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Impact Driver Versus Impact wrench

Rich M.

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Getting older so I thought it is time to look at impact tools. Tired of hand watching fasteners. I mainly work on fixing push lawn mowers as more of a hobby and to help out family and friends. My question is should I buy an impact driver or an impact wrench? Most of the fasteners are 10 or 12mm nuts. The the blades are normally 14 mm and about the same for a flywheel nut.

I know drivers are not really for removing nut, but it can be done. I ask because most of the Youtube engine repair people seem to use a driver to remove fasteners. Is it because a driver is easier to handle when dealing with small engines?

I guess I could buy a battery driver and an air impact wrench, but it seems like an expensive over kill and a waste of money.
 
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GeoBruin

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You, lose some torque by putting a hex to square drive adapter in an impact driver so you can use sockets but for fasteners in the range you're describing, you'll probably still have plenty of power. The ability to spin the billion other things that use a 1/4" hex drive can not be oversold. If I could only have one, I would get the impact driver.

Good luck.
 

cmandp

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A impact driver I usually consider to have a 1/4" Hex drive (they make other size like 7/16" for industrial applications) and be used to drive screws (Wood, sheet metal or even machine screws). An impact wrench has a square drive made to take sockets directly. You know they make 1/4" hex to square drive adapters which work but you can loose a lot of the impulse through the little 1/4" shank.

For working on lawn mowers the driver would probably work for most things but I doubt it would work on blade nuts or anything higher torque like that.

I have a Milwaukee M12 3/8" impact wrench which I use for automotive stuff but it was a compromise for me. I wanted it to be used for automotive work with sockets first and screws/woodworking second so I have a 3/8" to 1/4" hex adapter. Lately I've been doing more woodworking than automotive work so I've really been driving screws which is not ideal with the wobble from the adapter.

So what I'm trying to get at is: For screws you really want a driver for minimal wobble with bits (Phillips, square, torx, small hex screws, etc) and for bolts you would use sockets on you really want the wrench. Hopefully my babbling helps you decide which you think would work best for your use. Or the Garage Journal answer: You could just get both :p.
 

Notbn

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If you have to get only one, and you do DIY jobs around the house in addition to small engine repair, I'd go for the 1/4" hex impact driver. As others have said it is slightly more versatile. Be prepared for it to not take everything off though, some of the more stubborn blade or crank bolts might need a little more oomph.

If money is not an issue, get both! The right tool for the job in this case is a square drive impact wrench. I'd go for a stubby 3/8" in your case as it will probably have more than enough power for anything small engine related.
 

engineer2

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I use my Makita impact driver to service my lawn mower, plus for vehicle lug nuts. Lawn mower blades with a 9/16" head are not a problem.
 

BlakeTheCarGuy

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The impact driver will be ok for bolts not torqued down as tight but it won’t take off the tight ones till you break them loose. An impact gun will. I’m always for air impact over power but that’s just me I feel the air is much, much more powerful than a battery powered one.
 

sweet victory

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Instead of running a 3/8 adapter on an impact driver you could get the M12 Stubby 3/8 impact, and run a 3/8" drive to 1/4" hex adapter.
 

joshmodelskidoo

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for your use a name brand impact driver is my vote. love my cordless impacts, probably my most used tool. dewalt or Milwaukee is your best bet but check them out in store. milwaukee m12 handles are pretty thick and not suited for all hands so thats why i say to check them out in the store
 

Torque Test Channel

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From top brands, we see similar torque from the best impact drivers as we do from cordless compact impact wrenches. But you'll be breaking a handful of those square drive adapters along the way if you use all that torque. We go through 1-6 an episode currently.
 

jayemm

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I had a milwaukee 12v 3/8 impact wrench (non Fuel). Didn't seem as powerful as I thought it should be. I wished I would have spent the extra for the Fuel version for more torque. Got rid of it and have a Makita impact driver (18 v, brushed) that is more powerful and even with a socket adapter will loosen lug nuts torqued to 90+ ft lbs. I would not go with anything 12v even for your purposes. Just my experience.
 

Professional Tool User

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An impact driver is perfectly adequate for low torque applications. Just keep in mind that the adapters are wear items, especially in 1/2 dr.
 
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Rich M.

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As far as blade bolts, most push mowers’ blade bolts are only torqued at about 42 lbs. so breaking a blade free with a driver should work in theory. Not planning on tightening any bolts that requires torquing. Will use a torque wrench.

I am guessing with Father’s Day just around the corner, I might find a good package deal somewhere. Not sure if Memorial Day will bring ay good package deals, but I will look.

Has anyone had good luck using hex shaft drive nut sets with their impact drivers?
 

brcarls

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Everyone is missing or glossing over the fact that an impact driver and an impact wrench operate in a fundamentally different way (which is right in the name of the tool). The 1/4" hex vs square socket drive is just a minor detail that does not define the nature of the beast.

The big difference is that an impact driver imparts a forward hammering impact as well as rotational impact at the same time. This helps to keep a screwdriver bit engaged with the screw by only rotating the bit when it is being hammered forward.

An impact wrench imparts primarily a rotational impact to provide a torque impulse. There is no need for a forward impulse like a driver so that would just waste energy making the tool less efficient (i.e. an impact driver with a forward impact would need a much bigger motor for the same rotational torque rating as a normal impact wrench).
 

GeoBruin

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I think you may be confusing an impact driver with a hammmer drill. There is no axial impact imparted by an impact driver as far as I am aware.
 
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dungeoncrawler

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The big difference is that an impact driver imparts a forward hammering impact as well as rotational impact at the same time. This helps to keep a screwdriver bit engaged with the screw by only rotating the bit when it is being hammered forward.

