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bdahlg68
11-16-2012, 08:10 PM
10 gal, 5.30 CFM at 90 PSI, Maximun pressure - 125 PSI

or

15 gal, 5.0 CFM at 90 PSI, Maximum pressure - 200 PSI

or both just too small?

Not painting cars and not a pro... but my current 2.6CFM at 90 PSI out of 5.5 gal just doesn't cut it. Seems if I double that, that is a big step. Looking to stay pretty quiet and both above units are below 80 dBA.

Does the extra pressure / gallons really help much?

Sieg
11-16-2012, 08:44 PM
I'd consider this as a starting point: http://www.aircompressorsdirect.com/Eagle-C4160V1-Air-Compressor/p5515.html

If you're planning on running any air grinders/sanders you need a larger tank. My Ingersoll-Rand 3.3hp 20 gal unit gets it butt kicked by a 2" Harbor Freight sander. I've yet to own a compressor for my garage that's had enough CFM or achieved the stated PSI rating. This or the 18.5 CFM unit is my plan.

Regarding dBA levels, the larger the tank the less they'll be running. :thumbsup:

bdahlg68
11-16-2012, 08:51 PM
was looking there as well. for a few hundred more, i could step up to 60 gal and 7.1 CFM @ 90PSI....

http://www.aircompressorsdirect.com/BelAire-2061V-Air-Compressor/p4786.html

Was hoping to use that few hundred elsewhere, but could go this way too.

Sieg
11-16-2012, 08:58 PM
was looking there as well. for a few hundred more, i could step up to 60 gal and 7.1 CFM @ 90PSI....

http://www.aircompressorsdirect.com/BelAire-2061V-Air-Compressor/p4786.html

Was hoping to use that few hundred elsewhere, but could go this way too.
Have you ever had a car with too much horsepower?

I've been researching this subject too long..........as a hobbiest spend $500 and still be disappointed, spend $800 and be OK, or spend $1000-$1500 and smile everytime you use it for the rest of your life. Sucks doesn't it. ;)

GregWeld
11-16-2012, 09:38 PM
Okay -- here's the only way to MATE your compressor with your job requirements...


Go find your air tools you plan to use..... they will be "rated" with a minimum CFM (cubic foot per minute) at a specified PSI....


So if your die grinder needs 3 cfm at 90 psi..... then to buy a compressor with anything less than capable than that -- you'll be waiting for the SOB to make pressure --- and the thing will be running continuously.


My commercial Champion 5 hp with an 80 gal vertical tank will produce about 19 cfm at 125psi --- and will keep up with my hand tools... but anything much less would be a complete PITA.

bdahlg68
11-17-2012, 08:26 AM
Okay -- here's the only way to MATE your compressor with your job requirements...


Go find your air tools you plan to use..... they will be "rated" with a minimum CFM (cubic foot per minute) at a specified PSI....


So if your die grinder needs 3 cfm at 90 psi..... then to buy a compressor with anything less than capable than that -- you'll be waiting for the SOB to make pressure --- and the thing will be running continuously.


My commercial Champion 5 hp with an 80 gal vertical tank will produce about 19 cfm at 125psi --- and will keep up with my hand tools... but anything much less would be a complete PITA.

Yeah, I've looked at that. Highest consumption right now is 5-5.5 CFM @ 90 PSI. Thinking the 7.1 @ 90 is enough especially with 60 gal.

Fluid Power
11-17-2012, 12:12 PM
Guys, I own a Fluid Power distribution company and deal with air systems for a living. Like Sieg said, speed $1500 and buy an industrial grade compressor and then forget about it for the rest of your life. Atlas Copco makes really nice compressors (we do not sell them) with 5hp Baldor industrial grade motors. These motors are about twice the size of the motors seen on the big box stores compressors (and the link) and are true rated motors. The Copco that we test all our equipment on is super quite and will push 19cfm at 125 psi as well. It is a 5hp model. We paid $1600 for it. Look around at some auto body supply shops, fluid power distributors etc. or an industrial compressor dealer. Ask them questions.

Darren

Sieg
11-17-2012, 01:30 PM
My commercial Champion 5 hp with an 80 gal vertical tank will produce about 19 cfm at 125psi --- and will keep up with my hand tools... but anything much less would be a complete PITA.

Yeah, I've looked at that. Highest consumption right now is 5-5.5 CFM @ 90 PSI. Thinking the 7.1 @ 90 is enough especially with 60 gal.

I think you missed Greg's key point........subconcious attempt to favor your budget? :D :thumbsup:

GregWeld
11-27-2012, 07:42 PM
I'm a firm believer in buying good tools -- particularly the type that you'll buy ONCE and use forever... I consider these "investments". A good compressor is worth every dime you spend on it every time you use it -- and will be worth as much as you paid for it - 15 years from now.

