Impact wrench low air output

I had some lug nuts I needed to get off my dump truck rear tires so I purchased an electric impact wrench that was rated for 220 ft lbs. With many passes, only 1 out of 10 came off so I decided I needed more power (and a great excuse to buy another tool!). So I purchased another impact wrench but this one was pneumatic and rated for 550 ft lbs - sure to do the job right? Nope! It actually seemed to have slightly less power than the electric one! My air compressor is just a small pancake type and goes up to a maximum of 150 lbs of air pressure. When I use the wrench, the compressor air level goes down real quick and kicks on within about 3-4 seconds. The torque immediately goes down too in proportion to the amount of pressure in the tank.
Just for clarification, the outlet pressure has been adjusted to put out its full capacity.

This brings me to some questions: Is the wrench not putting out the full 550 ft lbs of torque for more than maybe a half second due to the small storage of the tank? Will increasing the size of the storage (lets say by using one of those portable tanks or even a converted propane tank) do the trick?  or..... do I just need a bigger air compressor to do this kind of work?

Its rare that I need this much torque power for a one time job (hopefully) so although a large fancy air compressor would be nice to have, I would prefer to keep the cost down.

Any suggestions appreciated

My experience with compressors is limited to nail guns running a pallet building  business.  My guess is you need a bigger compressor and tank.  That said,  why not ask a mechanic in your area?

Yes your impact will only be running at top torque for a few seconds with limited air capacity like that. More air capacity would definitely be something to try aswell as setting your air output regulator down to 90 or 100 psi as that's what most impacts are rated for anyways and that should give you a couple extra seconds at full torque.

Hi Gerry;
The little air tanks just cannot store enough air with high running pneumatic tools. You need at the least a larger storage tank. Like 250 gal. defunct propane tank would work well.  
I Know... you don't have a 250 gal defunct tank laying around.   Well in that case use that 500 gal defunct propane tank you got... or 100's or 25's, or maybe 50, 5 gallon tanks all connected :)

Now is your baby compressor going to fill your 500 gallon tank ???  Probably ... eventually... Maybe....  How quick will your rattle gun drain that tank???  Pretty darn quick I'm thinking... Could the compressor keep up ?  Maybe but it might be like running a 63 VW beetle flat out on a drag strip... it'll go but ... not for very long.

My humble opinion...   buy a cheap 3/4 drive socket set and use a 4' cheater pipe to torque stuff.  It's much cheaper than the full size air compressor that you really need ...

Marc Dube wrote:Yes your impact will only be running at top torque for a few seconds with limited air capacity like that. More air capacity would definitely be something to try aswell as setting your air output regulator down to 90 or 100 psi as that's what most impacts are rated for anyways and that should give you a couple extra seconds at full torque.

I knew that if the air outlet is set too low, all your'll get is a little puff of air when you squeeze the trigger but what I never realized is that setting the air output between the lowest possible setting up to the maximum (150 psi in my case) would still put out a full torque but with just longer working times. Interesting.

Also for clarification, my impact wrench has a lever on the back to adjust the amount of torque needed for the job. It has 3 circles - small, medium and large. The large I'm assuming is the highest torque and the lowest being the smallest circle.

thomas rubino wrote:Hi Gerry;
The little air tanks just cannot store enough air with high running pneumatic tools. You need at the least a larger storage tank. Like 250 gal. defunct propane tank would work well.  
I Know... you don't have a 250 gal defunct tank laying around.   Well in that case use that 500 gal defunct propane tank you got... or 100's or 25's, or maybe 50, 5 gallon tanks all connected :)

Now is your baby compressor going to fill your 500 gallon tank ???  Probably ... eventually... Maybe....  How quick will your rattle gun drain that tank???  Pretty darn quick I'm thinking... Could the compressor keep up ?  Maybe but it might be like running a 63 VW beetle flat out on a drag strip... it'll go but ... not for very long.

