Air compressor advice

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Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
3,018
SEPA
Would like some insight into an upcoming purchase. Trying to decide between three electric compressors, specs below:

1. 8 gallon tank 2 HP 125 PSI- Air delivery: 4.5 CFM @ 90 PSI, 5.5 CFM @ 40 PSI
2. 10 gallon tank 2.5 HP 125 PSI- Air delivery: 5.3 CFM @ 90 PSI, 6.2 CFM @ 40 PSI
3. 21 gallon tank 2.5 HP 125 PSI- Air delivery: 4.7 CFM @ 90 PSI, 5.8 CFM @ 40 PSI

#2 is about $30 more than #1, #3 is about $70 more than #1

All three are oil lubed.

I will be using it for DIY on the house, car and tractor, infrequent use, but perhaps heavy use when I need it. I will need to use an extension cord 99% of the time. I have an old house that requires lots of rehab, and its my first go around with this type of large project, so I can't yet say everything that I will need it for.

I'm leaning toward #2, but don't know what I'm missing, like what does the larger tank of #3 get you?


 
Larger tank usually means more tool usage and less compressor running.

What tools are you going to be using with it and how many at one time?


Lopi Rockport
 
Larger tank usually means more tool usage and less compressor running.

What tools are you going to be using with it and how many at one time?


Lopi Rockport
Good questions! My guess is one tool at a time, but don't know which tools. Anything from an impact wrench when rotating the tires to painting. I guess my baseline question is: Is there enough difference between the three to make a real difference for a patient DIY'er?
 
If you're going to be using it inside a lot a larger tank will halo keep the compressor from running constantly while using it during heavy use. Most just complain of the noise levels.

If you're using it with only one tool at a time all should work ok. Except painting depends on how much painting you are going to be doing and how often. If quite a bit then I would opt for the larger tank and then look at recovery times also as you don't want to be using more air than your compressor can provide and possibly loose pressure.

If using multiple tools at the same time you need to figure out what the scfm is of each one and add them together and that is what the compressor should provide at usually 90psi. Most homeowners won't or don't use multiple tools so the scfm of 4 or more usually does the job just fine. It's mainly auto shops roofers and such that use multiple tools constantly unless you will have multiple people working with the same compressor a lot it shouldn't matter.

Personally I would go with the bigger tank but if you need it mobile the smaller ones should work fine. I have a 6 gallon pancake compressor that I use and it won't break free the lugs on my truck (150ft lbs) mainly because of the scfm is almost half of what it needs to work right. And being 6 gallons it runs quite a bit even using an air nailer.

The ones you listed should work for an impact Gun just fine but may run the compressor more with the smaller tank. Same with painting or using tools that run constantly like sanders and what not. If those items are occasionally used they should be just fine.

A bigger compressor is also my next big purchase but I am in the same boat as you as how big do I need it. I won't be using it all the time but when I do I need all my tools to perform the way they need to. I though will only be using one at a time and stationary.




Lopi Rockport
 
If you're going to be using it inside a lot a larger tank will halo keep the compressor from running constantly while using it during heavy use. Most just complain of the noise levels.

If you're using it with only one tool at a time all should work ok. Except painting depends on how much painting you are going to be doing and how often. If quite a bit then I would opt for the larger tank and then look at recovery times also as you don't want to be using more air than your compressor can provide and possibly loose pressure.

If using multiple tools at the same time you need to figure out what the scfm is of each one and add them together and that is what the compressor should provide at usually 90psi. Most homeowners won't or don't use multiple tools so the scfm of 4 or more usually does the job just fine. It's mainly auto shops roofers and such that use multiple tools constantly unless you will have multiple people working with the same compressor a lot it shouldn't matter.

Personally I would go with the bigger tank but if you need it mobile the smaller ones should work fine. I have a 6 gallon pancake compressor that I use and it won't break free the lugs on my truck (150ft lbs) mainly because of the scfm is almost half of what it needs to work right. And being 6 gallons it runs quite a bit even using an air nailer.

The ones you listed should work for an impact Gun just fine but may run the compressor more with the smaller tank. Same with painting or using tools that run constantly like sanders and what not. If those items are occasionally used they should be just fine.

A bigger compressor is also my next big purchase but I am in the same boat as you as how big do I need it. I won't be using it all the time but when I do I need all my tools to perform the way they need to. I though will only be using one at a time and stationary.




