Air Compressor Pressure

Did you mention how many cfm the tool requires? I suspect that is the real problem. If so, cranking up the compressor pressure won't help much.

The tank pressure will cycle; the lowest pressure should be about 5-10 psi above the tool pressure requirement, to allow for pressure drop through the air line and regulator.

The tool requires 100 to 120 psi to operate , but I have run it at 130 when using a lot of clamps on larger projects.

Would this set up keep a more even pressure on the tool?

The tool should have on it's nameplate the minimum and maximum pressures allowed. If you exceed the max. you could damage the tool. It does sound like the compressor is short cycling. This could be because it can not supply enough volume of air to operate the tool. The tool's nameplate or manual should give the required amount of air in SCFM (standard cubic meet per minute). If you were to go to your local "big box homecenter" the displays in the tool section will show how many, and what type of tools each type of compressor will operate. The tank size is also important, a larger tank allows a great volume of air to be stored, which allows the compressor to run less often.

Does this new compressor have the same SCFM @ PSI rating as your old compressor?

It has the same PSI rating but the smaller tanks do not hold enough air.

Looking at the drawing I posted, I can install the compressor to the old tank ( minus the compressor on top). I do not need portable.

I do like the quieter running of the Makita, just not the amount of air those little tanks hold.

Will pig tailing it to just a larger tank, keep me with a more constant 100 psi-120psi pressure for longer working times?

More volume is good. Gives you a bigger cushion.

Lynn,

So if I can figure out how to hook up the old 15 gallon tank to this new compressor, I should be in better shape?

Do I need a pressure gauge on the 15 tank or not?

Yes. More volume smooths out the demand on the compressor.

You don't need any more gauges.

Dial the pressure up to the max. That's about all you can do.

There is one other thought. Shorter, larger diameter supply hoses will give better performance.

That's about it.

Lynn,

I've got a 5/8" hose on there now but I've got 100' feet of it. I only need 50 or less.

Good idea on shortening the hose length.

The other compressor was a gift from someone we took in after Katrina. They bought it for me and I never really looked at the details on the back. It was much bigger in air volume.

However, it drew a lot of amps. It was extremely noisy to the point of being painful when we used it.

This one runs quietly but does not seem to hold enough air. waiting a second or two is OK but I am used to making that clamping gun hit at a rapid pace. I'll strip the old compressor down and see what it takes to just use the tank as an extra storage.

Thank you and the rest of the guys again..........

Happy 4th of July

I salute your generosity and caring for taking in someone in their time of need.

You will want to connect all 3 tanks together for the maximum possible volume [storage capacity] before the regulator.

possibly make the connection where the makita tanks are connected together

you should be able to adjust the pressure switch so the pressure doesn't drop as low, before starting the compressor.

probably can't do much more maximum pressure without tripping the blow off

PLEASE, read posts #1 and #4 they are telling you to check the CFM (Cubic Feet per Minute volume of flow) that the tool requires vs the capacity of the compressor! This is at least as important as the pressure. It is like electricity relative to Current (Amps) and Voltage. If you were using an electric tool that needs 20 amps (amount of flow equivalent to CFM) at 120 volts (equivalent to PSI pressure), you will blow a 15-amp fuse every time you trigger it.

The larger tank will allow for a temporary storage of the necessary volume (similar to a capacitor in electricity), but you will have to "recharge" it every once in awhile. The larger the tank, the more shots you get from your tank with each charge cycle.

The tool is old, really old. It has nothing on the side plate but 1/4" closure ( which is how tight the ring closes.

I have been running it for years at 110- 120 and it hits hards and closes tight.

netmaker, yes, using the old tank as a volume buffer would certainly solve your short cycling issues, what you will be trading off is the run time for the compressor, instead of lots of short cycles, you will have fewer long cycles.

Add the extra tank. The pump will bring it to 130 and stop. When you start to use it you will be able to clamp repeatedly and fast for a while. In time, the tank pressure will slowly fall and it will take a while to top up.

