Air Compressor

Sanders and grinders have a high air requirement. Either a fast compressor or a large tank, with good sense favoring the combination. I use a tube and the lungs to clear insides of turnings, though my 20gallon will do a couple/three minutes of air grinder before it starts to slow.

No way a 3-4gal pancake is going to do it.

For about $379, you can get an upright compressor from Home Depot or Lowe's (made by Campbell-Hausfield) with a 60 gallon tank. It's rated for 6 HP, but it's probably more like 2 or 3 actual HP.

The pancake compressors are just so cute! I looked at several this past summer and was very tempted to buy one. I was looking at a Dewalt/Emglo for about $329.

For about $50 more, I got a real compressor that will handle most anything I want it to do, spray finish and run most air tools. I use a blow gun a lot to clear chips off my lathe or to clear hollow turnings. My compressor runs only occasionally. Much better than one of the little ones kicking on every time I use the blowgun.

The small portable/pancake/stack tank models are primarily intended to power brad guns and nail guns and they do that very well. For much else, you need a bigger compressor. If you are using a mini air grinder, similar to a dental drill, a small compressor could be enough. Just check the tool's air consumption requirements and buy the compressor that you need. It's not a real problem to buy more compressor than you need, but the reverse of that can be a real pain.

Barry

The Husky brand sold by Home Deopt is made by DeVilbiss, which is OK in my book.

Which is why that's what I got.

800+ sq ft of wood flooring later, I'm still happy with it.

Got the 25 gal upright, with the accessory kit for under $300. John Maker of Fine Wood Chips and Sawdust

Don't forget portability.

FWIW, I plumbed an extra Milton quick connect between my 6 gallon PC pancake's pressure switch and regulator. When I need more capacity, I snap in a Rigid 11 gallon tank, the compressor will then charge all 17 gallons of tank to 135 PSI. I keep the portable tank charged. When I need more capacity, I simply plug it in and open the valve. The portable tank will also inflate a lot of tires, shoot plenty of finish nails, etc... and it's always ready to go somewhere else.

This works quite well with blowguns, larger nailers, and small sprayers, like the Critter, without losing much portability.

For completely stationary use, I'd go for one of the oil lubed, 60 gallon, 220 volt units that goes for about $450 at the BORGs.

Barry

I got the Husky brand alright, but I'm almost positive mine is made by Campbell-Hausfield. Their factory is in Leitchfield, KY, about 50 miles away from me. Mine is red. The exact same compressor is sold by Lowe's, but it is blue. I think perhaps one manufacturer will make compressors for several different brands. I looked at a Porter Cable, not sure who makes it. It's compressor was aluminum. Mine is cast iron. That's what sold me, quieter, longer life. I hope, anyway.

Barry

Yes. They are quite portable. They don't take up nearly as much room in the shop either. I had wondered if the small units were large enough for any spray finishing. I have a Binks No. 7 spraygun and wondered if I would be able to use it for small items, like pieces of furniture and turned items. In the end, I decided not to take the chance and went for the larger compressor.

Barry

I suppose it may depend on the model. After I got it, I called Home Depot and asked about mine, who said DeVilbiss made it, and I called DeVilbiss tech support, who took the model and S/N of my unit and confirmed that they made it. After doing 6 years of computer phone support, I like to check out the support for things before I commit to keeping them.

If it was C-H, I would avoid it. I had a C-H HVLP unit literally melt down once. Home Depot replaced it, but that left a bad impression. OK, maybe I'm picky. All right, doggone it, I *am* picky. I'm not rich enough to throw my money away on junk.

Returning to the original poster's question: pancake compressors *are* portable, they *are* relatively inexpensive, but they just don't have enough storage capacity for paint spray or high-volume tools. They are great for jobsite nailers and the like.

I can't give you a simple "get this or get that" answer. Think about how you will use it in the future, and consider the long-term cost. Will you ever spray paint, or other finish? How much space do you have?

