Do 12v impact drivers deliver their stated torques?

[stickshift]

I'm looking at the Makita 10.8v (12v max) impact driver model TD090DW (part of a combo kit on Cyber Monday special). It has a max torque of 800 lbf-in, or 66 lbf-ft.

Is that enough for most DIY automotive work, save for lug nut removal/tightening? Seems like a lot of bolts larger than 14mm (from reading up a bit on impact drivers, 14mm seems like the largest recommended for 12v impact drivers) don't require torque in excess of 800 lbf-in, assuming of course that the tool can deliver this torque in real life applications.

 

[Danglerb]

Not in my opinion. I have a Bosch impactor and it "technically" should be able to break a M10 and it won't break one loose.

 

[rlitman]

I absolutely love my 12V Bosch impact driver, but don't use it on my car. My $20 3/8" pneumatic impact has at least double the power, and is fine with sockets, but an impact driver, driving a 1/4" hex loses so much power in that square drive adaptor that a 12V is not really worth it for machine screws over 1/4" (ok, maybe 5/16", but that's pushing it).
So, I'm thinking M6 or possibly M8. M8 uses a 13mm socket iirc, so yeah, you're in the ballpark, but there's no way my Bosch could remove my brake caliper bolts (as an example), and those use a 14mm socket.

 

[diesel research]

I absolutely love my 12V Bosch impact driver, but don't use it on my car. My $20 3/8" pneumatic impact has at least double the power, and is fine with sockets, but an impact driver, driving a 1/4" hex loses so much power in that square drive adaptor that a 12V is not really worth it for machine screws over 1/4" (ok, maybe 5/16", but that's pushing it).
So, I'm thinking M6 or possibly M8. M8 uses a 13mm socket iirc, so yeah, you're in the ballpark, but there's no way my Bosch could remove my brake caliper bolts (as an example), and those use a 14mm socket.

5/16 (thread, 1/2 head) is fine with my M12, even with stud threads exposed to weather. Above that it is of minimal use unless the fastener lives in an oily (but not exposed to water) environment.

 

[jjjrmx5]

I'm looking at the Makita 10.8v (12v max) impact driver model TD090DW (part of a combo kit on Cyber Monday special). It has a max torque of 800 lbs-in, or 66 lbs-ft.

Is that enough for most DIY automotive work, save for lug nut removal/tightening?

The drill/impact combos seem to come in two different capacities these days.
12v and under (usually 7.2v , 9.2 or 12v) and the 14v and up type(usually 18v, 19.2v, 20v and up any more).

The smaller voltage tools are fine for automotive trim and interior work and light underhood duty (valve cover bolts, bracket bolts,etc.). They are also good for electronics and appliances The 18v tools are fine for medium duty work like removing belly pans, body bolts and the like that are lightly torqued, but I really see them shine for construction service where you are diving deck screws, dry wall screws or lag bolts ad nauseum.

Once you get into anything in the upper range of 3/8 or 1/2 socketed nuts and bolts (M10, M12 and M14's), you really need a true dedicated square drive impact and not the 1/4" hex drive stylewith the shank adapter as it can work in a pinch--maybe, but it's really not designed for that purpose.

 

[stickshift]

Do cordless impact drivers prevent cam out on screws the way manual impact drivers (the ones you hit with a hammer) do?

With bolts, does the repeated hammering risk rounding off the bolt?

 

[jim_rush51]

I have the makita you are talking about, and it is one of the best tools i own, as a everyday mechanic. I use it for everything inside the car to the engine area. Valve covers, oil pans, trans pans, most covers and air filter boxes. with alot of brakets you have to break it loose, which some will say defeats the purpose, but breaking loose and using it to remove bolts that are long make it well worth it. I have thought about picking up a bigger model but space is usually a issue so they wouldnt help alot. The one thing i highly recomend for it is a large selection of 1/4" dr. swivel sockets. They are a godsend when using that thing!!!!

 

[jjjrmx5]

Do cordless impact drivers prevent cam out on screws the way manual impact drivers (the ones you hit with a hammer) do?

With bolts, does the repeated hammering risk rounding off the bolt?

Not really the same tool meant for the same purpose to me and think this is where the "impact" terminology that the cordless tool world uses gets murky.

