compressor advice

[merrill77]

Someday I'd like to upgrade my compressor. I have a little PC pancake, but it is so loud, I rarely plug it in. I'd like to get a larger model and put it out in my garage with a line into the shop. My immediate use would be nailers in the workshop and filling tires, balls, etc for my boys. Eventually I'd like to try spraying finish.

Not knowing much of anything about these things, let's start here: What is the difference between this used compressor and this new one? Why are they in the same price range? How much life should I expect to remain in an old unit like that? How would I evaluate that?

TIA!
C

 

[Rob]

Main difference I see between the two is the cfm, 16 cfm vs 9 cfm. That's what you'll want to look for. Either will do for your purposes. I have one similar to the Husky, Lowes branks, it's 15 years old and still going. That being said, unless the used one is a two stage, IMHO it's over priced.

 

[FredP]

without gettin too technical..... the used speedair will prolly outlast the new husky 5 - 1. do you need 16CFM? prolly not. for the light use you describe the new unit will be more than you will need and you get a warrantee. the speedair is 3 HP. the husky is 3.2 HP RATED. rated and true HP are 2 different animals these days so you realy need to look at the motor specs to determin HP. The sreedair was made here. The husky? prolly not......

 

[scsmith42]

As far as the difference between the two compressors, Rob and Fred make some good points. The Dayton Speedair is an industrial compressor, the Husky is a consumer compressor.

Typically, in terms of durability, I rank products into three categories: Consumer, commercial, and industrial, with industrial being the best.

For the average homeowner though, you don't need an industrial compressor. Even my "big" compressor (27 CFM / 80 gallon tank) is only what I'd call a commercial unit.

An industrial compressor is designed for continuous duty. Yup, that's right, the thing will run for 24 hours a day 7 days a week without complaining. A consumer compressor would probably die after a few hours of continuous operation, because it's not designed for the extra heat load that is encountered by continuous duty.

Commercial units are built similar to industrial, but with a lower duty cycle.

Now, that's probably more than you wanted to know!

If it were me, and I was in the market for a compressor to do the things that you listed, I would seek a 7 -12 CFM single stage unit, probably oil-less, with a 40 - 60 gallon tank. This not only would meet your needs, it would meet most foreseeable future needs as well.

Any major brand should be fine, but I'm partial to Ingersol Rand due to their quality and American manufacture. IR has models that vary from high-end consumer up to industrial. Campbell Hausfeld also makes good consumer and commercial compressors. One nice thing about IR and CH is that you can obtain parts for them, should you ever need them. Getting parts for a BORG compressor might be a bit more difficult. Craftsman also makes great consumer grade compressors with spare parts availability. Many of the compressor manufacturers "play games" with respect to the motor HP, so don't put a tremendous amount of credence into "rated" hp.

Typically you choose your compressor based upon three factors. First, how heavy a unit you need (consumer, commercial or industrial), second, the amount of air storage required, and third the CFM required. In many instances, you can make up for a lower CFM by having more air storage.

Motor size is based upon CFM and PSI, with two-stage compressors requiring larger motors (because they pressurize the tank to 175 psi instead of the usual 120 - 135 for single stage units).

Just about all compressors are loud, however with more CFM the don't have to run as long when they are filling the tank (tank sizes being equal). It's a good idea to install them in a separate room, etc for noise control.

One drawback to buying a compressor that is substantially larger than you need is the power surge required to start it. A 3 hp unit is about right for the average homeowner. 5 hp is ok too, but you'll need to run fairly large wiring in order to supply the necessary startup current.

 

[SteveColes]

I know this is not what you meant, but just in case I'll mention it. I see signs of corrosion and I would not want to buy and air compressor that shows that, especially around the drain ****. Of course you can clean up the whole unti like any other tool. But what you can't see is what the inside of the tank looks like. And you certainly can't clean it up. MTCW

 

[DaveD]

Are there oiless compressors that don't make that awful noise? Don't they all 'scream'?

I thought you had to get the 'old fashioned' compressors that have the oil bath crankcase that run about 1100 rpm or less to have a 'relatively' quiet unit.

As for a old commercial tank I would say that even after 10-15 years the tank is not really corroded on the inside. I had occasion to cut up a vertical 80 gallon tank that came out of a Toyota dealership (run hard for years) and although it had 1/8" of sludge on the sidewalls and probably 1" caked in the bottom the steel tank itself was not corroded.

