A neighbor had to fix a curtain support, making a sort of mortise into a piece of pipe.
The support was basically a pipe made with some mystery metal looking like heavily compressed aluminum dust.
At the first attempt to make a hole with a self-proclaimed HSS Chinese bit, 500 RPM and very light feeding, I got as a result just a notch and a bit 1 cm shorter.
A brand new Bosch HSS bit completed the hole, with the help of some cooking oil (all I had in that moment!), and even the Bosch bit became almost dull. Around the hole instead of chips there was a sort of crust, like slag, pretty hard to be filed.
Then I had to make two cuts with an HSS slitting saw 0.6 mm thick.
After a test I decided there was the need of something constantly dripping oil on the blade to get a decent result, so I filled an empty tube of cold pills with oil, attached to it an IV line (some time ago the drugstore had to dump a full box of them because they were expired, and I kept them to water the plant pots) running just near the chuck and I named it "coolant hose". Of course I removed the needle…
Here is the "IV drill press":
I used an M6 thread bar to push the vise under the saw, turning it at 1 RPM: an astounding advance speed of 1 mm/minute.
The mortise anyway is perfect, the saw blade is not yet dull and the neighbor is happy.