You buy any size of the higher end true square drive cordless impact (a'la the $700 Snap-On cordless impact) and you get a tools that's job is to remove mainly big and stubborn fasteners, but they (like the air impacts) can tighten nuts down but usually don;t, but you can knock down the anvil clutch to your desired setting on the cordless.

For those impacts with the 1/4" hex drive, I see the big advantage in driving IN fasteners such as screws or lag bolts into word or anything else and the impact nature helps the drive the screws or bolts in easier than a std. drill driver. They also work for removing small to medium bolts, nuts and screws, but torque values are far less than those square drive cordless impacts I mention above.

As for cam-out, your really need to knock the speed down and do a slow removal, but they do act like a std drill driver , which differs greatly from the hammer hitting screw or nut hand held impacts we all know.

I used a 18v impact (1/4 hex shank) to run screws in when fixing a railing last week, and while it worked great, it did cam out if I was not at the right angle or tried to run things in too fast, same as it would for a drill driver.

While the cordless impacts have some overlap, I would never expect a 1/4" hex impact to pull duty as a heavy duty square drive unit in an auto shop. Different tools for different jobs to me.

 

[stickshift]

I have the makita you are talking about, and it is one of the best tools i own, as a everyday mechanic. I use it for everything inside the car to the engine area. Valve covers, oil pans, trans pans, most covers and air filter boxes. with alot of brakets you have to break it loose, which some will say defeats the purpose, but breaking loose and using it to remove bolts that are long make it well worth it. I have thought about picking up a bigger model but space is usually a issue so they wouldnt help alot. The one thing i highly recomend for it is a large selection of 1/4" dr. swivel sockets. They are a godsend when using that thing!!!!

Do you find that the high frequency, but relatively weak hammering, of a 12v impact driver damages the fasteners? From what I've read, the heavier, but lower frequency, hammering of an impact wrench is less damaging to fasteners.

Do you think the 12v impact allows you to get into places on the car that an 18v impact driver wouldn't?

 

[jjjrmx5]

Do you find that the high frequency, but relatively weak hammering, of a 12v impact driver damages the fasteners? From what I've read, the heavier, but lower frequency, hammering of an impact wrench is less damaging to fasteners.

Do you think the 12v impact allows you to get into places on the car that an 18v impact driver wouldn't?

I can speak from experience of tearing more than 2 new cars and SUV's down a day and then modding them and assembling them that both the 12v and 18v cordless impacts work fine, but both have thier place.

12v's are great for interior bolts an screws on cars when disassembling where 1/4" drive sockets and PH1 and PH2 bits are the norm and can be used with std. bits and 1/4" drive adaptors.

When you get in re-assembly, you have to be careful tho, as drive too hard or get to impact happy and you strip out the nut, t-nut or crack any trim or worse due to torque. 18v and added torque add to the "be careful" factor. The 18v's are also larger, so the warnings are thus doubled as is access to tight places. They require a "feel" and are not just a set-it and forget-it deal.

That leads us to the "stripped fastener" dilemmna, which is really just using the right tool and bit for the job as well as finesse. Too fast or sloppy and you FUBAR your fastener. No different than any other tool or bit.

I love the cordless impacts, but they can cause more harm than good if used incorrectly. much like hard torquing lug nuts with a 1/2 air impact and no hand torque wrench or no torque stick.

 

[Greatbear]

I started out using adapters to fit 1/4 and 3/8" sockets onto my 1/4" hex shank impactors with decent success, but I eventually got a 12V DeWalt 3/8" impact wrench mostly to squeeze into smaller spaces that the other ones (made long because of the adapters) had trouble going. I noticed that the torque delivered to the fastener was noticeably greater despite similar ratings among the tools. I figured the adapters were absorbing some of the impact action torsionally (like a torque stick does) as well as from the added mass. While the manufacturers might be a bit enthusiastic about their ratings, I think it is the less-than-ideal conditions of actual use that reduce the real world numbers. The manufacturers will measure the torque directly from the chuck, but once you place a socket/adapter/driver on it, the real world torque drops. Even going from a 10mm to a 19mm socket drops the torque as the heavier socket absorbs more of the impacting action into its mass.

 

[Outlawmws]

Do cordless impact drivers prevent cam out on screws the way manual impact drivers (the ones you hit with a hammer) do?

With bolts, does the repeated hammering risk rounding off the bolt?

Assuming you are talking about Phillips head screws, if a hammer impact driver is camming out, either the screw has more than just torque holding it in (Locktite) of the tip is not a good fit (essential).