They absolutely do not. Impact drivers and impact wrenches operate on identical principal and besides sizes, are near as to be the same inside. The only tools that impart forward hammering motion are hammer drills and jackhammers.
 

rancherbill

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Impact driver, on those size nut you will be breaking everything with and impact wrench.

My Driver is Makita and it has 1440 inch pounds of torque ( 120 foot pounds). You can put it on 1/4 bolt and easily break them.
 

dungeoncrawler

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Impact driver, on those size nut you will be breaking everything with and impact wrench.

My Driver is Makita and it has 1440 inch pounds of torque ( 120 foot pounds). You can put it on 1/4 bolt and easily break them.

Depends on the wrench though - a lot of the newer wrenches (as well as drivers) have speed settings that limit the torque, and Makita and a few others also have "autostop" for when the bolt gets broken loose or snugged hand tight. They got quite advanced in the last couple of years,
 

brcarls

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They absolutely do not. Impact drivers and impact wrenches operate on identical principal and besides sizes, are near as to be the same inside. The only tools that impart forward hammering motion are hammer drills and jackhammers.
I think you may be confusing an impact driver with a hammmer drill. There is no axial impact imparted by an impact driver as far as I am aware.

No confusion... I have taken apart an old Ridgid and there is a spring loaded hammer that absolutely imparts a hammering force.

Edit: You folks seem so confident that I thought maybe I'm wrong about modern impact drivers... so I did a quick test with a somewhat new makita. I grabbed the bit with a pair of vice grips so that it couldn't rotate and pressed it against a piece of steel flashing... it instantly hammered a nice little dome into the flashing. I even attached a photo attempting to show it.

So, 100%, absolutely, no doubt about it, my Makita impact driver hammers with an axial force.
2021-05-21 16.52.34.jpg
 
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GeoBruin

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Watch this video. You are correct in that the hammer must retract axially to clear the "teeth" with which it engages on the chuck, and it is indeed assisted back forward by a spring which probably imparts some nominal axial force, but that is a byproduct of the primary function (rotational force) and it is exactly the same mechanism in an impact wrench.

Contrast that with the mechanisms used in a hammer drill or rotary hammer which are designed to impart an axial force.

 

Torque Test Channel

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<- We might know a thing or two about impact tools

The ball and cam design of a cordless impact mechanism uses a spring as a byproduct of it being a cordless tool and electric motors not liking being stopped suddenly and completely, therefore they use that spring to sort of wind up and push that hammer cage back for another half a rotation before it falls (the force you're seeing forward) down onto the next lobe of the anvil in rotation. Otherwise the mechanism is almost identical to a pin-clutch like on a 1250-K.
That spring winding is what you feel on your arm and body and why cordless beat you up unlike air, cuz of that newton's equal and opposite law business.
They are not designed to impart forward impact blows, it's merely a byproduct of an unavoidable design.
 

brcarls

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They are not designed to impart forward impact blows, it's merely a byproduct of an unavoidable design.

A very happy accident it seems.

I always take the rest of the day off when I learn something new... why couldn't we have had this exchange in the morning instead of after 5 on Friday?
 

PossumDog

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Has anyone had good luck using hex shaft drive nut sets with their impact drivers?
Yes, I use standard 1/4 - 1/2 hex nut driver bits all the time. Bits and driver from harbor freight. Agree w previous replies that driver is handier around the house. It's possible large stubborn bolts you might have to break free by hand and then use the driver to zip them off.
 

vavet

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Ok, first of all, when the torque test channel get here? I feel like I’m in the presence of greatness, love your channel!

secondly...for the OP...when you’re saying 10, 12, and 14 mm, is that the wrench/socket size? Or the fastener size? For push mowers, I think you‘re talking about the wrench size. If so, then a impact driver is going to do most of the work you need. Even if you have to break a few fasteners loose here and there, they can still speed them out for you. A 10mm bolt has a 17mm head, iirc. You’re probably going to use an impact driver to break that loose.
 

ChevyEFI

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If you want a tool that acts like a light-duty impact gun, but drives 1/4 hex, look into the Fuel M18 (*not surge*) Milwaukee with adapter, or Bosch freak with 1/2" sockets or 1/4 hex. Neither is going to be a super heavy hitter. For taking little stuff apart, both will work. The Bosch will take M12 and M14 lug nuts off my vehicles, torqued to 130lb-ft.

If you want to break "stuck" and "rusty" stuff free with more muscle to it, step up bigger.
 
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Rich M.

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I picked up a Dewalt DcF 885 at a moving sale. The guy had tons of Dewalt items. He sold me the impact driver for $5. Turns out he worked for Stanley for 25 years. Unfortunately he did not have any batteries for sale. He did have one so I could test it out. He sold me the charger for another $5. Just need to start looking for who has the best price for batteries. For the little use that I will need, a 1.5 ah should work just fine.
 

Neggy

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I would not want to be using an impact DRIVER on a bolt in a crankshaft (lawn mower blades) as you are also hitting the shaft and thrust bearings

Kind of the reason you are not supposed to beat a harmonic balancer onto a crank snout.... use a puller/installer to do it right

I bought a M12 Stubby with a 1/2" anvil for the shop, I bought it to put tires on, as our air impacts bring the lugs over torque, so the M12 was a nice way to get things back together before torquing.... I liked it so much I bought one for home use even though I have the M18 high torque and another M12 impact.

When I got back from my winter hibernation in FL my partner had taken to using the M12 stubby for general use.. and it has held up real well.
 
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