Holes that qualify as âdeep-hole drilling are three or more drill bit diameters. deep. When drilling this deep, the speed and feed rate must be adjusted to. reduce friction. Friction creates heat, and heat build-up in the drill bit can cause. failure and breakage. Lubricants help dissipate heat from the tip of the drill bit, prolonging drill life, and should always be used when deep-hole drilling.
Humphry's Peak (not to be confused with Mt Humphrey's in the Sierra) in the Coconino National Forest, is the tallest summit in all of Arizona. It is part of the San Francisco Peaks, a volcanic mountain range 9 miles north of Flagstaff, Arizona.
Mount Washington (New Hampshire) Mount Washington, called Agiocochook by some Native American tribes, is the highest peak in the Northeastern United States at 6,288.2 ft (1,916.6 m) and the most prominent mountain east of the Mississippi River. The mountain is notorious for its erratic weather.