I have the mac one too. ITs a rebadged ingersoll ti impact. Save yourself about $100 and get the IR not the mac one.
It's not the brand name you buy, it's the specific model of impact wrench.
Again, it's not the brand name on the tool, it's the specific tool model that's important.
Looking through the newest MAC catalog that I have, it appears that MAC is soucing from Ingersol-Rand and
from AirCat, among others. Probably Florida Pneumatic, too; but I can't tell for sure.
All I know is that after reading this thread, I went out on the internet and started looking at specs for modern impact wrenches...and now I'm likely to upgrade from "Old Reliable". I expect my IM510B will be for sale soon.
There's still a huge amount of low-powered JUNK available, even from the "big names". But the cream of the crop in 3/8 drive is about as powerful as an ordinary 1/2" drive; and the cream of the 1/2 drive is as good as cheap 3/4 drive stuff--which I never thought I'd see.
Of course, a top-line 1/2" drive unit costs more than a bottom-feeder 3/4" unit; but weighs less and is less bulky.
A GOOD air compressor helps too. At 90 lbs. air pressure not much moves but at 125 things happen
Most air impacts are rated with 90 psi AT THE INLET OF THE TOOL, with the tool RUNNING. 90 psi in the tank gets you about 70 psi at the tool when the trigger is pulled.
Yeah, more pressure in the tank is a wonderful thing.
At least one company is starting to rate the power of the impact tool using 125 psi at the tool inlet instead of "industry standard" 90 psi. I kinda think that's cheating, since most home shops won't be able to deliver that much air pressure.