Small-Diameter Gundrills Offer Speed, Precision

Tungaloy has expanded its DeepTriDrill line of inserted indexable gundrills to include diameters ranging from 14 to 15.9 mm.

The brazed gundrill and solid twist drill are common tools for challenging, bottleneck-inducing deep-hole drilling operations. According to the company, the typical brazed gundrill has a single-point, uncoated carbide tip, which doesn’t allow for high parameter drilling. A solid twist drill is better for high-feed drilling, but curved holes and chip clogging are common setbacks. As an alternative, the DeepTriDrill features one insert and two guide pads oriented in an optimized position on the drill head. According to the company, the result is tight-tolerance drilling to high circularity and straightness with surface finish quality that’s traditionally reserved for brazed gundrills.

The insert incorporates chipsplitters on the chipbreaker geometry to break chips into smaller pieces. Improved chip evacuation and reduced cutting forces enable higher feed rates than traditional gundrills, the company says. It adds that the coated insert and guide pads also enable the tool to reach higher cutting speeds.