In Need of Air Compressor Wisdom

[MNiceGuy]

I've been in the process of getting my garage set up do projects in. I just bought an Ingersoll Rand compressor with the hopes of being able to run some air tools in the near future.

I chose this particular model:
https://ingersollrandcompressedair.com/p1.5iu-a9-single-stage-air-compressor.html

Previous to this, I had an oil-less California Air that I connected a spray nozzle directly to. That's all I ever attempted to do with it. With this new one, I'm a little confused at what I all need in order to start operating tools.

I gather I am going to want a filter/lubricator. I notice 3/8"NPT is much more common than 1/4"NPT (the native output of the new compressor) for these. Would it be preferable to adapt to 3/8 or stick with the 1/4?

If I want to spray clean air, is there a switch or other mechanism to bypass the lubricator?

For the hose, I'm seeing a lot of threads talking about using 3/8" with 1/4"HF fittings for the best balance of performance and ease of use. Is my thinking correct that even with 1/4" output on the machine and the fittings, the 3/8 will still yield better performance than 1/4 hose?

Any advice is more than welcomed! Thanks!

 

[rlitman]

First, nice compressor. I have that exact one at work, and it's pretty quiet for it's class. It's top heavy, so be careful when you roll it around.

Forget a lubricator. They serve no good purpose except ruining hoses. If you have a fixed tool that needs permanent lubrication, attach it directly to the device. That's what I have on my air hoist and paint shaker. Otherwise just put a few drops of oil into the tool inlet before heavy use.

Typical 3/8" ID hoses have 1/4NPT make ends. How much performance you need depends on what tools you're using, but a normal 1/4" quick disconnect at the far end of a single hose shouldn't cause you much concern. However, once your air circuit includes multiple QDs, you may start to have issues.

 

[K'ledgeBldr]

I concur- run your air through a separator/dryer. oil the tool before use- don't use an oiler. Not only do they destroy hoses, but inevitably there will be a mistake with a hose that had oil go through it and you were spray painting (ask me how I know)!

If you are going to permanently place the compressor- try and put it on an exterior wall, run the intake to the exterior and add Solberg silencer/filters. Mount a hose reel to the wall- call it done.

 

[Ben Buck]

Best to refrain from using extension cords to power it.

Use a dedicated circuit for it. If you have to use a cord- use the heaviest gauge possible.

Take the air to the job- not the compressor.

 

[CraigStu]

I just got a similar Craftsman compressor. The instructions talk about a 120V/15Amp circuit. But they say if you keep popping the breaker go w/ 20amp. So I ran a new outlet w/ 12 gauge romex (vs 14Gauge for 15amp). Lowes or HD has all the stuff you need. The outlet itself is differentiated from a 15 amp by the extra little slot.
15A outlet

https://www.lowes.com/pd/Eaton-White-15-Amp-Duplex-Outlet-Residential-Outlet/1001438608?cm_mmc=shp-_-c-_-prd-_-elc-_-bng-_-LIA_ELC_205_Wiring-Devices-Extension-Cords-_-1001438608-_-Online-_-0-_-0&msclkid=e27fc9ca270c14b655e9a8053be0407c&gclid=e27fc9ca270c14b655e9a8053be0407c&gclsrc=3p.ds

20A outlet

https://www.lowes.com/pd/Eaton-White-20-Amp-Duplex-Outlet-Commercial-Outlet/1001438664

I agree, skip the oiler. Get a small can of oil w/ small nozzle on it and put a drop or two in the air tool when you remember to.

Advance Auto Parts - Down for Maintenance

5 years from now you will still be using this bottle.

 

[Metal-Marc]

Long links are long.

 

[toyotadriver]

I wouldn't use a lubricator. Those are for dedicated lines on dedicated tools. The average homeowner doesn't need a lubricator and as mentioned, it destroys hoses for any other use.

I have and love my hose reels. Use them all the time. Have them mounted to the bottom of my trusses in my shop.

 

[rayra]

The tool and hose fittings are all usually 1/4" ID, that's pretty much your flow restriction if things are necked down to that anywhere along the run from tank to tool. So it doesn't much matter.

Use as few right-angle elbow fittings as you can, same as with water lines. Every hard turn reduces flow rate. Doesn't matter as much with air, but fluid dynamics is still a thing.

OIl the tool, not the line.

 

[u2slow]

Something to note is that 1/4" NPT has a larger ID that 1/4" M fittings (weird, I know, but its true).

If you plan to run a heavy-duty impact gun (or other high-demand tools), I know from experience you may want the V, P, or T style fittings. One advantage to V style is some couplers are universal and can use M style ******* (male ends).

