Originally Posted by
3alarmer
...not certain you've used an impact wrench in a circumstance like this. It's not like going at a lug nut on a car wheel, and the bicycle itself tends to move around easily. So the business end of the tool either slips out or can damage the little teeth in the BB fitting (they are either aluminum or plastic.) So it might work, but you're way better off
bolting the tool to the sealed unit spindle with a properly sized bolt and some fender washers, putting either an adjustable or (better) properly sized box end wrench on the tool, and hitting the wrench with a mallet or hammer. Plus you get to use a hammer.
The tool was bolted in. Fortunately the cup was Al. Worst one I ever had. It was the guys winter bike and never saw any maintenance. The spindle was already out as the bearings were literally gone so I had to McGuyver bolting the tool in. Also used plenty of Kroil over a week and the propane torch. I didn't really want to run an air hose through the house and into the basement for the impact. I had a bit more control with the breaker bar and pipe. As it was the BB threads in the Al shell needed some chasing afterward and I told him it was probably the last BB that would get installed in that frame.