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Hi all. Last Christmas my dad bought me this Craftsmen tire care kit that included a 1/2″ impact. I had been saying how I want a bigger air compressor and air tools. Last summer, I did use the impact once with my 3 gallon compressor. It was just enough to remove a nut from a pulley on the lawn mower. I also used it to put it back on. About 2 months ago, I bought a nice big 21 gallon compressor and 50′ 3/8″ hose from Harbor Freight. I know it’s not the best brand, but I’m not running a shop, just my hobby stuff. Last weekend, I sat down to do my brakes and busted out the impact. I found that at 120 PSI, the impact would not even come close to loosening the lug nuts. I broke them loose with a 4-way wrench with little effort. Without any load the impact spun fast and free. But I could hold it in my hand with little effort and that would stop it from spinning. The socket did jerk back and forth with the hammer inside, but it had not inclination to rotate.
After reading my little manual that came with the impact gun, I found three possible causes:
1) The hose is too long. 25′ is the recommended length.
2) Not enough oil in the air inlet. I put in two drops to start, but added a few more for good measure. It didn’t help.
3) Not enough oil in the hammer. I added maybe a 1/4 ounce of oil in it, still no help.The only thing I can’t try is the hose. I only have the one large hose. I did swap back to the 1/4 hose that I used last summer on my 3 gallon compressor. That compressor and hose was enough to loosen a bolt before, but that hose with the new 21 gallon compressor didn’t make a difference. The only thing I didn’t try was busting out the old 3 gallon. I didn’t do that because I’d wasted a lot of time already and needed to get to my break job.
So what I’m looking for is some suggestions of what to look for. I can’t verify that my new compressor is good as this is the only air tool I have. I can buy another hose, to test with, but it seems odd that it worked last summer with a little 1/4 plastic hose. Any ideas?
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Check to see if there is a torque setting on the impact gun. You may have it set to the lowest torque and need to set it to a high torque.
Yeah, reverse is full torque, and I flipped through the forward ones when I was holding it. Honestly, it didn’t take much effort to stop it from free spinning.
I would first verify the air pressure at the end of the air line. you can p/u a pressure guage from h/f and a quick connect so you can attach it to your air line ( I did this to verify the air pressure at the end of my air line as my compressor lives in a storage shed 100 feet from my work area ) with a 3.5 hp compressor – 20 gallon tank I have well over 100 psi at the end of my air line ( 3/8 ” hose ) what is the torque rating for the gun you are using ? perhaps the gun is under powered. if you want a 1/2 inch impact that packs some serious punch check out the earthquake from h/f ( 700 ft lbs reverse ) I have had one for about a year and love it. on sale and with a coupon – out the door for 70.00.
Another thing to consider is what SCFM and pressure is supposed to be used with the Craftsmen impact gun? Does the compressor supply this or is it supplying something lower?
Funny, I just typed all this and the forum spit it back out
“Your session has expired. Please log in again.”Allow me to summarize.
Compressor puts out 4.7 CFM @ 90 psi
Impact needs something like 3.7 @ 90
Impact is rated for around 400 ft/lbs (http://www.sears.com/craftsman-6-piece-tire-maintenance-kit/p-00916861000P)Air pressure at the end of the line is a good point, I will have to try and test that. However, with the regulator fully open, both gauges read the same pressure at the start. Maybe I should put the impact gun right into the chuck on the compressor?
Other options I thought of was to buy the 1/2″ hose for a test, or to buy a second gun just to test (return when done). I just don’t have enough tools to narrow it down.
Personally, I would say you will be fine if you use something bigger than 1/4″ hose. 3/8″ hose seems to work pretty good. You need to try to get a decent volume of air to your gun quickly or it wont work as well. Try taking your impact to someone else’s air compressor setup and see how it does, if it works ok, you know its your setup.
In the first post I listed that I am using a 3/8 hose. The comparison was that I used a 1/4 hose before with success, but now neither 3/8 or 1/4 seem to provide any power.
One addition. It is pretty cold here. My garage hovers around 35-40 degrees. All the same, the PSI is still up there.
I played around more today. With the regulator open to 120 PSI, and a 3/8 hose, I put a lug nut on the car with the gun in full torque mode. Using my beam-type torque wrench, I’d say it only took about 30 ft/lbs to start turning it. I plugged the gun directly into the chuck on the tank. It still couldn’t spin out of my hand. I think I’m going to just buy another an see if this is just defective.
[quote=”Buggsy” post=41952]I think I’m going to just buy another an see if this is just defective.[/quote]
Did you ever figure anything out with it?No, not yet. With Christmas, I’m not going shopping for another couple of weeks. Digging through Sear’s website, I find conflicting info about this impact. One description says that it only needs 3.7 CFM, and another says 5.2 CFM. My compressor only puts out 4.7 CFM. Even with the impact in the chuck on the compressor, I can hold it still. I also figured out that often, when I press the trigger I just get a rush of air and no movement at all.
I might just grab one from Harbor Freight or Menards. Sears is only at the mall, and it’s not a place I want to go to right now.
HF Earthquake 1/2 impact is good. can usually pick one up for less than $70. Craftsmen tools are sold at places other than just Sears now.
Usually Impact guns dont use that much air, and even if you are only putting out 3 cfm and it needs 5 cfm, the issue you will run into is performance degradation after you use up all the air in the tank (i.e, take one or two bolts off, wait for the tank to fill up, etc). Can you run other air tools ok? Usually impact guns run good on just about anything, so if you can run an air ratchet or an air hammer fine, then I would think the impact is just defective.
I’ve been looking at the HF EarthQuake too, but it’s a bit more than I need. I tend to get a little carried away when I want to buy tools. Like I was looking at a pressure brake bleeder, but in reality, my wife can pump the peddle just fine 😉 I might still get the Earthquake. I do like to buy my tools just once.
I know that Kmart (locally) has craftsmen, but the didn’t have air tools when I was there last weekend. Oh well. I can’t think of anybody else locally. I’m not tired to the Craftsmen brand name either, but most of my hand tools are Craftsmen, so I do lean that way.jthomsonmain, this is what I thought. I used this impact, successfully with my little 3 gallon compressor last summer. I put it back in it’s box and back in the drawer. Now it’s shot :/ I do see that the ones one line show a 2 year warranty. It was a gift, so I don’t know how I’d prove the time frame. I don’t own any other air tools. I’ve wanted them for a long time, and I finally got a deal on a compressor. I know that I have a 3/8 air ratchet under the tree and maybe a 3/8 impact too 🙂 So in a week I can compare.
So related to that, why do we call it an air ratchet, when it’s not actually “ratcheting”?
It actually is ratcheting. The head of the tool actually has a ratchet mechanism in it, and if you dont have air, you can actually use it as a ratchet. If you look closely at the inner workings, the air turbine wobbles the outer sleave back and forth with an offset cam, and the ratchet mechanism in the head only allows the chuck to turn one direction. Pretty cool to take some of these air tools apart, just have fun getting them back together!
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