My humble opinion...   buy a cheap 3/4 drive socket set and use a 4' cheater pipe to torque stuff.  It's much cheaper than the full size air compressor that you really need ...

Oh yeah, have definitely done the cheater pipe trick! I've actually broke 2 breaker bars this way on this project! Wacked my knee one time and my knuckles on  the other..... Cusss..cussss!

I certainly don't want to overtax my little compressor by doing more work than what its intended for (as its real handy to have around for a lot of portable jobs). Maybe a small 20# propane tank would be a good start to get a little more storage air then without much risk.

You need more storage.  That size compressor won't handle that size air gun.  You can use it for quick runs if you can add storage.  If you need it to work steadily you will need more compressor.  Good air guns are stronger than their electric counter parts.  But there are lots of cheap air guns that are far lower power than the electric.

There are guys online that obsess over air tool power, you might be able to find a test that includes your model of air wrench, see if it really provides its rated power.
But I've seen cases where borrowing a giant air compressor and impact wrench from a neighbor is still not enough. Then its time for a torch, heat the nut, fast enough to expand the nut and not overheat the wheel and tire (which can explode).

Another emergency method is cutting through the side of the nut with a flat abrasive wheel (dremel or air die grinder). Then hammer it open with a chisel.

If you want to throw money at tools, my previous generation dewalt cordless impact wrench is rated at 700ft-lbs..

Newer Milwaukee ones are good for 1800ft-lbs! Just don't ask the price...

Very handy on a larger property, often the difference between walking to the task or getting the tractor to move the generator and air compressor...

It's been my experience that ok ratchets can withstand a snipe better than cheap breaker bars, a 200 lb gorrilla on the end of a snipe beats pretty much any impact wrench 3/4" or smaller, only a hammer wrench and a 3+ lbs hammer beats the gorilla with snipe.

A little air tool oil can make a big difference in how hard an impact hits, air hose size could be a limiting factor also.

Even with the little compressor you should get a few good Dugga Duggas out of your impact

A few heatings with a torch can help, some copper kote or never seize on hand to save you or the next guy next time :)

Grady Houger wrote:There are guys online that obsess over air tool power, you might be able to find a test that includes your model of air wrench, see if it really provides its rated power.
But I've seen cases where borrowing a giant air compressor and impact wrench from a neighbor is still not enough. Then its time for a torch, heat the nut, fast enough to expand the nut and not overheat the wheel and tire (which can explode).

Another emergency method is cutting through the side of the nut with a flat abrasive wheel (dremel or air die grinder). Then hammer it open with a chisel.

I know for sure the impact wrench is not first class but will see if there is anything written up on it.
I did try a propane torch to heat the nut for several minutes but it just wasn't hot enough. If I had an acetylene torch, it may have been a different story.
Two of the most stubborn nuts I ended up doing exactly what you said, a small cutoff wheel with a dremel, then prying it open just a bit to relieve its grip on the stud which then spun off easily.

Alley Bate wrote:It's been my experience that ok ratchets can withstand a snipe better than cheap breaker bars, a 200 lb gorrilla on the end of a snipe beats pretty much any impact wrench 3/4" or smaller, only a hammer wrench and a 3+ lbs hammer beats the gorilla with snipe.

A little air tool oil can make a big difference in how hard an impact hits, air hose size could be a limiting factor also.

Even with the little compressor you should get a few good Dugga Duggas out of your impact

A few heatings with a torch can help, some copper kote or never seize on hand to save you or the next guy next time :)

- Could you explain what a snipe is? All I get from a search is a shore bird with a long beak.
- One of the breaker bars was cheap so no surprises there (in fact it said do not exceed 110 ft lbs...ooops!)
- I don't use the impact wrench that often but wouldn't hurt to add a few drops of oil to the air port anyway.
- I was using one of those short coil hoses but then switched to a straight and larger diameter one but didn't notice much of a difference.
- Yes, a few good dugga duggas is about all I get before the air decreases so much its not worth continuing until it recharges again....and again....and again.
- I did coat the threads and also the surface area that mates with the drum with copper kote too. Cause I know that next guy will probably be me!