I myself opted for the 25 gal upright, because floor space is limited, but I DO spray, and I also planned to use high-volume air tools. But in your case, will life end because you choose a tool that someone else might not? Naw, didn't think so. You could even be creative, like Barry (below) and use add-ons. But you might want the whole schmeer at once. What works best for you?

I think you've gotten a lot different viewpoints and options. My advice is to hunt down a gool deal and get the best buy. Then post a gloat!

John Maker of Fine Wood chips and Sawdust

Barry, is that 60 gal compressor 220v ac???? for me that is an issue as there is only 110v in the garage opps shop. I have wondered the same thing the original poster. Seems to me Home Depot has a 25 gal with accessories for around $300. You know how it is, I won't be useing air tools and 6 months later you are trying them out. Thanks for the info.

Well, it was definitely Campbell-Hausfield that made mine. I double-checked today at lunchtime. The compressor on mine is cast iron instead of aluminum as many of the other brands are. That was a selling point for me.

No, you're not being picky. I don't blame you for avoiding a brand you've had a bad experience with. I have a problem throwing money away, too. I'd rather pay more for something........as long as I actually get more. What actually happened with your earlier unit?

Barry

PS I figure if I get a lemon, I'll just drive up to the Campbell-Hausfield factory and camp out until they make it right! So far I've been well pleased. Of course, my unit probably has < 10 hours on it, too.

Yes, my compressor is 220 volt. For me, that wasn't a problem. Home Depot does have several smaller (but still larger than a pancake) compressors that operate on 110.

Barry

Aluminum cools faster than cast, which is why many compressors and air-cooled engines of all flavors with iron inserts have aluminum cooling fins.

Though it may have been a buy recommendation for you, it does have its drawbacks.

double-checked

I'm not a very heavy user of my air compressor. Regardless of the pro's and con's, it probably won't make a lot of difference in the long run for me. I had noticed that many of the commercial duty compressors had cast iron compressors, if that means anything. Maybe aluminum with cast iron cylinder inserts is the best way to go. Anyway, my compressor is working fine for the time being. I'll just have to wait and see about the longevity angle.

Barry

It's not longevity. I didn't say that. It's efficiency. The reason you want fast cooling is it gets you more compressed air faster. Warm air is less dense, remember? Suck into a warmer cylinder and you start out with less.

you are half right - commercial compressors have an intercooler - makes a huge difference

Ayup. Compressing heats the air - which is why the cooling vanes. Heated air can hold more moisture, but gives it back to you when decompressed.

I've just reviewed the thread and here are a couple of thoughts.

1. Most of the HP ratings you see on retail compressors are "Peak" which is more a measure of the inertia in the motor than a true measure of its power. A motor converts electrical power to mechanical. The maximum electrical power you can get out of a regular outlet is ( if I remember correctly ) about 1.25 HP. Even assuming 100% efficiency ( breaks 3rd law of thermodynamics) you can't have a motor with more than about 1.25 continuous power on a 110V 15A circuit, anything greater is the marketing department skirting the edge of lying.

1. The ratings that you are interested in is the CFM ( cubic feet per minute) at a particular PSI ( pounds per square inch). All the tools have a minmum rating with the same numbers I.E. 8 CFM at 80 PSI. If the compressor's CFM is less than the sum of the CFMs of the tools you use at the SAME time then you will have problems having to wait for the compressor to fill the tank. You need to convert to the same pressure.

I.E. Two tools

a. 6 CFM at 60 PSI; and b. 8 CFM at 120 PSI.

equals

a. 3CFM at 120 PSI; and b. 8CFM at 120 PSI

Total 11 CFM at 120 PSI

If your compressor is rated at less than that then you either use fewer tools or get a bigger compressor.

1. You can get away with adding in a larger tank as long as its big enough and your aveage usage is small enough. Essentially your letting your compressor run for a long time and then using the air relatively quickly. If you then wait for a while the compressor may catch up. Your compressor will take longer to come up to working pressure and wear out faster ( longer duty cycles). Personally I don't think its a good way to go. I use my compressor infrequently but when I do I use it a lot all at once.