I'd probably take the used one for $400 if he would sell it for that although its overkill for what you want to currently use it for.

Air supply/volume is like cubic inches in a motor. 'the only substitute for cubic inches is more cubic inches' :gar-Bi:gar-Bi:gar-Bi

Oh yeah, find out how old that used one is. I'm pretty sure there is a metal tag welded on it somewhere that has date of manufacture and all the particulars of its pressure capability. Also be sure that motor isn't a 3 phase motor (probably isn't). Also see if you can test it out and see if it will build pressure and hold it. The pump is expensive to replace.

 

[Charles Lent]

Once you have a big compressor you will discover all kinds of uses for high pressure air, and you will be very happy with what you had thought was a "too big" compressor. I bought an 18 cfm about 5 years ago, thinking that it was too big for my needs. Now I sometimes wish that I had bought a bigger one.

Charley

 

[merrill77]

Thanks for the detailed response! No, it's not more than I wanted to hear at all. I'm a bit torn on this, because I'd like this to be my _last_ compressor purchase...but I also don't need it to live another 50 yrs beyond that :>

If it were me, and I was in the market for a compressor to do the things that
you listed, I would seek a 7 -12 CFM single stage unit, probably oil-less,

Why oil-less? I was pretty well convinced (based on previous research) that I should avoid the oil-less units.

 

[FredP]

oil-less has some advantages but the disadvantages are far greater. advantages are no oil to get into the lines. no oil changes. spray finishes dont like motor oil but I've never had this problem because of the set up I have. oil-less are generally lighter weight. I classify them as throwaways. they are also noisy but usually cheaper. oil bath will last much longer and generally are quieter. When it comes to compressors bigger is better provided the CFM is high enough to do what you are wanting to do. your tools will tell you how much you need.:icon_thum some companies exagerate CFM by stating something like 15CFM@40PSI. what you need is ??CFM@90PSI or greater. you can reduce PSI down stream with a regulator for those tools that require less PSI like sprayers and such. I use a splitter in line and a regulater on one of those for spraying and the other carries more PSI for normal uses like nail guns, blowers ect. this way I never have to mess with the regulator at the compressor and dont need one at the spray gun. If you want a copressor to last the rest of your days look into IR, rol-air, speed-air, CH industrial lines. there are others. I tend to stay away from PC, husky, craftsman ect. Emglo used to be good but the newer ones are shall we say not so much? quincy and champion ae also great brands but they aaint gonna be cheap!

 

[scsmith42]

Why oil-less? I was pretty well convinced (based on previous research) that I should avoid the oil-less units.

You mentioned wanting to get into spraying finishes at some point in the future. Conventional (oil lubricated) compressors sometimes deposit a small amount of oil inside the air lines, which can create major problems in a spray finish.

Additionally, over time you may end up with a small amount of oil inside your air lines, so even if you used an oil-less compressor in the future for spraying, you would also need to use clean air lines as well.

Granted there are oil separators available, but it's best to avoid the problem if possible. One of the best spray finishes is from an HVLP setup with a conventional gun that converts high pressure into high volume at the gun. These models tend to flow a lot of air, so if there are oil deposits inside the line the higher air flow is more inclined to pick up the oil residue.

Oil less compressors have come a long way, and are a good choice for light duty use (which is basically the applications that you listed).

For heavier duty use, yes an oil lubricated compressor is a better way to go, and if you are purchasing the "compressor of a lifetime" oil lube would probably be a better choice. Decisions for oil lube included splash versus pressure lubrication (the latter being better). Addtionally, you can decide between alumimun or cast-iron material for the compressor and head (with CI being the more durable choice).

What type of budget do you have? Northern Tool has an 18 cfm IR oil lube for a little under $900.00, and a 10.3 cfm version for $630.00, both 60 gallon tanks.

Sears has a Craftsman Professional model, 60 gallon oil-free 9 cfm for $617.00. Sears also has an 80 gallon, 2-stage cast iron pump oil lube model with 13 cfm for $950.00. Other than a low CFM, that's a lot of compressor for the money.

Since we're talking more serious compressors, one major advantage of a two stage model is that the tank pressure is usually 175 psi - about 40 psi greater than a single stage model. Compressed air volume is not linear - the higher the PSI the greater the volume of air that is compressed into the tank.