Hoses are normally manufactured such that the fittings are one size smaller than the hose ID. (i.e. 3/8" hose has 1/4" NPT ends). Also, a long hose of small diameter reduces your flow and pressure. The common 50' 3/8" hose retractable hose reel is a common bottleneck.

 

[CraigStu]

I ran into this

Something to note is that 1/4" NPT has a larger ID that 1/4" M fittings (weird, I know, but its true).

If you plan to run a heavy-duty impact gun (or other high-demand tools), I know from experience you may want the V, P, or T style fittings. One advantage to V style is some couplers are universal and can use M style ******* (male ends).

Hoses are normally manufactured such that the fittings are one size smaller than the hose ID. (i.e. 3/8" hose has 1/4" NPT ends). Also, a long hose of small diameter reduces your flow and pressure. The common 50' 3/8" hose retractable hose reel is a common bottleneck.

I ran into this the other day. I needed to replace the 8yr old rubber hose on one of my reels. Rural King had the Goodyear red hose that seems at or near the top in every review. They had a 3/8x50 and I happened to look into the brass fitting on the end and saw that 1/4" bore. They also had the next size up 1/2 inch hose. That looked really good until I saw the thread size of the brass end. 1/2 inch NPT is huge.

 

[PWC Repair]

If it doesn't have a regulator, you'll need one. I just bought a filter/regulator for my new compressor at Harbor Freight. They are clearancing out the Central Pneumatic stuff. It installs onto the tank, and your quick connect goes onto that. You can also buy high flow 1/4" air hose fittings that are noticeable less restrictive than the regular fittings.

 

[PoorUB]

I agree with no lubricator. Just put a drop of tool oil in your tools every time you use them. A filter/regulator is a good idea.

I have a 3/8" hose reel but also have about 10 feet of 1/4" hose on the end because it is more flexible. If all your are going to do is clip on a 25 foot air hose even 1/4" will work fine for 95% of most home hobbiest type work. If you run longer hoses then 3/8".

As far as quick disconnect fittings all I have are the Milton M style and they work fine for what I need them for so I never jumped all all the hype that you need high flow fittings. Also, what ever you decide to do will probably work out just fine. I feel that way to much thought goes into air tools and line sizes when most guys will never notice the difference!
I found this interesting, he claims there is not much difference in fittings between the standard fittings and hi flow.

 

[u2slow]

They also had the next size up 1/2 inch hose. That looked really good until I saw the thread size of the brass end. 1/2 inch NPT is huge.

My 50' 1/2" hose has 3/8" NPT factory ends.

Most air fittings can be had in 3/8" npt, so you don't a need a mess of reducers.

 

[jkuro]

Get Stedlin air fittings, the best out there. They also offer a Garage Journal discount.

 

[jdm5]

+1 on Stedlin

 

[rburke65]

What is your air consumption of the tools you will be using? That is how you determine the compressor you need.

 

[Stedlin]

The importance of good flow capacity increases as the available system pressure decreases.

A system with good flow capacity enables you to run a lower compressor pressure which results in longer lifetime and more electrical efficiency. Nothing wrong with that.

 

[Snapped-off]

Get Stedlin air fittings, the best out there. They also offer a Garage Journal discount.

Does it work now? The code I tried was invalid.

 

[Stedlin]

Does it work now? The code I tried was invalid.

fullflow
It’s valid.

 

[FredWanaker]

I bought a craftsman compressor (devilbiss) years ago with about those ratings and it could not keep up with painting, heavy tools, glass beading etc., ended up adding a second used one in parallel to get the volume needed. The use determines which compressor to buy. If I had to do it over would have just bought a larger unit. The only nice thing about two compressors, is I can switch on one for light jobs or two for large ones. The pressures are staggered so only one works at the first need for air, and then the other kicks in when the demand is higher. I am not sure that 5.2 CFM at 90 PSI is going to run all the tools you may want to use. Here is a link to common CFM's used. https://www.northerntool.com/shop/tools/buyers-guides_air-compressors .

 

[theoldwizard1]

My nephew had a big sandblasting job. One 2 HP compressor could not keep up. Two 2 HP compressors worked great.

 

[racecougar]

As far as quick disconnect fittings all I have are the Milton M style and they work fine for what I need them for so I never jumped all all the hype that you need high flow fittings. Also, what ever you decide to do will probably work out just fine. I feel that way to much thought goes into air tools and line sizes when most guys will never notice the difference!
I found this interesting, he claims there is not much difference in fittings between the standard fittings and hi flow.

