Fireworks shell cut in half.
https://s3-us-west-1.amazonaws.com/h...f_fullsize.jpg
Previously:
https://www.homemadetools.net/forum/...811#post152357
https://www.homemadetools.net/forum/...933#post206904
https://www.homemadetools.net/forum/...818#post206539
https://www.homemadetools.net/forum/...562#post201163
https://www.homemadetools.net/forum/...462#post142793