A real pig of a bottom bracket this week. Either the non-drive side cup was incorrectly threaded, or a drive-side cup was used by mistake. The end result was the same, a worn bottom bracket with a non-drive side cup that refused to be removed. As you can see, a little bit of Heath-Robinson goes a long way, and the offending item finally came free. This left a very sorry, and extremely chewed bottom bracket shell. The Park Tool tapping and facing tool made light work of it though, allowing a new Shimano-MTB square tapered bottom bracket to be fitted. The right tool for the job.