Lopi Rockport
Thanks Tegbert, nice reply. I am thinking that portability is one of the most important features for my purposes, this will definitely not be a shop compressor. And, for painting, I may buy a stand alone unit that I won't need the compressor for. May want to use it for sanding.

I think I've narrowed it down to either #1 or #2. And $30 isn't enough to worry about, I suppose.

Good luck with your decision, Tegbert. Let us know what you decide on.
 
If you're going to be using it inside a lot a larger tank will halo keep the compressor from running constantly while using it during heavy use. Most just complain of the noise levels.

If you're using it with only one tool at a time all should work ok. Except painting depends on how much painting you are going to be doing and how often. If quite a bit then I would opt for the larger tank and then look at recovery times also as you don't want to be using more air than your compressor can provide and possibly loose pressure.

If using multiple tools at the same time you need to figure out what the scfm is of each one and add them together and that is what the compressor should provide at usually 90psi. Most homeowners won't or don't use multiple tools so the scfm of 4 or more usually does the job just fine. It's mainly auto shops roofers and such that use multiple tools constantly unless you will have multiple people working with the same compressor a lot it shouldn't matter.

Personally I would go with the bigger tank but if you need it mobile the smaller ones should work fine. I have a 6 gallon pancake compressor that I use and it won't break free the lugs on my truck (150ft lbs) mainly because of the scfm is almost half of what it needs to work right. And being 6 gallons it runs quite a bit even using an air nailer.

The ones you listed should work for an impact Gun just fine but may run the compressor more with the smaller tank. Same with painting or using tools that run constantly like sanders and what not. If those items are occasionally used they should be just fine.

A bigger compressor is also my next big purchase but I am in the same boat as you as how big do I need it. I won't be using it all the time but when I do I need all my tools to perform the way they need to. I though will only be using one at a time and stationary.




Lopi Rockport

Any normal pancake compressor will have plenty of air compressed to get your lug nuts off. The failure was your weak impact gun. It only takes a small squirt of air to run such a tool to its max ability.

For the op I highly recommend the 100$ pancake style compressor. Plenty of air for nailing, which is the main remodel air tool, easy on power needs, and most importantly is easy to move. easily carry in one hand to the project site.

I'm a fan of the two compressor plan. One for sandblasting, painting, big stuff which would be a 60-80 gallon unit. The other for everything else. I have found the pancake to be so very capable (even removing 150 ft-lb F350 lug nuts) that I never bought the big one.
 
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Any normal pancake compressor will have plenty of air compressed to get your lug nuts off. The failure was your weak impact gun. It only takes a small squirt of air to run such a tool to its max ability.

For the op I highly recommend the 100$ pancake style compressor. Plenty of air for nailing, which is the main remodel air tool, easy on power needs, and most importantly is easy to move. easily carry in one hand to the project site.

I'm a fan of the two compressor plan. One for sandblasting, painting, big stuff which would be a 60-80 gallon unit. The other for everything else. I have found the pancake to be so very capable (even removing 150 ft-lb F350 lug nuts) that I never bought the big one.

I wish it was a weak impact. It is a matco impact while about 10 years old on the right air source has no issues at all


Lopi Rockport
 
None of them will run an air sander. My big 7 horse 110 gal shop compressor is working to keep up if I run a sander and anything else they use tons of air for a long time. I tried running a sander off of my 30 gal 150psi portercable one and it just couldn't keep up at all. The sander was always running slow and leaving nasty swirl marks. Just buy a good electric sander unless you are going to be doing allot of production sanding and are going to invest in a big shop compressor. Also a good electric sander is cheaper than a good air sander. But I really do prefer air
 
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I have #2. Just pick one up, you'll be fine. Harbor Freight hasn't screwed air compressors up yet. Its light enough to easily move around. 3 isn't heavy, but starting to get bulky.
 
Any normal pancake compressor will have plenty of air compressed to get your lug nuts off. The failure was your weak impact gun. It only takes a small squirt of air to run such a tool to its max ability.

For the op I highly recommend the 100$ pancake style compressor. Plenty of air for nailing, which is the main remodel air tool, easy on power needs, and most importantly is easy to move. easily carry in one hand to the project site.

