I need to drill a hole of a few mm through a piece of hardened steel being around 5mm thick. The workpiece is mounted on a wall, so I do not have the option of putting it under a stationary column drill.
Searching the internet left me with the following advice: use a extra hard drill bit, such as a Cobalt enhanced steel bit, a cooling liquid (e.g. some oil) and drill with not too high rpm.
Well, I tried this, and my experience was the following:
- I used Cobalt drill bits, but with no effect.
- Drill bit had quite some tendency to travel, but I managed to keep it steady focused on one point for minutes, but this didn't even scratch the surface.
- I have the feeling that the reason the drilling didn't work, was that you need to have a very small hole or dimple to give the drill something to start on, and that is the problem: how do I make this little start 'pit'? Hardened steel seems totally unpenetrable.
Am I doing something wrong here? All tips are welcome.
Thanks and regards.
Searching the internet left me with the following advice: use a extra hard drill bit, such as a Cobalt enhanced steel bit, a cooling liquid (e.g. some oil) and drill with not too high rpm.
Well, I tried this, and my experience was the following:
- I used Cobalt drill bits, but with no effect.
- Drill bit had quite some tendency to travel, but I managed to keep it steady focused on one point for minutes, but this didn't even scratch the surface.
- I have the feeling that the reason the drilling didn't work, was that you need to have a very small hole or dimple to give the drill something to start on, and that is the problem: how do I make this little start 'pit'? Hardened steel seems totally unpenetrable.
Am I doing something wrong here? All tips are welcome.
Thanks and regards.