What is it you are camming out on?

 

[stickshift]

Assuming you are talking about Phillips head screws, if a hammer impact driver is camming out, either the screw has more than just torque holding it in (Locktite) of the tip is not a good fit (essential).

What is it you are camming out on?

Just wondering if a cordless impact driver presses in while delivering rotational force the way a hammer impact driver does, or does a cordless impact driver deliver ONLY rotational force?

 

[d33pt]

my $40 18v ryobi impact rated for 800 in lbs breaks loose my lug nuts tightened to 85 ft lbs. i use it with the hex to 1/2" adapter, and it works great with the HF impact sockets.

 

[Outlawmws]

Just wondering if a cordless impact driver presses in while delivering rotational force the way a hammer impact driver does, or does a cordless impact driver deliver ONLY rotational force?

None that I'm aware of do anything except rotate. It takes a hammer impact for that.

 

[stickshift]

None that I'm aware of do anything except rotate. It takes a hammer impact for that.

OK, so powered impact drivers are more like impact wrenches than like hammer impact drivers in how they function.

And the difference between powered impact drivers and impact wrenches is the former are 1/4" hex, while the latter are 3/8" or 1/2" square drive (and tend to be more powerful)?

Man, this terminology is confusing.

 

[Danglerb]

The ones you hit with a hammer, impact drivers, are for single impacts. You hit the back and a internal ramp twists the drive tip at the same time as the blow drives the tip into the fastener reducing cam out.

All of the impact wrenches uses some kind of motor to spin a device that hits the drive anvil once or twice a revolution, and air motor, AC motor, or cordless DC motor, hex drive or square drive they are basically the same differing in power.

The 1/4 hex drive may "look" similar to the square drive, but all I have looked at closer seem to use a lower power mechanism, but I also agree the hex to square adapters seem to **** up a lot of the impact. Haven't tried it yet, but I bought hex drive nut setters to see if they deliver more impact with my 10.8v Bosch PS40 impactor.

Many drivers have a torque limiter of some kind, so for full force make sure its set correctly.

 

[TheGrooveking]

I foudn the Bosch 12V impactor to be less powerful than the Milwaukee M12 12V 3/8" drive impact wrench. I did a side by side comparison and used a 1/2" torque wrench(Armstrong - recently calibrated) and the Bosch could loosen a 1/2-13 bolt tigthtened to 68 ft lbs., but that was holding the trigger for over 50 seconds. The Milwaukee M12 was able to loosen up to 78 ft. lbs. and did so in 21 seconds.

TheGrooveking

 

[rlitman]

I have both Bosch 12V impactors, and the newer one is both significantly more powerful and spins faster. The biggest advantage of the newer version is that it is 1 1/2" shorter.

 

[jjjrmx5]

I have both Bosch 12V impactors, and the newer one is both significantly more powerful and spins faster. The biggest advantage of the newer version is that it is 1 1/2" shorter.

Then you want to tell me the difference between:

Bosch 12v Impactor with 1/4" hex drive:
http://www.amazon.com/dp/B0002VAFUC/?tag=atomicindus08-20

and Bosch 12v Impactor with square drive:
http://www.google.com/products/cata...a=X&ei=9_jUTr_0Eov4sQLhtMWVDw&ved=0CFwQ8wIwAw

And THEN, you have the smaller Bosch 12v Impactor which uses the cylindrical batteries that fit in the handle vs hang off the bottom.
http://www.ohiopowertool.com/p-851-bosch-12v-litheon-impactor-fastening-driver-ps41-2a.aspx

It is a very confusing tool designation and very few can truely tell you what means what in the cordless impact world and the offereings are changing every few months.

 

[rlitman]

The first two were the older generation NiCd. Avoid that. It's old tech.
The third one is Li-ion. These weigh less, and have more power than the NiCd.
The square drive type is what you want, if you're driving sockets a lot, but I don't know of a lithium one of those.

Basically, the hex drive is made to drive screws. I use socket adaptors in mine sometimes, but if it's something I would reach for a 3/8" drive socket, and not use a 1/4" drive on, it's probably beyond what I can expect from that machine.

 

[JASTECH]

Hmm, so I need to ask Santa for M18 and sell my M12 stuff? The reason my Dad helped me and suggested them do to my disability. But I seem to be having issues with the batteries holding their charge. I do keep them in the outbuilding if that makes any difference?