Air Compressors

[kmcconaughey]

What about flakes in a forum?

 

[kweaver]

Kendell's just sitting there letting me squirm !

 

[aaytay]

Not to get back to the subject or anything (I know, shame on me!) but all this talk about galvanize/rust flakes inside the air lines are EXACLTY why I used copper to run the air lines from my compressor. Sure it cost more, but I already spend "way too much" (her words!) on the compressor, what's the point of trying to save a buck on the lines to run the air.

('Course, all this said, all of the air lines in my garage are relatively short runs.)

 

[kmcconaughey]

All the air lines from my compressor are still just hose, if I ever decide to run plumbed lines, (which could happen sometime after I finish my Original refurb, shut up Art!

), I'll likely use copper as I stated back in 2004:

<blockquote><hr size=0><!-quote-!><font size=1>quote:</font>

Thursday, March 11, 2004 - 02:30 pm:

With my wimpy 10'x18' shed it wouldn't take much to plumb it. If/when I plumb it I think I'll go for the copper tubing. I like working with solder. )

Thanks for all the input.<!-/quote-!><hr size=0></blockquote>

 

[kweaver]

Art - With scrap copper a month ago here going for $2.50 a pound I wouldn't tell everyone There's been several AC units and power lines stolen around here !

Price of meth must be going up ...

 

[kmcconaughey]

KENtucky, it's been in the news here too. Lots of copper pipes and wires disappearing from homes (those that have been foreclosed on with no one living in them) and from construction sites.

 

[lbaker]

I routed 3/4 pvc along the top edge of wall and ran my air hose thru it. Cheaper and looks good.

 

[aaytay]

Ken-
Yea, the price of steel is nuts too. How long until they start cutting up bridges and selling them? (More meth!)

I "tried" to order a 12' long stick of 2"X3" tubing (3/16" thickness) for a possible project, but when I found out it would have cost me $130+ just for that one stick of metal I put the brakes on that project REAL quick!

They sell the stuff by the inch!!!

 

[kide]

KentucK (answering the question from the morning..):
Wasn't me having rust plug things up - as I said the only place I see it is in the first separator on the first station (I run 'em both sides of every regulator, because of the cooling effect of expansion in the regulator).. I am pretty fussy about the air, 'cause the plasma cutter likes it <u>dry</u> ! - It eats up consumables (must be why they call 'em that) when you get moisture and would plug the nozzle if you had FOD..
I'd never run black plastic - things get nicked around here too easily (Graeme: as in cut, not stolen.. )

 

[kweaver]

Where was it that you guys were talking about air plumbing with copper , pvc , black pipe ...

anyway here's good info on the 3 grades of copper
K-L-M

 

[dross]

I bookmarked the page that discussion came from, cool reading.

 

[kweaver]

There's a link there for a 66 page pdf file of copper tube handbook

 

[jchamberlin]

Guys, I've read this thread twice, and another one on the same topic elsewhere forum: my take-away was to "get the job done" I would need a unit that is capable of delivering at least 10 CFM, especially if I ever wanted to do any painting or sand-blasting.

This Christmas I've gotten the whole family pulling to get me a new air compressor: the one I have is worn out. I want to recommend a worthy purchase. I'm even willing to match what the family is offering in order to get myself into a unit that they can afford and with which I can "live happily ever after."

My dilemma is as follows:

(1) I can get a single stage air compressor employing a 3.5 HP motor delivering 10.3 CFM at 90 psi with a 60 gallon tank ("assembled in Rockhill, SC") from NAPA Air Compressors, what is termed an "Air Boss" air compressor, Cost $750

(2) A 5 HP unit from Ingersoll-Rand available from Tractor Supply which delivers 16.5 CFM at 90 psi also with a 60 gallon tank --but it is a 2-stage unit. It is on sale for $999.00. (A 3 HP I-R unit w/60 gal. tank is regularly $850).

So it sounds like the Ingersoll-Rand 2-stage is a great deal and I'm ready to recommend it to the family, but I hesitate. I don't feel I know all the pros & cons.

The Ingersoll-Rand unit seems to compare to the NAPA "Performance" line which employs in-line cylinder configuration; their manual recommends an air dryer installed downstream of the air compressor.

Part of what's puzzling me is that an 3 HP I-R unit has two large in-line cylinders and appears to be single stage; the I-R 5 HP "Professional Shop" is a 2-stage unit, but one cylinder appears to be a bit smaller than the other.

What is giving me pause is that I don't really know what a 2-stage unit will mean in practical application. I looked at the "Industrial --Fully Packaged" units from NAPA at 5 HP that cost $2,300. The industrial unit is rated at 16 CFM at 175 psi and employs a magnetic starter. It only turns 600 RPM; the "Air Boss" turns 1200 RPM or more. I don't know how fast the I-R or the "Performa" turn, but I suspect they are both in the 1200 RPM range.

I'm sure they are both less noisy than the oil-less pump I once owned.

I would love to get a unit delivering 10 CFM at 90 psi turning 600 RPM (low noise) that would not require a magnetic starter or an air dryer. I don't really care about the 2-stage part; or more accurately, I don't really know what I'm getting into. Does the 2-stage really deliver more --is it worth it-- or should I content myself with a single stage unit because there is less maintenance and/or performance issues involved?

Or should I just buy the most air compressor I can buy with the money available?

Interested in your thoughts.

 

[dross]

Jeremiah, I think I've heard a 1/4 inch nozzle on a small sand blaster will use 12 cfpm. If your going to paint or use it on a sand blaster an air dryer of some sort is not a bad idea.

