Do not confuse removal depth with drill-tip depthBackdrill depth is measured from a specified entry face. This conceptual drawing separates full-diameter removal from the drill tip and the protected connection; it is not a production depth prescription.Do not confuse removal depth with drill-tip depthSectional explanation · Copper barrel below the cut remainsL1L2L3L4L5L6L7L8Entry face: depth zeroFull-diameter removal depthAdditional tip advanceProtected connection depthUse one entry-side datum. Intermediate copper clearances are omitted in this sketch.³Ô¹Ïtv · Engineering illustration · Conceptual, not to scale