I'm a fan of the two compressor plan. One for sandblasting, painting, big stuff which would be a 60-80 gallon unit. The other for everything else. I have found the pancake to be so very capable (even removing 150 ft-lb F350 lug nuts) that I never bought the big one.
Thanks Highbeam. Any reason why pancake would be better than the hotdog shaped tank?
 
None of them will run an air sander. My big 7 horse 110 gal shop compressor is working to keep up if I run a sander and anything else they use tons of air for a long time. I tried running a sander off of my 30 gal 150psi portercable one and it just couldn't keep up at all. The sander was always running slow and leaving nasty swirl marks. Just buy a good electric sander unless you are going to be doing allot of production sanding and are going to invest in a big shop compressor. Also a good electric sander is cheaper than a good air sander. But I really do prefer air
Thanks bholler, good to know about the sander, I picked up an orbital one last year that seems to work fine, so I just need a belt sander for heavy work, and electric will do.
 
Thanks Highbeam. Any reason why pancake would be better than the hotdog shaped tank?

No reason to prefer one shape over the other but keep an eye on cost, simplicity, stability on a roof, lightweight, and portability. I usually don't even bother with a really long air hose, just move the compressor with me and plug in to the closest outlet. It's a one hand deal.
 
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Funny thing about air compressors - when i got my first one, it was a smallish air compressor and it ran a few things i thought would be nifty. brad nailer, impact, blow gun to clean out my computers. Then i kept finding more and more jobs for it. Getting frustrated of running low on air, I upgraded the compressor. same thing happened. finally broke down and got a large unit and ran piped air to the basement, house and garage. really comes in handy. So i say go for the large tank, which gives you longer tool run time. I know you narrowed it down to 3 units but i would also look for a higher psi than 125. reason is say it was 180 psi. that means the compressor shuts off when the tank is 180 psi. that stores more air in the tank than 125. if you were running a tool at 40 psi, you can use that tool longer than you could have with 125 psi air stored in the tank.

so take a long hard look at the tools you want to run now and in the future before you buy.

Some downsides to a large tank compressor: it will take longer to fill up. It is heavier and not easy to move.

i think the best setup is a high CFM compressor with a high psi, and a small tank that is quick connected to a large tank. then you get the option of portable or high yield when you want it.
 
Funny thing about air compressors - when i got my first one, it was a smallish air compressor and it ran a few things i thought would be nifty. brad nailer, impact, blow gun to clean out my computers. Then i kept finding more and more jobs for it. Getting frustrated of running low on air, I upgraded the compressor. same thing happened. finally broke down and got a large unit and ran piped air to the basement, house and garage. really comes in handy. So i say go for the large tank, which gives you longer tool run time. I know you narrowed it down to 3 units but i would also look for a higher psi than 125. reason is say it was 180 psi. that means the compressor shuts off when the tank is 180 psi. that stores more air in the tank than 125. if you were running a tool at 40 psi, you can use that tool longer than you could have with 125 psi air stored in the tank.

so take a long hard look at the tools you want to run now and in the future before you buy.

Some downsides to a large tank compressor: it will take longer to fill up. It is heavier and not easy to move.

i think the best setup is a high CFM compressor with a high psi, and a small tank that is quick connected to a large tank. then you get the option of portable or high yield when you want it.
Thanks Dr. I can see what you are saying. I have an uncle who has a large, high psi unit in his shop, and he uses it a lot. That said, he's a large scale farmer with lots of equipment to manage.

Unfortunately, my imagination is not what it used to be, so I was hoping you might provide 3 or 4 examples of jobs that you do that run you out of air.
 
painting is a biggie. i was disappointed to run out of air with a die grinder, air drill, air ratchet, and a small air hammer i was using to remove my tile floor in the bathroom.

When i had my roof redone, i was happy to have enough air to support 4 men running 4 nailers continuously for hours. Most of all I use the blow gun for cleaning out my pellet stove. The compressed air combined with the leaf blower trick gets it amazingly clean but uses a suprising amount of air.

I even have a pneumatic log splitter which works but is a pita to use, in hindsight i would have bought or rented a gas one.

basically most compressors will run any tool for short bursts. If you want to run it continuous then you need the larger tank.

