Why not offer the customer to make and engrave a nice plaque (of a metal that is nice to cut and to finish) and srew or glue it onto the shaft? This would even look better than the engraving on the axe itself, and would make the whole piece look more interesting.
You very well deserved this honor, Sam! For sure you did an excellent and very professional job. I know what a huge challenge and as well great delight is to teach the Grandmasters at GRS, even for a well versed instructor or teacher. I have vivid and great memories of 2009...
It´s called burnishing and widely used in the US. Here you can read about these common techniques: http://www.antaresinc.net/FactBRN.html
There was some flex in the machine, play in the spindle or/and the engraver did not guide the stencil well enough. Thus the character looks so wobbly...
I remember that was feeling a bit lonesome during my first few solos... but what a rewarding achievement and pleasure! Great activity, - just demanding enough for you.
I hope you enjoy it as much as I do (without engine)!
Safe flights and happy landings!
Here is how a similar design can look like, if it is CNC-engraved properly. This was student work done in really tough, inoxidable steel. The handle is about 5mm thick, engraving depth 1mm. Hand work: Filing and polishing of the blade, surface line engraving and matting of the backgrounds.