In the same vein, I made these two quick/dirty videos years ago to illustrate the noticeable improvement in switching from a 50' 3/8" hose to a 50' 1/2" hose. The first video utilizes a 50' 3/8" hose with "M" style coupler and "M" style fittings on all tools. The second video utilizes a 50' 1/2" hose, Milton "V" style coupler, Milton "V" style fittings on the first two tools and "M" style fittings on the second two tools. Every little bit helps, but the hose diameter increase provided far more improvement at the tools than the coupler/fitting size increase. Fluid dynamics/friction factor explains this.


Video 1:

Video 2:

 

[MNiceGuy]

Lots of great information here. I either have an answer or a good place to start for all of my questions. Much appreciated!

Right now I'm hoping to run a 3/8" ratchet, air hammer, and possibly a 3/8 impact. For 1/2" I have the Milwaukee cordless which does quite well for itself.

I'm lucky in that I have 20A outlets in the garage but I'm currently in the process of running a dedicated 20A for the compressor (a short and easy run to the panel). I'm using 12ga solid.

I'm really hoping to get into some restoration work starting off with my dad's vintage Yamaha motorcycle. If that doesn't work out then I have a very, very good compressor for airing tires and blowing debris. If I really get into it and enjoy that kind of work then I can always look into something of the 60-80 gallon variety down the road.

 

[FredWanaker]

CFM is more important than tank size. The tank is just a buffer. Once a large tank drains down to a lower pressure it takes all that much longer to fill it again.

 

[u2slow]

@racecougar Lol! I've performed the same tests for myself.

@FredWanaker cfm matters, but so does tank size. You want to start your 'big gun' with the tank at full pressure. If the seized fastener doesn't budge before the comp cuts in, it has basically zero chance of yielding until its pressed up again. If your tank is bigger, it does take longer to fill, but you also get many more hits in before the pressure drops.

 

[Stedlin]

Lots of great information here. I either have an answer or a good place to start for all of my questions. Much appreciated!

Right now I'm hoping to run a 3/8" ratchet, air hammer, and possibly a 3/8 impact. For 1/2" I have the Milwaukee cordless which does quite well for itself.

I'm lucky in that I have 20A outlets in the garage but I'm currently in the process of running a dedicated 20A for the compressor (a short and easy run to the panel). I'm using 12ga solid.

I'm really hoping to get into some restoration work starting off with my dad's vintage Yamaha motorcycle. If that doesn't work out then I have a very, very good compressor for airing tires and blowing debris. If I really get into it and enjoy that kind of work then I can always look into something of the 60-80 gallon variety down the road.

The compressor you bought is only rated to about 5 CFM from 2 HP.
2.5 CFM/HP is very little. I suppose it was to get the sound level down.

 

[PoorUB]

Lots of great information here. I either have an answer or a good place to start for all of my questions. Much appreciated!

Right now I'm hoping to run a 3/8" ratchet, air hammer, and possibly a 3/8 impact. For 1/2" I have the Milwaukee cordless which does quite well for itself.

I'm lucky in that I have 20A outlets in the garage but I'm currently in the process of running a dedicated 20A for the compressor (a short and easy run to the panel). I'm using 12ga solid.

I'm really hoping to get into some restoration work starting off with my dad's vintage Yamaha motorcycle. If that doesn't work out then I have a very, very good compressor for airing tires and blowing debris. If I really get into it and enjoy that kind of work then I can always look into something of the 60-80 gallon variety down the road.

I ran a three man small engine shop off a 3/4HP compressor for a few years. We didn't have any high usage tools like air drill or DA casnders. Just quick blasts from impact wrenches. The 3/8" air ratchet will be an air hog, but as long as you are not removing a lot of bolts it should do fine.

 

[rlitman]

The compressor you bought is only rated to about 5 CFM from 2 HP.
2.5 CFM/HP is very little. I suppose it was to get the sound level down.

Knowing how that unit runs (as I said, I have one at work), my guess is they're seriously under-running the pump to keep it quieter and keep the temperatures down. IR being a company that has a brand reputation to protect, its CFM is also not inflated like most of the numbers on the market, but I do suspect the motor HP is inflated, as 2HP out of a standard outlet is kind of unreasonable. So I'd guess it could really be closer to 3 CFM/HP, but that's kind of a stab in the dark.

Also, while this is a twin-piston, it's not a dual stage, so I wouldn't expect best-in-class performance. My two stage makes 3.27 CFM/HP.

 

[MNiceGuy]

I'll have to check out it's actual CFM later on to see how it stacks up against its claimed 5.2CFM.

While the CFM rating is not going to knock anyone out of their chair, it was one of the few models in this class, locally available, which had a high duty cycle. I looked at the Central Pneumatic, Husky (and its Craftsman clone), and a couple DeWalts. The Husky has higher output but is noisier and only has a 50% duty cycle. While not disclosed directly, I suspect the Central Pneumatic is in the same boat. The DeWalts I could actually get my hands on were oil-less models which I didn't want.

