I will be getting a small portable 1 gallon 135 PSI Porter Cable compressor. It will fit all my needs, I think. One day, I will have a larger project, a framing nail gun for example, that requires a larger capacity compressor. Can I attach a 2 galon air tank to the output of the compressor and in effect, end up with an equivalent 3 gallon compressor? I don't know a whole lot about compressors.
Compressor + Air Tank
- Thread starter xroad
- Start date
Only sort of.
An air compressor has two main components: the pump which fills the tank.
For 'sustained' use, you need a pump which can pump enough air to run the tool(s).
For 'intermittent' use, you can sort of rely on the compressed air that is stored in the tank.
Think of the air tank as a rechargeable battery. The bigger the battery, the more you can use it before you have to recharge. But you will have to recharge it sooner or later, and then the time it takes for the battery to get 'refilled' depends on the charger. (leaving out some of the 'finer' details, etc, etc, etc).
So although you can (within limits, see the rest of this paragraph) add more air tank storage/capacity, that means that the pump will have to run longer to refill all that capacity. And most compressor pumps are made/designed to only run a certain percentage of the time (duty cycle), and then they need to stop and cool off. Most units have the pump size and duty-cycle roughly matched to the tank size and general 'usage profile'.
So although a little compressor pump that might come with a little 1 gallon tank could (theoretically) fill a big 80 gallon air tank, the little compressor pump will definitely suffer from a reduced (greatly reduced) lifetime and will likely self-destruct pretty soon if it ran long enough to try and fill the big 80 gallon air tank.
For air compressors, you generally want to size it based on the CFM the compressor can deliver and the CFM of the tool(s) you want to run. And then get 2x the compressor CFM as the tools need (ex: tool needs 5 CFM, so try and get a compressor that can supply 10 CFM). Note that some tools are 'rated' on an intermittent basis for the CFM demand, and the sustained CFM can easily be 4x as high or higher (ex: an air die grinder may be 'rated' at 5 cfm air usage, but that is based on an intermittent air usage of just 15 seconds use in 1 minute elapsed time, so if you will be using that grinder on a sustained/continuous basis you would need an air compressor that could supply 20+ cfm).
A little 1 gallon air compressor can run most air nailers OK, but you may end up waiting for the tank to refill before you can fire the next 'shot' if you have a bigger nailer (like a framing nailer). YMMV.
In general, get the biggest air compressor you can afford and fit.
Almost no one ever says "Gee, I wish I had gotten the smaller air compressor."
(larger industrial screw air compressors exempted there)
An air compressor has two main components: the pump which fills the tank.
For 'sustained' use, you need a pump which can pump enough air to run the tool(s).
For 'intermittent' use, you can sort of rely on the compressed air that is stored in the tank.
Think of the air tank as a rechargeable battery. The bigger the battery, the more you can use it before you have to recharge. But you will have to recharge it sooner or later, and then the time it takes for the battery to get 'refilled' depends on the charger. (leaving out some of the 'finer' details, etc, etc, etc).
So although you can (within limits, see the rest of this paragraph) add more air tank storage/capacity, that means that the pump will have to run longer to refill all that capacity. And most compressor pumps are made/designed to only run a certain percentage of the time (duty cycle), and then they need to stop and cool off. Most units have the pump size and duty-cycle roughly matched to the tank size and general 'usage profile'.
So although a little compressor pump that might come with a little 1 gallon tank could (theoretically) fill a big 80 gallon air tank, the little compressor pump will definitely suffer from a reduced (greatly reduced) lifetime and will likely self-destruct pretty soon if it ran long enough to try and fill the big 80 gallon air tank.
For air compressors, you generally want to size it based on the CFM the compressor can deliver and the CFM of the tool(s) you want to run. And then get 2x the compressor CFM as the tools need (ex: tool needs 5 CFM, so try and get a compressor that can supply 10 CFM). Note that some tools are 'rated' on an intermittent basis for the CFM demand, and the sustained CFM can easily be 4x as high or higher (ex: an air die grinder may be 'rated' at 5 cfm air usage, but that is based on an intermittent air usage of just 15 seconds use in 1 minute elapsed time, so if you will be using that grinder on a sustained/continuous basis you would need an air compressor that could supply 20+ cfm).
A little 1 gallon air compressor can run most air nailers OK, but you may end up waiting for the tank to refill before you can fire the next 'shot' if you have a bigger nailer (like a framing nailer). YMMV.
In general, get the biggest air compressor you can afford and fit.
Almost no one ever says "Gee, I wish I had gotten the smaller air compressor."
(larger industrial screw air compressors exempted there)racingtadpole
Well-known member
Mate, thats really well written. Good explanation.
vartz04
Well-known member
Adding an air tank just allows you longer time between compressor on cycles but also increases the length of the compressor on cycle. You really gain nothing because the longer run time means a longer wait time for recharge. The only case where this makes sense is say you use a cut off wheel every now and then, and it takes you X amount of seconds to cut through the material you are cutting but the compressor only will run the wheel long enough to get you 3/4 of the way through. Then the tank will allow you to cut completely through the item before a recharge cycle.
Honestly id go for a 6 gallon pancake compressor if all you are going to do is use it for nailing. Check craigslist they are on there cheap all the time.