D Nikolls,  I have often had to use the tractor to transport heavy stuff all around the property. Wouldn't be without one in the country!

A snipe in this sense is just a cheater bar that is placed over the breaker bar for extra leverage.

It is truly amazing how much torque the new Milwaukee cordless impacts put out. (They better for the price of them though).

Good Morning Gerry;
You might look at one of these, they work really really good.  https://www.harborfreight.com/20v-max-lithium-12-in-cordless-xtreme-torque-impact-wrench-kit-64195.html?_br_psugg_q=impact+wrenches     $270   with battery and charger

EDIT) Should have mentioned    1200 ft # of torque

Gerry,

When did you get your electric impact wrench?  The reason I ask is that there are some modern battery powered impact wrenches that deliver over 400 ft pounds of torque.  I am personally in the Ridgid platform and their Octane impact wrench is very impressive.  Other reputable companies also make very modern, very good impact wrenches.

Just a thought,

Eric

Here's a few things I've learned about pneumatic tools over the years. I own an array of air tools from various nail guns to impact wrenches, a ratchet and a few others I can't think of. I have two air compressors, a small pancake for portability and a 20 gallon twin cylinder pump on wheels. The psi energy of the air is only half the equation, and the other half is the scfm or standard cubic feet per minute rating found on all air compressors. Every air tool will have a scfm minimum for the tool to operate satisfactorily. Big 3/4 and 1 inch impact wrenches need larger fittings and larger diameter hose to move that high volume of air to the tool so it works right. If I have my framing nailer hooked up to my pancake compressor, I can watch the regulator needle pressure drop and take a second to recover back to its set pressure, and I can also hear the air flowing through the regulator as it recovers and recharges the tool and also the hose. Those regulators seem to me to be a choke point. If I have my framing nailer on bump fire and rapidly start shooting nails, after a few the heads of the nails start to stick up from the material being nailed because there hasn't been enough recovery to fully charge the air holding chamber in the handle of the gun. Impact wrenches are much more demanding and need continuous flow. I have used my 1/2 inch impact wrench with my pancake, but I can only just do quick pulls of the trigger to loosen a nut or bolt. It takes a while as I'm waiting for the air compressor to recover. My 20 gallon tank and pump makes all the pressure, and volume rate of flow (the scfm) that my 1/2 inch impact wrench needs. I have a 3/4 inch drive impact wrench that can torque around 1000 ft/lbs and my 20 gallon tank can't keep up. I have to do short bursts and let the compressor recover.

One more thing. Air tools won't work right and will also have a short life without air tool oil. Don't use motor oil or sewing machine oil. Use air tool oil. It's got ingredients in it that help condition rubber and other seals since oil rots rubber and also remove the water that is in the compressed air unless a person has an air dryer on their compressor. I suggest avoiding the new "oilless" tools- they don't last and are not made to be serviceable; in other words they are throw away tools engineered with planned obsolescence. The tools that use oil can have all their internal parts replaced, especially the o-rings. I've learned the hard way that 3 or 4 drops of air tool oil, while may be good for a brad nailer, is inadequate for bigger tools. I recommend generous oil applications and before each use, and also if going into long term storage. I mean squirt that shit in there, load it up, like 30 drops or a teaspoon worth for a framing nailer or small impact wrench. Pneumatic tools that are liberally oiled seal up the moving internal parts properly which makes maximum efficient use of the stored energy in that compressed air.

Eric Hanson wrote:Gerry,

When did you get your electric impact wrench?  The reason I ask is that there are some modern battery powered impact wrenches that deliver over 400 ft pounds of torque.  I am personally in the Ridgid platform and their Octane impact wrench is very impressive.  Other reputable companies also make very modern, very good impact wrenches.