It's like buying a Snap-On wrench -- you only buy it ONE TIME and use it 'til you die. I'm thinkin' that's a pretty good buy. :D

bdahlg68
11-27-2012, 11:29 PM
Greg - agreed. I don't want to buy twice. But, I also don't want to buy more than what I need. I'm willing to buy a good product and pay for it. I'm not willing to buy a $5,000 compressor that spits out huge CFM as that doesn't appear to be what I need. I haven't seen a tool that I would use that requires over about 6 CFM at 90 PSI. Most of those also won't run 100% of the time so as to not run into duty cycle problems.

Any experience with Quincy compressors? Seems I can step up CFM without stepping up noise or cost. 12.4 CFM and 50% duty cycle seems like it would cover my needs.....

http://www.northerntool.com/shop/tools/product_200479713_200479713

GregWeld
11-28-2012, 02:51 PM
The Quincy compressor specs are FAR better than the original version you asked about -- and Quincy is a good brand name.

It's still "not enough" compressor -- but will work... and the price is certainly cheap. I will stick by my guns though and say -- for large items like this -- it pays (in the long run) to buy a REAL version you can grow with. But I also understand people have budgets to live with too.

I bought a lift from EAGLE -- that I thought "was good enough".... and was about 1/3rd less than the Rotary Lift I really wanted. 6 years later I gave the Eagle lift away for less than half what it cost... and bought the Rotary. Saved a bunch of dough on that deal.... :lol:

Fluid Power
11-28-2012, 06:55 PM
The Quincy compressor specs are FAR better than the original version you asked about -- and Quincy is a good brand name.

It's still "not enough" compressor -- but will work... and the price is certainly cheap. I will stick by my guns though and say -- for large items like this -- it pays (in the long run) to buy a REAL version you can grow with. But I also understand people have budgets to live with too.

I bought a lift from EAGLE -- that I thought "was good enough".... and was about 1/3rd less than the Rotary Lift I really wanted. 6 years later I gave the Eagle lift away for less than half what it cost... and bought the Rotary. Saved a bunch of dough on that deal.... :lol:

EXACTLY. Nothing short of an industrial compressor is satisfactory. Nothing from the big box DIY stores or northern tool etc. Call somebody that deals in compressors.

Here is who we use:

http://www.aircompressors.com/products/air-compressors/atlas-copco/kt/

Buy a KT5V80. Shouldn't be more than $1500.00. Whisper quite. Last the rest of your life. I went thru 2 Craftsman compressors before this.

Buy it once.

Darren

GregWeld
11-28-2012, 07:14 PM
Okay -- this is going to be a bit risky to post... and I'm sure it will also be controversial... but here goes nothing.


A buddy of mine does everything on a budget... he has a two car garage and didn't want to take up a bunch of foot print for a compressor.

He used several 10 foot lengths of schedule 80 thick wall 6" PVC pipe plumbed together in a series as his "tank" -- he stuck these up in the attic crawl space.... and his "compressor" was a real good commercial motor and pump that produced plenty of air. His regulator controlled the "tank" psi to 125.

Schedule 80 pipe is good enough to hold 125 lbs (our working pressures)... but Google the ratings because this varies depending on the diameter of the piping and it's rating goes DOWN with diameter!

My guess is -- he spent as much on all the pipe and fittings and pump etc as he could have just gone out and bought a good compressor! :willy: :faint:

bdahlg68
11-28-2012, 08:12 PM
Okay -- this is going to be a bit risky to post... and I'm sure it will also be controversial... but here goes nothing.


A buddy of mine does everything on a budget... he has a two car garage and didn't want to take up a bunch of foot print for a compressor.

He used several 10 foot lengths of schedule 80 thick wall 6" PVC pipe plumbed together in a series as his "tank" -- he stuck these up in the attic crawl space.... and his "compressor" was a real good commercial motor and pump that produced plenty of air. His regulator controlled the "tank" psi to 125.

Schedule 80 pipe is good enough to hold 125 lbs (our working pressures)... but Google the ratings because this varies depending on the diameter of the piping and it's rating goes DOWN with diameter!

My guess is -- he spent as much on all the pipe and fittings and pump etc as he could have just gone out and bought a good compressor! :willy: :faint:

I thought about piecing a system together but figured sort of the same... at the end it'd cost just about as much but take a lot more of my precious time. Maybe I'll win Powerball tonight and this is all moot. Alternatively I can do nothing and maybe outsource more work rather than spend the money on equipment.

Greetings from smoggy Shanghai.... the land of not quite right.

clill
11-29-2012, 03:14 PM
Food for thought. My big deal for a compressor has always been for impact wrenches,air drills etc.Now i find I use a cordless impact, drill etc all the time. I don't do body work so I don't need a compressor for that. In my clean barn I have a 5 hp compressor and in the wall I ran about 150' of 2" schedule 80 PVC . PVC is pretty cheap but if it bursts it makes shrapnel that can't be spotted with X-ray. It's either old age or the advent of all the cool rechargeable cordless tools but I find my biggest use these days for the air compressor is to air up tires and to blow out the shop.