1. If you are going to spray you need to get a water separator to get the moisture out.

2. If you are going to use tools you either remember to put a drop of oil in the tool regularly or you get an oiler which adds it to the air.

1. If your doing both 4 and 5 you need to have two separate MARKED hoses since oil in the tool hose is bad for the paint gun. The best idea here is to put the dryer in and then a T junction. One leg leads to the oiler and then a quick connect for the "oiled" line. The other leg goes to a quick connect for your paint line. Don't mix up the hoses or the "clean" hose will be contaminated with oil.

2. For spray painting I have two HVLP setups. One is a 110V compressor that is too small for anything but light usage, 5ft of one side of a 2x6 and you wait about 30 seconds for more air. The other is a 4 stage turbine that works great. The turbine runs on a regular electrical outlet, supplies lots of low pressure air and is easily portable. A compressor based setup would require a trailer, 220V, gas or diesel power to give the same portable performance. One the other hand I would have to use a hammer if I didn't have the compressor.

HVLP = High Volume Low Pressure

Transfer Efficiency is up to double a regular gun and 75-80% of a brush.

TE is basically how much paint started out in the can as compared to how much made it to the object being painted. A brush is close to 100%, HVLP

60-80%, regular high pressure spray gun is 30-40%, high pressure paint pumps are worse than regular spray guns.

TTFN - Frank

Frank's comments are dead on - when buying a compressor, look at flow and PSI, ignore horsepower. He is not right about the 1.25 horsepower IF you allow 220V as well.

Here are two specific compressors I have, to illustrate his point (compare these to the "5 HP" compressors sold at harbor freight or home depot or your local big box hardware store)

1. sears compressor, 2 hp, about 25 years old, 7.3 CFM at 60 psi (this is more than the "5 hp" compressors, in fact it's more than the "8 hp" compressors I've seen). When I used this to paint a car, where it had to deliver at rated capacity for an hour or so, the compressor got hot enough to burn off the paint from the head, and I had to rebuild it because of a cracked ring. I found it could run my small sandblaster for about 20 seconds before the tank would be empty and I'd have to let pressure build up again.

1. my main compressor is a Quincy with a 5 horsepower motor - 19.5 CFM at

160 PSI - two cylinders with an intercooler. It weighs about 400 pounds if I remember right - note that this is a "real" 5 hp, and the compressor is properly sized - the compressor itself is about 24 inches high, 18 inches deep and 18 inches wide and has an oil pump to pressurize the bearings (and an oil pressure gauge as well). Because it has an intercooler, the air is much dryer than I get from the Sears compressor. And, this one can deliver its rated air all day without over heating.

I got the quincy compressor for about $800, rebuilt, from an industrial compressor rebuilder - I'm very happy with it - I'd suggest that you consider a used industrial compressor if you have any need at all for anything more than occasionally blowing up a bicycle tire. I use air sanders on my wood turning, they are much nicer, no heating of the motor, better control, less noise -

snip

You're right about the 220V causing a change in parameters.Note that I said

115V @ 15A which is the "normal" circuit where I live.

My main point there was that the so called HP ratings on most retail machines have weasle phrases like "peak". It allows the mrketing types to claim higher nubers and essentially lie to the consumer without legally lying. If you want to get a true feeling for the size of the motor look at the voltage and the amperage, from that you can get a true estimate of the realpower th motor can deliver.

Your point about the duty cycle of the compressor is good too. Many of the smaller compressors can only be on for part of an hour before they have to cool down. It depends a lot on how hot the incoming air is and how much ventilation the compressor has. Many people try to put the compressor somewhere where it will be "quieter". Unfortunately this tends to mean very bad air circulation, hence more overheating problems. Good air circulation can really help the compressor stay cool.

Regards