Just a thought,

Eric

Hi Eric,   Actually, I purchased it less than a year ago. We have 2 Rigid drills that I like as well. Have had many free battery replacements which is nice. Will look to see what kind of torque they put out....If not, Thomas's suggestion sounds pretty impressive (no compressor and hose to drag around either).

James,  That's a lot of great information! This really helps me to see that moving towards battery operated may be the best solution all around for this application.

Gerry,

I chose the ridgid platform a long time ago (I think I had a 1st generation model).  I liked them then and they have only gotten better.  My collection includes the (presumably) 1st gen tools, gen 4, gen 5x and the current Octane generation.  I will say that the Octane generation is head and shoulders above the rest.  I got the Octane hammer drill (just liked it, nothing wrong with the gen4 it replaced) and it is full of wrist-breaking torque.

I also have a brushed, gen 4 impact wrench that will rip my arm off before giving up.  The gen5x and especially Octane ones are amazing.  However, if you get the Octane, you only get the best benefits with an Octane battery.

I love my new hammer drill and I want to acquire an Octane reciprocating saw and maybe a circular saw.  These tools would round out my collection.

I have a lot of other Ridgid power tools but I cannot justify upgrading as they already work great.

I should collect a commission from Ridgid.

Eric

Gerry, everyone,

So when I first went looking for an 18v tool set, I was seriously considering Milwaukee, DeWalt and Ridgid.  Milwaukee are probably the best tools out there and I really like them, but they are priced outside of my budget and comfort limit.  This was back in 2006 and Ridgid tools had just come to market.  With Milwaukee out of the competition, I very carefully compared Ridgid and DeWalt.  Ridgid edged out DeWalt because it was slightly cheaper (and we were counting every penny) and the batteries (old Ni-Cads) were covered for replacement (and indeed I got those first two batteries replaced for free!).

Initially I was disappointed as the DeWalt had a 5 piece plastic molded hard case whereas Ridgid only had a soft canvas case that barely fit the tools.  But really, this was trivial.  

As the years went on I was increasingly pleased with my choice in Ridgid.  When Ridgid transitioned over to lithium ion batteries, the mating format remained the same, meaning old batteries worked on new tools and vice versa.  I did not have to change battery formats.

I did smoke two tools.  My fault on both.  I really overused a 12v right angel tool and I tried to use my gen 1 Hammer drill with no thermal cut-out to operate a 6” hole saw—on the high setting!  I bought a gen4 reconditioned replacement on eBay for about $75 and it still works great.  I did get the Octane hammer drill because I wanted still more torque for a couple of specific applications and I personally love the chuck light as I get no shadow when drilling.

I still have a gen1 reciprocating saw that works fine but I would like an orbital function and led light.  I also have a 6.4” left sided circular saw that also works well and gives me a good view as I am right handed.  I would like to get a true 7.25” circular saw and I have heard good things about the Octane.

One other tool I have worth mentioning is the gen5x Stealth Force impulse (not impact) driver.  The nice part of the impulse driver is that it yields up a considerable amount of more torque than an impact driver all while giving off about half the noise.  That last part really matters.  At the moment the impulse driver is discontinued, but I am hoping that it comes out in an Octane version.

I think that ridgid is well positioned for the enthusiastic weekend warrior/prosumer market (that’s me by the way).  It compared favorably to Milwaukee but at 2/3 the price.

In case you can’t tell I like the Ridgid line.  I guess I am a little biased there.  But I have watched head-to-head comparisons with Milwaukee and when Ridgid looses, it is usually by fractions of a second.

I think that Ridgid is in the ideal bang/buck zone.

Eric

Gerry,

I just checked the Ridgid Octane impact wrench.  When paired with an Octane battery it pumps out a whopping 625 ft-pounds of breakaway torque!  I would say if that can’t get the job done you have a very serious problem indeed.

Eric