All in all I am very satisfied with the Keil HSS drills. Cut very well in the steel (also with cordless drills) and looked quite beautiful in delivering sharp .. For home use, really very good when it comes time drill out screws, etc. Today they had to serve to rödeln through thicker steel ... the right steel is unknown, but it went through 25mm (car repair bench). Centrepunch I'd despite the advertised Split-Point cut already recommended unless there is a little more cramped and not perfectly straight seated. With it forward and lower speed the drill came well through the steel. Significantly easier than with the larger KWB HSS drills which were used thereafter. However, was drilled with oil and more Softly, so that the drill does not tilt and break. Was pre-drilled with 6 or 7 mm and then drilled with 10mm. Then continue normal KWB HSS drills was reamed to 16mm. The whole thing ran at me from any problems. My brother has been caught and drilled the 7.5mm drill. In short ... no Grobmotoriker. When the drill jumps because it sits at an angle in the borehole and tries to correct the whole thing with more speed you get the drill also some quirks from. At the cutting edge a few corners have erupted. Note: moderate pressure and just cause, then there are no problems. The drills which I have used are no major signs of wear. See the KWB drill because now something worse for wear ... only gripe: The retaining holes in the cassette for drills are a little too precisely manufactured. When the drill has even jammed briefly in the chuck and pulled a ridge is no longer one gets the in its holder inside the box. Otherwise, the box is good.
So if you can, please use a little caution and not primarily to counteract violence. Then they also do not break as quickly. Hart is now times unfortunately also brittle. For occasional drills normal HSS should be sufficient and is then not quite as vulnerable as the solemnities stories. If you often times high strength bolts (eg 8.8er) or so I can ausbohrt the HSS-Co already rather recommend.
