Overview:

I was tired of having to remove six screws from my trimmer's mount every time I wanted to narrow the opening for the small drill bit or vice versa, so I designed this system. It consists of a ring that is screwed into the trimmer's mount and interchangeable inserts of various diameters, which can be rotated and pulled out for replacement.

I've also designed some wrenches that make it easier to rotate the inserts, and then you can use the wrenches to eject them.

I've included my Fusion 360 design, so you can use the provided parameters to create your own customized inserts.

Print:

These parts can be printed using materials such as PLA, PETG, and ASA. If you print them in the direction shown, you won't need to use support structures. For added strength, make sure to print the wrench as shown in the diagram.