The Ingersoll is rated to 100% duty cycle which I understand is a bit of a gray area. The takeaway is it's designed to run for extended periods of time or many cycles before resting. I chose to take a little less CFM and a smaller tank for the piece of mind if I do end up doing something that calls for extended performance I'm not going to destroy it.

Secondarily, the Ingersoll is built like a tank (excuse the pun) compared to my other options. It's about 50lb heavier than the arguably larger Husky. It really has a feel of quality which I appreciate.

I think it should be plenty to get me going. The main objective was to replace the California Air (2.2CFM) that I was constantly overrunning and waiting on. If I manage to get into something where the same thing happens with the Ingersoll I'll move up to something more stout.

 

[u2slow]

Those of you struggling with needing a portable comp that has some CFM... CH and Speedaire both have ~10cfm/3hp/20gal machines.

You just need to be able to wire a circuit with a 6-20R receptacle. An extension cord isn't difficult to make either, if you need it.

 

[MNiceGuy]

Those of you struggling with needing a portable comp that has some CFM... CH and Speedaire both have ~10cfm/3hp/20gal machines.

You just need to be able to wire a circuit with a 6-20R receptacle. An extension cord isn't difficult to make either, if you need it.

Both of those look pretty good. I did chuckle a little at the CH's claim of "low noise 87dB". Definitely a lot of punch in a small package though.

 

[rlitman]

Both of those look pretty good. I did chuckle a little at the CH's claim of "low noise 87dB". Definitely a lot of punch in a small package though.

It's dead quiet compared to an oilless.

 

[MNiceGuy]

I'm with you there. My first compressor was a bargain bin pancake setup that was so obnoxious the wife even started commenting about it. As long as I never have to endure that again (the compressor) then I'm happy I guess.

 

[Stedlin]

Over 5 years ago I built several prototype air compressors.

One version is two stage with a displacement of 16 CFM driven by a two HP 115V motor.

If I plumb it in a conventional manner with tank check valve it stalls before reaching 80 PSI.

Amazingly, connecting the compressor output with a straight pipe to a 1/2” bore gate valve feeding the tank allows it to pump up to over 200 PSI. The actual air output after accounting for air temperature is about 11 SCFM. This is considerably better than any compressor I am aware of that runs on 115V.

Interesting. Too bad I don’t have time to research this further.

 

[nadogail]

Many people buy a given compressor because of it’s lower price. They failed to match the compressor to the load the they put on it. Most of those wind up being disappointed.
After you find out what size and type of compressor you want you will be a better shopper. It took me three try’s to finally get the best compressor for my present needs.

 

[rlitman]

Many people buy a given compressor because of it’s lower price. They failed to match the compressor to the load the they put on it. Most of those wind up being disappointed.
After you find out what size and type of compressor you want you will be a better shopper. It took me three try’s to finally get the best compressor for my present needs.

I get it. I too am on my third. I had a 120V 30 gallon oilless that served me well, but was just too small. I upgraded to a 240V 60 gallon oilless, because the price was right, but oilless just plain *****. My 80 gallon 7.5 HP beast came from a body shop that closed, but used single phase compressors in that size are hard to find.

 

[MNiceGuy]

Just for fun, I thought I'd check out the actual CFM output of the little Ingersoll last night.

Advertised flow: 5.2CFM @ 90psi (I have seen some etailers list 5.5CFM but the manufacturer shows 5.2CFM)
Observed flow: 6.80CFM

Method:
Cut In Pressure: 100psi
Cut Out Pressure: 132psi
Tank Size: 20gal
Atmospheric Pressure: ~14.85psi (30.29in)
Tubing Volume: 0.0861 gal
Recharge Time: 53s

 

[PoorUB]

Many people buy a given compressor because of it’s lower price. They failed to match the compressor to the load the they put on it. Most of those wind up being disappointed.
After you find out what size and type of compressor you want you will be a better shopper. It took me three try’s to finally get the best compressor for my present needs.

I agree, and aanother thing is we often upgrade because we can finally aford to, not because we have too!

I have the first compressor I had and the second too. The third I sold to my neighbor an would still have it if I had't run accross a used 5 HP 80 gallon Curtis for $100. The 3HP 60 gallon was al I needed for about 90% of the time and wouldn't have updated if I had not run across the deal on the Curtis. For what I sold the 3HP 60 gallon I pretty much broke even on getting the Curtis up and running.

 

[u2slow]

Im on my first compressor still... 3hp/10cfm Speedaire... bought new 22-23 years ago.