Making a Face Grooving or Trepanning Tool for the Lathe - it failed!

A friend asked me, if I could make a part for him with a very delicate feature: a groove in its front face. For doing this operation you need to have a special face grooving tool which I didn't have. So I decided to build my own one. The 3D Cad model helped a lot finding the right design for the tool. As I already had a normal parting tool and some parting inserts flying around, I wanted to use these on the face grooving tool as well. It was quite fiddly to get the insert seat in the tool right as some very small features are needed, but I managed to get it right somehow. This could be a great story, if the tool didn't collapse during the first test runs in aluminium. The blade is so thin and the toolsteel I used obviously not strong enought, that the tool completely bend out of shape. A really frustrating experience after so much hours of work that went into this toolbuild. Perhaps someday I will give it a second try with some design improvements and some other material for improved rigidity. I hope you enjoy the build process. Let me know what you think about the design in the comments and feel free to ask and give me some feedback. Thanks for watching my videos. Subscribe to the channel for more mechanical and machining content. My Patreon page: www.patreon.com/wecandothatbetter 00:00 Intro 01:19 Bringing the tool roughly into shape 04:23 Shaping the tool blade on the lathe 09:16 Milling the insert seat 11:31 Finishing the tool on the milling machine 14:19 Final finishing touches and assembly 15:29 First test cuts 16:36 Bad ending