 

[wshytle]

Jeremiah-

Here's my main air source I bought back in '07. The model number is CPLC7060V-1. I got it online from CPO (if I remember correctly) but most Porter-Cable dealers could get it. You might be able to order it through Lowes as well. I paid less than $450 delivered by large truck to the end of my drive where I was waiting with my truck. It is a 240 volt compressor and has a 3hp motor. It's all the air I need for anything I need it for. I also have a 30 gallon compressor tank I put in line making it a 90 gallon capacity system. I installed it in the basement to suppress the sound and I really like the set-up.

I think you would be happy with this compressor. I've sandblasted, painted, and use it with air tools all of the time. It has not given any problems at all.

 

[dfrisk]

JEREMIAH - Don't think about this too hard.... Just buy the 5 HP I-R. $999 is a good price on that compressor. And use the I-R synthetic oil in it too, they extend the warranty to 2 yrs from the normal 1 yr period. And yes, the primary or low pressure first stage cylinder is larger than the secondary cylinder.

DAVE - I think it's a 1/8th inch hole flows 12 CFM @ 90 PSI.

I tried to find a link to my Porter-Cable compressor but Black & Decker, now P-C's owner must not be keeping up P-C's website. But I got the full 7-1/2 HP 80 gal. 2-stage compressor, think it something like 26.5 CFM @ 90 PSI. It had better outlet location and electrical box for wiring than the I-R did, plus it had inter-stage and after-cooling both where the I-R only had one stage of cooling, but the I-R had 100% duty cycle, could run 60 minutes per hour where my P-C was only 50%, 30 minutes in every hour.

If your going to sand blast anything bigger than a small toaster I would not get anything smaller to run a 40# pressure blaster like I have. The ceramic tips wear and they use up a LOT of air real fast. I can easily exceed my duty cycle after 30-40 minutes of blasting.

 

[jchamberlin]

Thanks, Wayne, Dennis, and Dave.

Dennis: I am probably over-thinking, but I tend over-think until I understand. I appreciate the input on the duty cycle. My little die grinder can tax my current and former compressors. I feel like I'm wearing them out when the compressor is constantly running.

Wayne: Thanks for the pictures! I started my search thinking that what you have would be all I would need; yet Dennis is telling us he needs twice the power (7.5 HP) to do everything he wants to do. Either he gets a lot more done than we do or there a few pieces to this puzzle that I'm missing.

In truth, just about anything would be better than what I have right now. I'm trying to avoid an "interim" purchase, where I buy something that I THINK will suit my needs only to find that I need (or can use) more than I thought.

Dave: Thanks for the pointer about the 12 CFM rating --12 CFM seems to be the minimum for most of the standing compressors I've seen advertised, now I know why. I think you're right about the dryer. The NAPA manual shows their Performa line (an I-R style in-line compressor) attached to an air dryer; the less expensive twin cylinder configuration on the Air Boss does not show the air dryer.

From what everyone has related so far, I think I had better plan to purchase as much air compressor as I can (ala Denny's advice) --probably the I-R unit for $999-- and plan to upgrade with a dryer when I get into either the sand blasting or the painting.

Meanwhile I'm going to research the cooling options, just because I'm curious, and I wonder if cooling ability can be added on later as needed.

Again, thanks for helping clear up an old man's befuddlement.

 

[bnolte]

Jeremiah,
It doesn't matter what type of compressor you use, you'll still need an air dryer if you want to use compressed air to do work such as spray painting that requires dry air coming out of the line. Tools like impact wrenches and die grinders last longer when run on dry air as well. Its the physics of compressing and decompressing the air that causes water to accumulate in the tank and air lines, and the more humid the air going in, the more you need an air dryer, whether it is a cheap $199 compressor from Harbor Freight, or a $1500 Ingersoll-Rand.

 

[jchamberlin]

Bruce: Thanks for the tip.

All: After a successful campaign of shaking down the family for the money to buy the Heavy-Duty Ingersoll-Rand 19 CFM compressor with the 80 gallon tank that is designed for a two-person shop (I'm told), I had second thoughts about the purchase. I decided to go with a unit more like Wayne's that is sized more for the hobby-shop/homeowner and which runs less than $700 even when its not on sale, I think it is a 12 CFM unit. It may not have the capacity of the larger machine, but then again, I'm not sure I would ever tap the capacity of the larger machine, and I might have to put up with a lot noise while it takes up more space. As I always say about items on sale, "saving" money on something you don't need is not really a bargain.

I still have to make room for it in the garage, finish running the 220 feed, and figure out exactly how I'm going to run the lines. Now I have to research air driers and figure out where I'm going to put it eventually.

 

[wshytle]

Jeremiah-

What Bruce says is so true and very important. Here is the south we have that thing called humidity too along with the physics Bruce spoke of. I drain my tank often and I'm always amazed at the amount of water. I hope you have a fairly remote area where you can mount the compressor. They are noisy. I installed mine in the basement of the house. It's an old timey basement and not living space; it more like a root cellar.

As far as size goes I've never had problem with capacity while spraying paint, using air tools, or even sandblasting. I do have a 30 gallon "extension" tank I can use in-line but it's not really needed. It's a Craftsman vertical compressor/tank my brother had and the pump went south. I removed the pump and motor (all one unit), installed the pressure gauge, safety valve, valve stem for filling, and the hose back on the bare tank. I did this for portable air but I can also attach it in-line like I mentioned for more volume in case someone has a battleship they need sandblasted. I don't think I'll ever need it as an extension for any reason.

If you find a sixty gallon unit too small you're just not spending enough time in your chair. I think I also mentioned the compressor I have cost less than $500 delivered. I ordered it online from a large tool warehouse. For a 3hp, sixty gallon compressor it has been great. If it ever goes bad I'll replace it with the same.

Good luck with your choice.