Recent Blogs
Fiddle Drill: Bow Travel and Alternating Rotation Calculator | FIRGELLI
Calculate turns per one-way bow stroke and average rotational travel from contact diameter, bow travel and stroke rate. Includes an alternating-motion animation.
Spiral Push Drill: Lead and Stroke Geometry
How a Persian drill converts push force into reciprocating rotation through a quick-thread spindle. Used in jewellery, watchmaking, and dental tool design.
Pump Drill Stock: Declared Cord-Travel Ledger
Pump Drill Stock explained — how the reciprocating drill stock converts vertical pumping into rotary drilling for jewellers, lapidaries and bow-drill workshops.