what is a peck-drilling subroutine for a cnc machine
Drilling In computer numerical control (CNC) machine tools a process called peck drilling, or interrupted cut drilling, is used to keep swarf from detrimentally building up when drilling deep holes (approximately when the depth of the hole is three times greater than the drill diameter). Peck drilling involves plunging the drill part way through the workpiece, no more than five times the diameter of the drill, and then retracting it to the surface. This is repeated until the hole is finished. A modified form of this process, called high speed peck drilling or chip breaking, only retracts the drill slightly. This process is faster, but is only used in moderately long holes, otherwise it will overheat the drill bit. It is also used when drilling stringy material to break the chips.[9][10][11]
Socket wrench Socket wrenches are most commonly hexagonal, or more commonly referred to as "6-point" in lay terms. Sockets are driven by being attached to the driving tool via a male/female square connection fitting (called the square drive). Standard sizes of square drives around the world include 1/4", 3/8", 1/2", 3/4", 1", 1-1/2", 2-1/2" and 3-1/2" square drive sizes (a de facto international standard with no metric equivalents[citation needed]) along with some lesser used drivers such as 5/8" square drive, and both #4 and #5 spline drives specified in ANSI B107 specifications. This wide range of square drive sizes provides for a wide variety of socket types and sizes to suit small to very large nuts and bolts. Some square drivers have a through hole to attach the socket to the driver (using a retaining ring with o-ring and pin type, or single piece molded retaining rings), a locking pin, or friction ball. Some common hand ratchets employ a quick release button on their top for quick socket release of smaller sockets.The tool chosen to drive the socket wrench ultimately supplies the mechanical advantage needed by the user to provide the torque needed to loosen or tighten the fastener as may be required. Larger drivers are typically used with higher torque, while smaller drivers are used for convenience in smaller low torque applications. Given the limits of human strength and fatigue, torque above 600Â ft-lbs of torque will generally involve some kind of power assist, instead of the user simply pushing on the handle of a wrench. Very large sockets and drivers are typically powered by hydraulics to achieve torque.