I hope this helps. just keep in mind that the bigger the unit the less portable it is. I also use the blow gun for household cleaning now. air conditioner filters, the dust on fans. my wife uses it for her nick nacks sp?
 
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I'm in the having 2 compressors camp. In the shop I've got an old speed-aire cast iron dual piston belt driven one. Nice and quiet and pumps up quick. Then I have a small pancake 2 gallon for lugging around. There's a reason behind the madness though. Compressors need a lot of amps to start. If your running anything else when it starts, like a miter saw, it may trip your breakers. Add in a 50ft extension and the draw is even more. A small pancake compressor can be had for darn near the cost of a good 12awg extension cord. Plus I'm not tripping over extra cords while I'm working. 2 gallons is not enough for production work but for 90% of the handy man stuff it works great. If I got to use the big one I have enough hose that I don't need a extension most of the time.
 
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I'm in the having 2 compressors camp. In the shop I've got an old speed-aire cast iron dual piston belt driven one. Nice and quiet and pumps up quick. Then I have a small pancake 2 gallon for lugging around. There's a reason behind the madness though. Compressors need a lot of amps to start. If your running anything else when it starts, like a miter saw, it may trip your breakers. Add in a 50ft extension and the draw is even more. A small pancake compressor can be had for darn near the cost of a good 12awg extension cord. Plus I'm not tripping over extra cords while I'm working. 2 gallons is not enough for production work but for 90% of the handy man stuff it works great. If I got to use the big one I have enough hose that I don't need a extension most of the time.
Thanks rwhite. This begs the question, is there enough gain between the 10 gallon tank and the ultra-portable 2 gallon one you describe to make the 10 gallon one worth it?
 
My pancake is 6 gallon, 150 psi, 100$ from home depot, one hand carry, and low power draw. Just used it today for the die grinder and brad nailer in the kitchen. I would not want anything with a bigger tank for my "small" compressor.
 
Thanks rwhite. This begs the question, is there enough gain between the 10 gallon tank and the ultra-portable 2 gallon one you describe to make the 10 gallon one worth it?
IDK, my big one is only 12 gallon. But it's a dual piston and recovers quick . Enen tough it has wheels its not really portable for dragging up steps and through the house. I prefer it over my previous 20 gal Husky. The Husky was loud.
 
My pancake is 6 gallon, 150 psi, 100$ from home depot, one hand carry, and low power draw. Just used it today for the die grinder and brad nailer in the kitchen. I would not want anything with a bigger tank for my "small" compressor.
I'll check it out. Sounds like about what I'm looking to do. Thanks Highbeam.
 
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I have been loving my ingersoll rand UP6-7.5-125

Sent from my SAMSUNG-SM-G890A using Tapatalk
 
I'll check it out. Sounds like about what I'm looking to do. Thanks Highbeam.
A 6 gal will darn near do every Thing but paint. I had a twin tank cheap alltrade at one point that I abused the heck out of. Finally gave up the ghost after 15 years of hard labor. I think I paid $75 at AutoZone for it.
 
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I bought a 20 gallon airless compressor quite a few years ago. Not as deluxe, I guess. It came with wheels. I put in a Harbor Freight hose reel retractor near it that's proven useful for keeping the hose unkinked.

I originally got it to blow out the sprinkler system I put in, to save money from hiring someone and I figured I 'needed' one. It really doesn't have the capacity that's needed, and it was quite tedious, but it worked.

Now, in the 'new' house (been here 11 years), I have a long garden hose going something like 400' out to the 'road garden', and I use it to blow out that hose, which works fine. I've blown out some pipe inside the house to get some pesky water out.

It mostly stays in one spot in the garage. Like I said, the retractable hose real is nice. I bought some extra hose to work inside the house, but the door has to be cracked open, but the noise is out in the garage.

It came with a wrench and sprayer. I never tried the sprayer. I tried the wrench and it couldn't remove the lug nuts on a car. I don't think I was doing anything wrong, but someone told me, like the person above, that the quality of the wrench makes a lot of difference.

I haven't been as diligent as I used to be about draining the water. I'll try harder. They rust out, I hear.
 
I've had numerous compressors of varying sizes and types.
If I had to do it all over again I'd buy a small portable electric compressor and use electric tools where ever possible.
Air tools are very inefficient, noisy, etc. Even electric versions of impact wrenches and paint sprayers work well.