Lathe Chuck Key
The other thread is perfect - has sent me looking for 'square key steel' and I found a hardened steel tool quality lathe key - have used a bench grinder and ground it slight flatter at end to flatten end chamfer and it has just removed freehub when in a metal vice - perfect!
Lathe Chuck Key Imperial and Metric Variation Square Head Engineering Variation...7/16
see ebay
£8.49!