Ikea Blanda cycle bell

Ikea Blanda is a good bycle bell.
Make a 3mm hole in the center , assemble and enjoy its sound.
It is made for 22 mm diameter tube.
Inventor files are included

27/08/2013 Added a tool for drilling the bell in the center.

28/08/2013 Revised tool

30/08/2013 Revised the upper part. Added 2 mm on top to make it easier sound.