18v impact wrench vs 240v impact wrench

[Garybee]

I've decided that I could do with an impact wrench for dealing with suspension bolts, crank pulleys etc. when there isn't room for a breaker bar. Although I'd prefer pneumatic I don't believe there's any point unless you 'go large' with the compressor, lines and fittings which has left me looking at mains or cordless.

Looking at the Dewalt 1/2" drive tools, their cordless tools clain to deliver around double the torque of their 240v kit. Is this feasible? If it was just marketing waffle I would expect the same to be applied to their entire range. I know Lithium batteries are capable of discharging very quickly but are they really better than 13 amp mains?

[Garybee]

arginite said:

I have the DCF899 and can't complain it's opened everything I have thrown at it since getting it at Christmas.

That's the one I was thinking of and it seems pretty well priced too. What's toughest thing you've used it on so far?

For interest spec's of the two options below:-

240v mains (DEWALT DW292-GB):-

Max Torque: 440 Nm
Power Input: 710 Watts
Power Output: 370 Watts
No Load Speed: 2200 RPM
Impacts per Minute: 2700 IPM
Max. Bolt Diameter: M20
Bit Holder: 1/2in
Length: 292 mm
Height: 216 mm
Weight: 3.2 kg
Sound Pressure: 84dB (A)

18v cordless (DeWalt DCF899HN):-

Bit Holder: 1/2in Hog Ring.
No Load Speed: 0-400/0-1,200/0-1,900/min.
Impacts Rate: 0-2,400/bpm.
Max. Torque: 950Nm.
Breakaway Torque: 1625Nm.
Max. Bolt Diameter: M20.
Length: 224mm.
Height: 225mm.
Weight: 2.62kg.


I'm just a bit dubious of the cordless being better in reality.

[Garybee]

PositronicRay said:

The thing that puts me off cordless stuff is it's always flat when I want it!! Okay if you're using it all the time and remember to put on charge, occasional use a nono.

Yep, I know exactly where you're coming from there. In this case I think it will be ok but only because I have quite a few Dewalt XR 18v tools so there'll always be at least a couple of charged batteries around. The stuff seems quite good despite being the Stella of the tool world (their marketing department has everyone convinced that it's really expensive so when people see it available fairly cheaply it seems like good value).