Lots to mull over, eh?!

 

[DonnellyJT]

If you go with a consumer grade....avoid direct drive units. Make sure it has a motor and a belt. Direct drive are extremely loud and will vibrate even a concrete floor to the point that it will shake the house.

 

[merrill77]

This IR unit is listed as continuous duty. It's a bit beyond my budget, but not as far out as I expected. Is this what you would consider "industrial"? If so, I assume it would this fall into the "it'll outlive me" category for hobby-shop user?

 

[merrill77]

You mentioned wanting to get into spraying finishes at some point in the future. Conventional (oil lubricated) compressors sometimes deposit a small amount of oil inside the air lines, which can create major problems in a spray finish.

Hmmm...did not know that!

Granted there are oil separators available, but it's best to avoid the problem if possible.

What does that entail? Is it considerable extra investment in the spray equipment?

TIA!
Chris

 

[stave]

I bought a Ingersol Rand at Tractor Supply several years ago for around $500. Has a 60 gal tank, belt driven, don't remember the cfm. I do use it to spray lacquer and paint. I also use a die grinder on occasion along with air hammers with carving gouges to carve. The grinder works it pretty hard using lot of air. I replaced the seals on the head once, parts were easy to get. One other difference between commercial and industrial IG compressors is that a IG technician will not work on the smaller 60 gal units, they will basically work only on the industrial models. I put a filter on the line coming out of the tank for oil and moisture as my air lines are short. Longer lines, espicially in unheated areas will require filters amd drip lines at the end of the supply line to avoid problems if you intend to spray. My philosophy when buying just about everything for my work is to by the best I can afford..even if it is a stretch. Never gone wrong yet. Good luck.

Stave

 

[Rob]

I'm going to disagree with Scott, get an oil compressor, I've used both. while the advantages of spraying with an oil less is great, you'll find that you'll use it for much more then spraying, the noise, and wear and tear on an oil less will drive you nuts. Get an oiled compressor, you'll have to purchase a regulator any ways. So get a regulater/filter set up, about $50 from harbor freight, and you'll be goldent.

 

[scsmith42]

This IR unit is listed as continuous duty. It's a bit beyond my budget, but not as far out as I expected. Is this what you would consider "industrial"? If so, I assume it would this fall into the "it'll outlive me" category for hobby-shop user?

Chris, that IR unit is an EXCELLENT choice. 8000 hours of pump life equals running it for 8 hours a day, 5 days a week for four years solid. The CFM is adequate for just about anything that you'd want to do (with the exception of running a large bead-blasting cabinet), and it's a great balance between price, durability, and performance. A friend of mine has basically the same compressor and really likes it.

The reality is that you will probably operate it for 1 hour or less a week. I would consider that model to be more on the commercial versus the industrial side; although it is rated for continuous duty the pump life is 8000 hours, versus 15,000 or more for the industrial units. NO matter how you look at it, it should "outlive" you so to speak and would be an excellent choice.

I put an hour meter on my big compressor when I purchased it about 11 years ago, and in all that time I only have about 300 hours of operation on it.

Accessories to purchase with it are a high quality filter dryer and a regulator. Additionally, the automatic tank drain valves are a really nice accessory. I typically mount my compressors up on 4 x 4 wooden blocks with rubber gasketing on one side, in order to ease access to the drain valve on the bottom of the tank as well as to isolate the vibration. The tanks are bolted to the concrete slab through the blocks.

 

[Woodman2k]

Chris,
the unit that you linked to is the first unit coming out of the homeowners series and is very popular as a employee purchase unit.It is a single stage but is quieter than a direct drive.I personally like the two stage 5 hp version but it is a considerable jump in money.When you decide to buy and you end up going with a IR unit ask about the warranty options on that unit.I know that on mine I purchased the start up kit which includes maintenance items plus filter and oil,by buying the kit at purchase it doubled the warranty for free.I don't believe they offer that for all units but it would be worth asking.

I by the way work at IR,and unfortunately they recently changed the employee purchase plan so you can only buy one unit at a time.I wish we had done that group purchase earlier this year.Anyway,if I can help you in any way let me know.Also,getting the oil out of the air is a tougher task with a cheaper compressor because of the poor tolerances that those units are built to.
Thanx,Greg