GregWeld
11-29-2012, 05:26 PM
Good post Charley!


I just got my new DeWalt 1/2" drive impact wrench today from Amazon... it came with two batteries and a charger and they tossed in a 3rd battery on the special deal. (stole your idea from when we were at the track and needed an impact wrench!)


However..... Unlike Charley - I use the hell out of my compressor and far prefer air tools over electrics. I use air drills -- air saws -- grinders... blower tools for cleaning stuff etc -- not to mention my blast cabinet - which seems to be used non stop by everyone but me.... So to me -- the compressor is really an important part of the "shed". Since it doesn't leak -- it's left on and ready to use unless I'm going out of town for a week or so....

rustbucket69
11-29-2012, 05:48 PM
I bought the "cheapest" Quincy Compressor from Northern Tool and absolutely LOVE it. As previously stated about another brand, Quincy used Baldor motors, and it is HUGE. Also, being made in the USA was a nice selling point for me. I have a small table top blast cabinet and all the standard air tools, and this thing doesn't skip a beat. Quick fill time and long time between regeneration with basic air tool usage. I looked at IR and some of the others, but was turned off by the use of Emerson motors made in Mexico, cheap switching mechanisms (Quincy uses Square D), and the overall lack of build quality.

I agree with the others' statements that the compressor was an investment tool. I had to really convince myself that $1200 for a compressor was better than a $600 compressor and $600 in parts or something else, but after buying and using it, I have no regrets. Another nice thing about the Quincy is that it is relatively quiet (compared to other units I've heard) which is nice since I only have a 2 car garage with small bump out for my "shop" and cannot remotely locate it.

Stick to your guns and budget, but if you choose to "invest," I'd highly recommend Quincy.

clill
11-29-2012, 06:18 PM
I forgot about my blast cabinet. I have a 10 hp rotary in that shop and my cabinet is a full pressure type. The compressor keeps up fine but more for a commercial type Shop. I still think that these days you can do most stuff with cordless stuff and not have to deal with cords and hoses.

bdahlg68
11-29-2012, 09:00 PM
I also have lots of cordless or electric tools. Prefer air for certain applications also and also just want the flexibility. We'll see. Don't want to be unhappy / unsatisfied, but at a certain point the money is better spend elsewhere right now.Thanks for tips and pointers everyone.

GregWeld
11-29-2012, 09:13 PM
In my clean barn I have a 5 hp compressor and in the wall I ran about 150' of 2" schedule 80 PVC . PVC is pretty cheap but if it bursts it makes shrapnel that can't be spotted with X-ray


The good news is the BURST rating of 1" schedule 80 PVC is 2000 PSI.... yep you read it right -- TWO THOUSAND PSI.... and it's rated for a maximum working pressure of 500 PSI... so your 125 or 150 psi should keep you out of the XRay room!

:lol:

It really is good cheap "air storage" AND it doesn't rust!!

Sieg
11-29-2012, 11:18 PM
I also have lots of cordless or electric tools. Prefer air for certain applications also and also just want the flexibility. We'll see. Don't want to be unhappy / unsatisfied, but at a certain point the money is better spend elsewhere right now.Thanks for tips and pointers everyone.

I was thinking about you while listening to my air compressor running constantly with my 2" sander earlier this week. Ingersoll-Rand 20 gal, 3.3 hp, rated 10 cfm @ 40 psi, 7.4 @ 90, 100 psi max pressure. The little air sander kicks it's butt in less than a minute of continuous run time. :willy:

GregWeld
11-30-2012, 09:42 AM
Here's the part people don't understand about compressors... The tank just holds air at a set psi (Max and min) -- once the minimum setting is reached -- the motor and pump kick on... if they ARE NOT capable of producing more air than is required by the tool -- they'll never catch up.

That's why just matching the numbers of the tool with a compressor that is rated @ LESS or almost the same doesn't work. It doesn't matter how big the storage tank is -- that just gives you a "use time" BEFORE the compressor has to kick on -- but then once it does - it's going to run full blast and never catch up.

People don't realize how seriously annoying that is. Not having enough air to just do the work - AND listening to the stupid compressor run and run and run.

clill
11-30-2012, 09:47 AM
"The good news is the BURST rating of 1" schedule 80 PVC is 2000 PSI.... yep you read it right -- TWO THOUSAND PSI.... and it's rated for a maximum working pressure of 500 PSI... so your 125 or 150 psi should keep you out of the XRay room! "

The problem isn't with the sticks of pipe, it is usually the fittings that break.

