Several years ago I picked up the English (Brownell's) dent raisers in 12 and 20 gauges from an estate. I knew the previous meticulous owner and the original instructions were in each set.
Being relatively inexperienced and not knowing enough to "know better", I read the instructions prior to use, then I read them again. I asked myself how I could screw this job up (as I ALWAYS do), and the only way I could envision was to go at it too aggressively and push out the dent(s) to the point where I would create a bulge. I went at it "slow and easy" per the instructions and all went well. Good job.
Have since done several more similar jobs, and have pushed out the dents just fine - no problemo.
