molle pronounced / ˈ m ɒ l. l iː /, similar in pronunciation to the name molly is an acronym for modular lightweight load-carrying equipment.it is used to define the current generation of load-bearing equipment and backpacks used by a number of nato armed forces, especially the british army and the united states army.. the system's modularity is derived from the use of pouch attachment .
the phrase speeds and feeds or feeds and speeds refers to two separate velocities in machine tool practice, cutting speed and feed rate.they are often considered as a pair because of their combined effect on the cutting process. each, however, can also be considered and analyzed in its own right.
engineering ding abbreviations and symbols are used to communicate and detail the characteristics of an engineering ding.this list includes abbreviations common to the vocabulary of people who work with engineering dings in the manufacture and inspection of parts and assemblies.
a set screw or grub screw is a type of screw generally used to secure an object within or against another object, normally without using a nut see bolts compared with screws .the most common examples are securing a pulley or gear to a shaft.set screws are usually headless also called blind , meaning that the screw is fully threaded and has no head projecting past the major diameter of the .
hobbing is a machining process for gear cutting, cutting splines, and cutting sprockets on a hobbing machine, which is a special type of milling machine. the teeth or splines of the gear are progressively cut into the material a flat, cylindrical piece of metal by a series of cuts made by a cutting tool called a hob.
blanking and piercing are shearing processes in which a punch and die are used to modify webs.the tooling and processes are the same between the two, only the terminology is different: in blanking the punched out piece is used and called a blank; in piercing the punched out piece is scrap. the process for parts manufactured simultaneously with both techniques is often termed 'pierce and blank.'
a leading-edge slot is a fixed aerodynamic feature of the wing of some aircraft to reduce the stall speed and promote good low-speed handling qualities. a leading-edge slot is a spanwise gap in each wing, allowing air to flow from below the wing to its upper surface. in this manner they allow flight at higher angles of attack and thus reduce the stall speed.
cutting a single helical groove into a screw-stock cylinder yields what is referred to as a single-thread screw. similarly, one may construct a double-thread screw provided that the helix angle is the same, and a second thread is cut in the space between the grooves of the first.
in milling the spindle is where a cutting tool is mounted. in some situations material must be cut from a direction where the feature can not be seen from the perspective of the spindle and requires special tooling to reach behind the visible material.
jousting is a martial game or hastilude between two horsemen wielding lances with blunted tips, often as part of a tournament.the primary aim was to replicate a clash of heavy cavalry, with each participant trying hard to strike the opponent while riding towards him at high speed, breaking the lance on the opponent's shield or jousting armour if possible, or unhorsing him.
shaping or slotting is largely used for cutting keyways that do not extend through the full length of the part. like keyseating, shaping uses a single-point cutting tool for cutting, however, shapers are not guided through the cut on a fixed post. as such, shaper cuts are generally more susceptible to deflection than keyseater cuts. milling
notching is a metal-cutting process used on sheet-metal or thin bar-stock, sometimes on angle sections or tube. a shearing or punching process is used in a press, so as to cut vertically down and perpendicular to the surface, working from the edge of a work-piece. sometimes the goal is merely the notch itself,.
the workpiece is held in the indexing head in the same manner as a metalworking lathe. this is most commonly a chuck but can include a collet fitted directly into the spindle on the indexing head, faceplate, or between centers. if the part is long then it may be supported with the help of an accompanying tailstock .
the geneva drive or maltese cross is a gear mechanism that translates a continuous rotation movement into intermittent rotary motion.. the rotating drive wheel is usually equipped with a pin that reaches into a slot located in the other wheel driven wheel that advances it by one step at a time. the drive wheel also has an elevated circular blocking disc that 'locks' the rotating driven wheel .
the gear cutter is mounted on the spindle, and the gear blank is mounted on the arbor. the cutter reciprocates up and down while the workpiece is gradually fed into the cutter. at the end of each cutting rotation, the spindle is retracted slightly to discourage any more cutting into the new cut teeth of the gear. references. todd, r 1994 .
a planer is a type of metalworking machine tool that uses linear relative motion between the workpiece and a single-point cutting tool to cut the work piece. a planer is similar to a shaper, but larger, and with workpiece moving, whereas in a shaper the cutting tool moves.
slot broaches g & h are for cutting slots of various dimensions at high production rates. slot broaching is much quicker than milling when more than one slot needs to be machined, because multiple broaches can be run through the part at the same time on the same broaching machine.