Chip-Packing

Why Power Consumption Tracks Wear As a gun drill wears, the cutting edge dulls. A dull edge requires more force to shear the material, and the spindle motor draws more power to maintain the programmed RPM. The power increase is proportional to the edge wear. I have verified this relationship by measuring power consumption against measured edge wear across dozens of tools. The correlation is consistent enough that I trust the power reading as a wear indicator without stopping the machine to inspect the edge. ...

I have drilled more titanium deep holes than I care to count, and I learned the hard way that titanium is not “tough steel.” It is a different animal. The thermal conductivity is roughly one-fifth that of steel. The chips are not chips – they are razor-edged bands that carry all the heat out of the cut. The work-hardening rate is aggressive enough to ruin a new gun-drill in seconds if you let the tool rub instead of cut. Every fix I learned on steel had to be re-learned for titanium. This article covers the specific failure modes I encounter in titanium deep hole drilling and the adjustments that actually work. ...