wbrian63
Well-known member
In a separate thread, I posted some questions about the Milwaukee 18v Lithium Ion impact driver I just got, as I'm not happy with the performance of the tool.
Here, I'll ask some opinions as to what the different specs of my 3 impact drivers really mean in terms of potential performance.
3 different impact drivers:
Dewalt 14.4v, model, (I think) DC820.
0-2400 no-load rpm
0-2700 ipm (impacts/minute)
1,240 inch #'s torque
Ridgid 18v, model R82320
0-2850 no-load rpm
0-2800 ipm
1,400 inch #'s torque
Milwaukee 18v, model 2650-20.
0-2200 rpm
0-3200 ipm
1,400 inch #'s torque.
The Dewalt is oldest, the Milwaukee is brand new.
Comparing the capabilities of each of the tools, the Dewalt comes out on top. Even though its #'s are lower than the Ridgid, it out-performs. I suspect the higher rpm # for the Ridgid is it's downfall here. Higher rpm's require more amps, which equals a faster drain on the battery.
This new Milwaukee takes 100-125% longer to drive screws than either of the other tools.
So here's what I'm wondering, and need to determine (if possible) - do the design specs indicate the Milwaukee will always be slower at driving screws than the other drivers?
It's 200 rpm slower than the Dewalt, and 650 rpm slower than the Ridgid. However, the ipm's for the Milwaukee best Ridgid by 400 and Dewalt by 500. I'm thinking that it's not just the ipm's that matter, but the weight behind the ipms.
If the # of impacts were the sole determining factor, then I think it would mean I could drive a railroad spike with a tack hammer faster than a sledge hammer, simply by hitting the spike faster, right?
The for impact drivers, the torque #'s are a combination of 3 factors - how fast the chuck is spinning, how heavy the impact weights are and how often they hit the anvil (ipm).
I'm suspecting that the Milwaukee's far higher impact count is as a result of either a lower spring tension in the impact mechanism, or a lighter impact pawl weight, or both. Either way, the results are going to be lower than the other two tools, in my opinion.
However, the torque #'s should provide an even way of evaluating the ability of each tool to drive a screw.
Just looking at torque vs rpm, the Milwaukee is equal to Ridgid in torque, but will drive a fastener 84% as fast (2200 rpm vs 2850). Same comparison vs Dewalt is a closer match (92%). These #'s do not equate to my real-world experiences, thus far.
Even a 16% difference would be easily eliminated if the Ridgid were driving a screw through a lot of heart wood, while the Milwaukee was driving in sap wood...
The rub for me, and for everyone, is that as consumers, we should be able to look at the specs for any given tool and KNOW how it will work in the real world, as compared to its brethren, all other things being equal. I shouldn't have to spend hundreds of dollars to find out that while the tool may be properly constructed, its design specifications will not meet my requirements, even though the published #'s state that it should...
What I'm concluding at this point is that there is something wrong with the Milwaukee. In the real world, if the torque #'s are accurate, it will be slower than either the Dewalt or the Ridgid, but not more than twice as slow.
I'd appreciate other opinions on this.
Thanks!
Here, I'll ask some opinions as to what the different specs of my 3 impact drivers really mean in terms of potential performance.
3 different impact drivers:
Dewalt 14.4v, model, (I think) DC820.
0-2400 no-load rpm
0-2700 ipm (impacts/minute)
1,240 inch #'s torque
Ridgid 18v, model R82320
0-2850 no-load rpm
0-2800 ipm
1,400 inch #'s torque
Milwaukee 18v, model 2650-20.
0-2200 rpm
0-3200 ipm
1,400 inch #'s torque.
The Dewalt is oldest, the Milwaukee is brand new.
Comparing the capabilities of each of the tools, the Dewalt comes out on top. Even though its #'s are lower than the Ridgid, it out-performs. I suspect the higher rpm # for the Ridgid is it's downfall here. Higher rpm's require more amps, which equals a faster drain on the battery.
This new Milwaukee takes 100-125% longer to drive screws than either of the other tools.
So here's what I'm wondering, and need to determine (if possible) - do the design specs indicate the Milwaukee will always be slower at driving screws than the other drivers?
It's 200 rpm slower than the Dewalt, and 650 rpm slower than the Ridgid. However, the ipm's for the Milwaukee best Ridgid by 400 and Dewalt by 500. I'm thinking that it's not just the ipm's that matter, but the weight behind the ipms.
If the # of impacts were the sole determining factor, then I think it would mean I could drive a railroad spike with a tack hammer faster than a sledge hammer, simply by hitting the spike faster, right?
The for impact drivers, the torque #'s are a combination of 3 factors - how fast the chuck is spinning, how heavy the impact weights are and how often they hit the anvil (ipm).
I'm suspecting that the Milwaukee's far higher impact count is as a result of either a lower spring tension in the impact mechanism, or a lighter impact pawl weight, or both. Either way, the results are going to be lower than the other two tools, in my opinion.
However, the torque #'s should provide an even way of evaluating the ability of each tool to drive a screw.
Just looking at torque vs rpm, the Milwaukee is equal to Ridgid in torque, but will drive a fastener 84% as fast (2200 rpm vs 2850). Same comparison vs Dewalt is a closer match (92%). These #'s do not equate to my real-world experiences, thus far.
Even a 16% difference would be easily eliminated if the Ridgid were driving a screw through a lot of heart wood, while the Milwaukee was driving in sap wood...
The rub for me, and for everyone, is that as consumers, we should be able to look at the specs for any given tool and KNOW how it will work in the real world, as compared to its brethren, all other things being equal. I shouldn't have to spend hundreds of dollars to find out that while the tool may be properly constructed, its design specifications will not meet my requirements, even though the published #'s state that it should...
What I'm concluding at this point is that there is something wrong with the Milwaukee. In the real world, if the torque #'s are accurate, it will be slower than either the Dewalt or the Ridgid, but not more than twice as slow.
I'd appreciate other opinions on this.
Thanks!