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.
A common misperception is that this peak is the highest in Arizona because you unable to see Humphry's Peak behind it from Flagstaff, Arizona. It's summit is 12,356 feet above sea level. The mountain is closed to climbers in winter due to snow and protecting the fragile tundra enviroment.
Distance from Phoenix: 144 miles north; two-hour drive. Why it made our list: Flagstaff is home to Humphreys Peak, the highest point in AZ and one of the few places to ski or snowboard in the state. Yes, it snows in Arizona. The High Country gets about 110-inches of the white stuff each year.