GregWeld
11-30-2012, 09:58 AM
The problem isn't with the sticks of pipe, it is usually the fittings that break.



Well.... you can't use schedule 40 fittings on schedule 80 pipe if you want the same ratings! :rofl: :rofl: :rofl: :rofl:

Fittings and pipe carry the same rating... but the big box stores will carry only schedule 40 stuff. I'm going to have to come down there and take you to a real plumbing store!!

Of course -- I'm not saying YOU did this... as usual... I write my posts so that OTHER people reading them will get info to think about. :cheers:


What I find with most people is that they over tighten PVC fittings... or don't use primer before gluing. Using teflon tape on the threaded fittings makes it real easy to over torque them. We're all used to torquing engine fittings! :lol:

Sieg
11-30-2012, 10:25 AM
People don't realize how seriously annoying that is. Not having enough air to just do the work - AND listening to the stupid compressor run and run and run.
I have...........for years now. :willy:

Also the more it runs the more condensation it makes.........right?

Nothing like having a water injected sander............another system you don't want to skimp on is your in-line filter/dryer. :thumbsup:

GregWeld
11-30-2012, 10:46 AM
Well said Sieg!


The less the compressor runs -- the less water.

Best plumbing website I've found FOR IDEAS HOW TO RUN LINES ETC --- is TP TOOLS.


DO NOT BUY THEIR PLUMBING -- they use IRON PIPE -- what happens when you mix water and iron?

Personally -- all my plumbing is COPPER... all my "take off lines" run UP from the main supply lines -- and there's a drain at the bottom of every take off... and an oil/water separator on the main. You'd be amazed at how much water blows out when I open the drain valve.

You'll see how this all works on the TP Tools website. The key is to not push water directly to your tool... YOU WILL have water in the lines. Now it's just a matter of dealing with it.

So in the Pacific NorthWET -- we have high humidity.... and if you think about compressing AIR -- you're also compressing that humidity at the same rate. We're not separating the INTAKE air from the moisture held in it! Thus - we do that on the output side. I'd say it sucks -- but really -- it blows! HAHAHAHAHA

Fluid Power
11-30-2012, 12:18 PM
The problem with PVC is not the pressure rating, the drama stems from 4 factors:

1) It is does not expand and contract evenly, creating weak spots. This is where the risk of explosion comes in.

2) It is not UV resistant. It breaks down over time.

3) Compressor oils react with the PVC creating weak spots.

4) It is brittle. A small impact could cause an explosion.

Pressure ratings don't mean squat when you have a compressor that is blowing oil thru the PVC lines or something hits the PVC pipe and it bursts.

While it is a pain in the neck to use black iron pipe, good compressor habits eliminate the issues and should be followed using BIP, Copper or aluminum.

1) Clean dry air is the basis for any compressed air systems. Running proper filters and regulators is a must on ANY type of CA system, whether plumbed with copper, aluminum or BIP.

2) BIP will scale, and point of use filters should be used if running a sensitive piece of equipment or automation type machines. Your impact wrench or sander will not care if there is a little scale in the lines. (you do oil them before use, correct?) A point of use filter should be used if painting (regardless of how the system is plumbed)

3) Proper compressor maintenance and a properly plumbed air system goes a long way in reducing water/scale in an air system. Draining the compressor after use and having a proper Filter Regulator will make whole system work better.

Darren

Sieg
11-30-2012, 12:45 PM
Good or bad my garage is plumbed with copper tubing.

Fluid Power
11-30-2012, 01:34 PM
Good or bad my garage is plumbed with copper tubing.

No drama. :thumbsup:

GregWeld
11-30-2012, 01:35 PM
Good or bad my garage is plumbed with copper tubing.





COPPER IS PROPER


:rofl: :rofl: :rofl:

DRJDVM's '69
11-30-2012, 03:56 PM
Don't buy a compressor for the requirements you need right now.....get the best compressor you can afford for what you will need in 3-5 years.... It's a virtual guarantee that you will add stuff in the future that will add to your compressor requirements....

Same goes for a welder.....

And building a shop.....

And picking a wife.... :)

GregWeld
11-30-2012, 04:50 PM
And picking a wife.... :)



Yes --- ALWAYS check out the future MOTHER IN LAW to see what you're wife will look like in the future... If you think you can live with the "rust and the chips in the paint" - then go for it!

:rofl: :rofl: :thumbsup:


Compressors can be upgraded relatively inexpensively!

fleetus macmullitz
12-07-2012, 03:34 PM
Yes --- ALWAYS check out the future MOTHER IN LAW to see what you're wife will look like in the future... If you think you can live with the "rust and the chips in the paint" - then go for it!

:rofl: :rofl: :thumbsup:



Classic...

And if things ain't good between the future wife and 'daddy'...watch out. :rolleyes: