You can also use it to straighten the pipe as you un roll it . I could shoot a pic if needed. I have other shops with black iron and the rapid air is less work and cost is about the same in he end ,

 

[threepiece]

I’m not ashamed to say that most of the common pipe fittings were out of the Dumpster (can’t reuse fittings!) so including the air reels and hydraulic hoses I may have $700 total in the whole system.

You should not be ashamed. Whoever threw the parts out should be.
I have the makings of a complete air system stored away for use in my future shop. All purchased at .20 cents per pound from the scrap yard.

Included is all the 1/2” and 3/4” piping all fittings. ball valves Unistrut, hangers, pressure regulators and a choice of DeVillbiss, Champion, or Salor Beal air compressors all had from the scrap yard.

I recommend visiting any scrap yard that allows sale to the public. It’s like Christmas morning every time I go.

 

[dudley123]

Just rigged up Maxair/Rapidair as well. 3/4" kit w/150ft of line, 3 drops with 2 of those going into hose reels. One thing I want to do is a dedicated drop for the Vapor blast cabinet.

 

[jkesselr]

I used the rapid Air kit in my 40x80 shop red iron . Drops are all at the bays coming down the beams every 20’ . To keep them straight and protect them use electrical conduit EMT . You can also use it to straighten the pipe as you un roll it . I could shoot a pic if needed. I have other shops with black iron and the rapid air is less work and cost is about the same in he end ,

Great information! Thank you for this. I hadn't thought about running it in conduit.

 

[jkesselr]

Just rigged up Maxair/Rapidair as well. 3/4" kit w/150ft of line, 3 drops with 2 of those going into hose reels. One thing I want to do is a dedicated drop for the Vapor blast cabinet.

I, too, am looking at running hose reels and want dedicated lines for certain workstations, like blast cabinet, tire machine, etc.

 

[jblnut]

I have my shop plumbed with a 22mm Festo brand loop around the top up at 18’ and blue 14mm Festo air lines drops every so often. I used to work with Lely robotic milkers and put my system together with leftovers from installs. Look up what a 22mm 90 costs lol.

I have a 30gal tank in the attic above the farthest point from the compressor to add storage and level things out. It fills and drains from the bottom so it always drains out if moisture were to build up.

My compressor is in my loft and I have a drain line hooked to it that discharges into my shop sink. I crack the valve once in a while by the sink and a few drops usually come out.