Carbide insert coarse turned surface (still left at chuck end): with short curly swarf, no smearing/ hogging at any speed/ feed. Finishing cut (right to left) with HSS shear tool: Incredible shine, foil-thin wisps of swarf (below), make me accept the evenly dispersed minute gas pores. Cuts even better than commercial grade free-cutting Al rod (at £ 25/kg). This particular (10-12 % silicon) alloy has also the very nice property of cold-ageing / hardening in 30 days. "Not bad" for half a dumped office chair 5-wheel footstand, 1 quid in charcoal and 20 minutes of work!