It depends on how much air each clamping operation consumes. If the pump cannot pump it in as fast as your clamping draw it out.

With the right sized tank you can complete each series of clampings, get the new workpiece in place and hopefully by then the tank is topped up

If not larger compressor or larger tank.

the compressor is the limiting aspect, with a 1000 gallon tank, the compressor will take a while to fill it, and may run for days the first time.

Second problem, is that little makita rated for that duty cycle? It may fail after some weeks.

Now makita is better than Chinkita, but that makita may be made in China = Chinkita, it may not take the load.??

A lot of these cheap hobby tools made in China soon break, but they are good enough for the occasional user.

The pressure is to a large extent "irrelevant" in this case. The important factor is the volume of air available for use @ a specified pressure. The pressure is important for the power to close the clamps, but you need significant volumes of it. Check the SCFM requirements for the tool. Only then can you be sure to know what you've got. The compressor suplier should have informed you from scratch whether his product could do the job. If the machine rating is 40 psi @ 4.8 cfm, you definitely wont get far. If it was 4,8 cfm @ 90psi, you would have a better chance at success

Your comment that when you get going the compressor just runs and runs suggests the compressor is too small.

You MUST understand the difference between pressure and volume. You can crank it up all you want, but if the compressor will not produce the desired volume, thus it won't run very long. Larger tanks just delay the inevitable. You will only get the number of clamps per hour that the volume of the compressor will produce. You can add tank capacity for the whole hour, but you'll just have to wait another hour to catch up. Your compressor isn't big enough!

And, Yes, the re-charge cycle time will be longer than the sum total of elapsed time of air discharged per trigger pull.

The extra time is related to both the tool's required CFM versus the CFM capacity of the compressor, and the compressor supply pressure versus the tool's required pressure. Of course, you realize that this pressure ratio MUST be greater than one (1). Likewise, the ratio of compressor CFM to tool CFM should be greater than one. Apparently, this is where your true problem is. That is, your compressor is not big enough!

However, rather than scrapping your existing compressor in favor of a larger one, you may be able to save some money by purchasing another identical compressor. Hook the two up in parallel to double the CFM discharge of your air supply for this tool. Then, at some later time, for a different tool, if you need higher pressure at a lower CFM, you can hook them up in series to double your PSI at the base CFM capacity of a single compressor.

you can hook them up in series to double your PSI at the base CFM capacity of a single compressor.

Now that may well be a risky thing to do. Something might break

This Makita 2.5 hp. is just too small. Tank or no tnak, the compressor still just runs and runs. I called the store and the owner said he was not aware that the clamping gun used so much air volume to operate. He is going to take the compressor back and fix me up with with a larger one . This time though, I am bringing the clamping gun with me to make sure the new compressor does what the old one did.

I did notice it decreased about 2 psi on the gauge every shot. At around 90 psi the rings were sliding on the line instead of biting into it. They went from a 1/4" closure to almost a 3/8"....in about 6-8 shots. Pa bon! ( No Good)

Thank you all for your input .......you may never know how much good you do for a small operation like mine to be able to get this kind of advice.

nm

You are very fortunate with your dealer!

My experience has always been, tough luck, we can sell you another, or our restocking fee is 50%.

This is the very Deep South and folks tend to be a little more easy to work with.

If they want the business next time, they need to keep a good reputation.

It's very simple - the compressor is undersized. If you need 120psi and the compressor can only reach 90 psi when you are operating the air tool then you are using more volume of air than the compressor can produce at the required pressure (120psi). Return the compressor to the dealer and buy a larger one.

My new 3 gal air compressor will not keep a consistent outgoing pressure. For instance, I turned the regulator to read 60 psi. It stays at 60 while I'm using it until the unit kicks on, then the outgoing pressure will reach 125 psi which is the same as the tank pressure when the unit shuts off. Any help will be greatly appreciated.

Your regulator is hosed.