Realistically for home use id be looking at a 20-30 gallon vertical compressor on wheels that can be rolled to the project. Something that runs on 120v circuits so you can plug it in anywhere. That way you can run any nail gun out there, an impact gun, and some other air tools for a short time.
Edit: you typed faster than me but we basically said the same thing.
Honestly id go for a 6 gallon pancake compressor if all you are going to do is use it for nailing. Check craigslist they are on there cheap all the time.
Realistically for home use id be looking at a 20-30 gallon vertical compressor on wheels that can be rolled to the project. Something that runs on 120v circuits so you can plug it in anywhere. That way you can run any nail gun out there, an impact gun, and some other air tools for a short time.
Edit: you typed faster than me but we basically said the same thing.
Most of the time, the pressure shut-off (and start-up) switch on the compressor is set at the factory. You don't need to adjust anything there.
You do usually need to set the pressure regulator output (from the tank/compressor into the air line/hose) so you have the 'proper' air pressure for the tool(s) in use at that time. Sometimes you need/want 30 psi, sometimes you need/want 60 psi, sometimes you need/want 90 psi.
You do usually need to set the pressure regulator output (from the tank/compressor into the air line/hose) so you have the 'proper' air pressure for the tool(s) in use at that time. Sometimes you need/want 30 psi, sometimes you need/want 60 psi, sometimes you need/want 90 psi.
vartz04
Well-known member
Tank should fill to max pressure of the tank (should be close to that or at that from the factory). regulator should be 5-10PSI above what the tool needs (to account for pressure losses through the fittings/hose)
If you are filling up an aux tank though set the regulator to the max pressure of the aux tank. Then you need another regulator to drop it down after the aux tank to the tool pressure.
If you can I would honestly just go buy a bigger compressor. you can snag a 20-30 gallon unit for around $150 all day long on craigslist.
If you are filling up an aux tank though set the regulator to the max pressure of the aux tank. Then you need another regulator to drop it down after the aux tank to the tool pressure.
If you can I would honestly just go buy a bigger compressor. you can snag a 20-30 gallon unit for around $150 all day long on craigslist.
As I said earlier, I know very little of air tools and equipments. Does this mean the length of hose makes a difference on the regulator setting? For example, 25 feet of hose vs. 100 feet of hose ... I should have the setting a bit higher for the longer hose?
That leads to another question. As the compressor cycles, does (should) my 18 gauge nailer performance varies between the cut in and cut out pressure? I see my output gauge showing a range of 95 psi to 125 psi.
Air hose length does affect the flow rate through the air hose (and any fittings).
Most of the time, you don't have to worry about it. But don't go and hook up 200 ft of 1/4 inch air hose with 1/4 inch fittings and then try to run an air-hungry tool. Cause all that skinny air hose and all the small diameter fittings will 'starve' the tool from the air (pressure and flow) that it needs to operate correctly.
The pressure:flow-rate values most often need to be adjusted or compensated for high(er) pressure and high(er) flow rates. Tools like an air die grinder (high pressure and high flow rate), an air impact gun (high pressure and high flow rate), maybe a high pressure spray gun (high flow rate and medium pressure, but values need to adjusted carefully as they greatly affect the spray characteristics), and other such tools.
For 'critical' air tools (such as a precision spray gun), you might go to putting a pressure regulator or at least a pressure gauge right at the tool to monitor or set the air pressure at the tool. And you would set the air pressure while actually spraying (which then automatically compensates for flow rate losses through all the hose and fittings up to that point).
Air nailers are usually not quite so sensitive to flow rates, as they dump a relatively small amount of air per 'shot' (big framing nailers excluded).
As I said above, generally get the biggest air compressor you can afford. More air is 'better', in that you can use more air tools. Well, not so much 'better' for the wallet though.
re: air pressure. As long as the tank pressure is higher than the regulated output pressure, the regulated output pressure (which is what pressure is being sent to the tool) isn't really varying. When the tank pressure drops lower than the desired/regulated output pressure, then you are sending a reduced air pressure to the tool(s) and they may or may not work 'right'.
For 'home' use, 3/8 inch air hose is usually OK. Some low air flow tools may be OK using short lengths of 1/4 inch air hose. Some bigger air tools (like a 'big' air impact wrench, or a spray booth or a media-blaster) may need or benefit from 1/2 inch air hose and fittings larger than 1/4 inch.
An 18 gauge air nailer? Not too critical on flow rate, just set the air pressure to what the tool/manual says (usually 90 psi IIRC). Again, don't use an 'excessive' length of skinny air hose though.
Want to read up some more about air tools and stuff? Read over on the TP-Tools website
http://www.tptools.com/
especially the Tips/FAQ section
http://www.tptools.com/lp2/Tech_Notes.html
Also the IngersollRand air tools site
http://www.ingersollrandproducts.com/
and their Tech Pubs site
http://www.irtechpubs.com/
Or
http://en.wikipedia.org/wiki/Air_compressor
http://www.popularmechanics.com/home/improvement/energy-efficient/1275131
sickboy motors inc.
Well-known member
Great explanations! I was going to attempt the same but really found this thread informative! Thx guys!
Hello,
I was wondering since I got a small 6 gallon 120v pro force air compressor that has the electric motor built in with the pump that is not functional but the air compressor tank is, am I able to change it to what a friend of mine gave me with a belt driven pump and electric motor?
My friend gave me a setup of the electric motor the belt and the pump which is the same as the one in the picture on the link below.
Last edited: