Tool ignorance - impact & compressor

[bonzoscott]

I was hoping folks could help me understand. I have an old Snap-On heavy duty impact. Feels like it weighs 6 pounds. I have a regular Craftsman 20 gallon 110 psi compressor. Some of the most difficult nuts I like to use the impact for, like say your car lug nuts, the impact is not so effective. I would have to break them loose first. I'm guessing impacts wear out. I oil it before every use. Can they be "refurbished" by the common shade tree mechanic? OR do I just need a bigger compressor? Thanks....

 

[dingbat]

Re: Tool ignorance - impact & compressor

What is the compressor rated at in CFM? What is the wrench rated at? How big and long is the hose your using? If any of theses are mismatched the result will be less than optimal

 

[superbenk]

Re: Tool ignorance - impact & compressor

Sounds like an undersized compressor. Sometimes compressors have a psi adjustment valve that controls how much psi is sent to the tool. If that's cranked down too low it can affect the performance if the tool significantly.

 

[bonzoscott]

Re: Tool ignorance - impact & compressor

Thanks for the replies guys. I will look into things as I know nothing about them. The adjustment / regulator is topped out at 110 psi and it's a 50 foot hose. I kinda leaned towards small compressor idea, but didn't want to invest in a new one if I found it is just a worn out impact.
Oh yeah, another clue maybe: The impact kinda chucks along slowly with out squeezing the trigger. If I put excess oil in it, it does not do that but it's messy.

 

[gm280]

Re: Tool ignorance - impact & compressor

I was hoping folks could help me understand. I have an old Snap-On heavy duty impact. Feels like it weighs 6 pounds. I have a regular Craftsman 20 gallon 110 psi compressor. Some of the most difficult nuts I like to use the impact for, like say your car lug nuts, the impact is not so effective. I would have to break them loose first. I'm guessing impacts wear out. I oil it before every use. Can they be "refurbished" by the common shade tree mechanic? OR do I just need a bigger compressor? Thanks....

Hard to say why your impact wrench doesn't seem to work properly. I have a Craftsman impact wrench and it removes a lot of completely stuck bolts and nuts and wheel lug nuts are a piece of cake to remove. Now my neighbor has two impact wrenches and he can't get either one to work at most any removal effort and his compressor it a huge commercial unit too. He was amazed that I could remove wheel lug nuts so easily. I have a 4.5HP portable compressor but the max air pressure has more to do with capability then the total CFMs. Even a little pancake compressor will allow you remove stuck bolts and nuts. It will give out sooner, but the initial force will remove them or loosen then. So maybe you need to rebuild yours. They do make rebuild kits for them. Just a thought!

 

[bonzoscott]

Re: Tool ignorance - impact & compressor

Just had a thought: Maybe I could take my wrench to one of many tire shops & see if their top end compressor with my wrench breaks lugs. That may rule out the wrench... huh? My compressor works well for most things.

 

[Bob_VT]

Re: Tool ignorance - impact & compressor

Yes impact wrenches wear out and there are rebuild kits for them to replace the vanes and seals. 110 PSI should work fine. I run 125 PSI and works fine.

 

[LongLine]

Re: Tool ignorance - impact & compressor

Ditto - you need a rebuild job.

Tom B.
(LongLine)

 

[rbh]

Re: Tool ignorance - impact & compressor

Can you hear any air leaks coming from the tool when its just sitting?
Is there a adjustment dial on the tool? some guns have a dial/knob that cuts down on the torque the gun delivers so you don't snap the heads off bolts.

 

[82rude]

Re: Tool ignorance - impact & compressor

3/4 drive snap-on .800foot lbs in rev .works all the time,lol.on my old 3/4 ton the regular impact wouldn't do the trick either.came upon a screaming deal on the 3/4 snappy and it takes care of the lugnuts like their all ready loose.not for everybody or every situation but comes in handy once in a while.

 

[NewfieDan]

Re: Tool ignorance - impact & compressor

Your biggest clue is that you said it kind of "chucks along slowly even without pressing the trigger". To me, that says its rebuild time. Sounds lime air is passing within the tool itself. A re build should fix it.

 

[minuteman62-64]

Re: Tool ignorance - impact & compressor

Yeah, they get old and need rebuild. Your compressor should do the job, just won't supply enough air for an extended duty cycle. Don't know what the cost in time/$$ is for rebuild or how much you use yours - but I'd take a look at HF. Get one for about $50, use it till it wears down, get another.

 

[bruceb58]

Re: Tool ignorance - impact & compressor

I have a 4.5HP portable compressor but the max air pressure has more to do with capability then the total CFMs.

Ditto.

The CFM of the compressor has nothing to do with how the tool works assuming the pressure is really at 110PSI. The CFM comes into play when you are using it a lot!

If you are using a very long hose and it is a small diameter, you could get a pressure drop that could affect you.

Using your tool without lubing it first and not using a water separating filter will hurt your tool over time.

 

[MTboatguy]

Re: Tool ignorance - impact & compressor

I have literally had impacts blow up in my hands, the last few that I have bought have been from Walmart for about $20, I use them until they die and then go get another one, it is amazing how many small little parts are inside of those things, A SnapOn or Mac might be worth re-building, but I don't worry about it, for the cost of one of the big boy toys, I can buy a dozen cheap ones. One thing I will add, I do have a 70 Gallon/10hp compressor. I have a lot of spare air to keep things going, my 5 gallon, is continually cycling if I try to use the impact, take into account, most of the time, I am using the impact to take lugs off that are an 1 1/16 in diameter, on the dually.

 

[coolbri70]

Re: Tool ignorance - impact & compressor

the snap on rep can fix it

 

[nwcove]

Re: Tool ignorance - impact & compressor

i have a 1/2" electric impact gun, no issues removing lugnuts. i think it specs at 300ft/lbs. it was much cheaper than upgrading my tiny compressor!

 

[bonzoscott]

Re: Tool ignorance - impact & compressor

Thanks again for the insight. I will look into rebuilding. Like I said, know nothing about them (or compressor). Yes, It does leak air while setting. It's got alot of miles on it.

 

[dingbat]

Re: Tool ignorance - impact & compressor

The CFM of the compressor has nothing to do with how the tool works assuming the pressure is really at 110PSI.

Boyle?s Law states, ?At a constant temperature, the volume of fixed amount of gas (air) is inversely proportional to the pressure?.

Volume is inversely proportional to the pressure but the deliverable "volume (of the compressor) has nothing to do with how the tool works"?

Pressure drops in new pneumatic air lines:
dp = 7.57 q[SUP]1.85[/SUP] L 10[SUP]4[/SUP] / (d[SUP]5[/SUP] p)

dp = pressure drop (psi)
q = air volume flow at atmospheric conditions (CFM)
L = length of pipe (ft)
d = inside diameter of pipe (inches)
p = initial abs. pressure ([SUP]psi[/SUP])

There is that ?volume has nothing to do with how the tool works" in another sizing calculation. :lol:

dp = 1/2? dia. x 50? lg., x 110 PSI = 1.45 psi
dp = 3/8? dia.x 50?, lg. x 110 PSI = 6.9 psi
dp = 1/4? dia x 50? lg. x 110 PSI = 46.26 psi

 

[bigdee]

Re: Tool ignorance - impact & compressor

i have a 1/2" electric impact gun, no issues removing lugnuts. i think it specs at 300ft/lbs. it was much cheaper than upgrading my tiny compressor!

I got one of those electric ones from HF on sale for $40. It will blow my 1/2" ingersol-rand air impact gun away. The only disadvantage is its size and weight makes it a little bulky but it gets the job done.

 

[coolbri70]

Re: Tool ignorance - impact & compressor

my impact gun breaks nuts loose at home with a 1 gallon tank portable compressor it dies fast but still works, yours needs rebuilt, the snap on rep will have a kit to rebuild it, if he is like my rep he may even do it for you, no charge