The tooling cost for machining is determined by the total number of cutting tools required and the unit price for each tool. The quantity of tools depends upon the number of unique tools required by the various operations to be performed and the amount of wear that each of those tools experience.
If the tool wear exceeds the lifetime of a tool, then a replacement tool must be purchased. The lifetime of a tool is dependant upon the tool material, cutting parameters such as cutting speed , and the total cut time. The unit price of a tool is affected by the tool type, size, and material. Login Register for free!
Contents 1. Capabilities 2. Process Cycle 3. Equipment 4. Tooling 5. Materials 6. Possible Defects 7. Design Rules 8. Cost Drivers. Max wall thickness : 0. Disclaimer: All process specifications reflect the approximate range of a process's capabilities and should be viewed only as a guide. Actual capabilities are dependent upon the manufacturer, equipment, material, and part requirements.
The load time can depend on the size, weight, and complexity of the workpiece , as well as the type of fixture. Cut time - The time required for the cutter to make all the necessary cuts in the workpiece for each operation. The cut time for any given operation is calculated by dividing the total cut length for that operation by the feed rate , which is the speed of the cutter relative to the workpiece. Idle time - Also referred to as non-productive time, this is the time required for any tasks that occur during the process cycle that do not engage the workpiece and therefore remove material.
This idle time includes the tool approaching and retracting from the workpiece, tool movements between features, adjusting machine settings, and changing tools. Tool replacement time - The time required to replace a tool that has exceeded its lifetime and therefore become to worn to cut effectively. This time is typically not performed in every cycle, but rather only after the lifetime of the tool has been reached. In determining the cycle time, the tool replacement time is adjusted for the production of a single part by multiplying by the frequency of a tool replacement, which is the cut time divided by the tool lifetime.
Cutting feed - The distance that the cutting tool or workpiece advances during one revolution of the spindle and tool, measured in inches per revolution IPR.
In some operations the tool feeds into the workpiece and in others the workpiece feeds into the tool. For a multi-point tool, the cutting feed is also equal to the feed per tooth, measured in inches per tooth IPT , multiplied by the number of teeth on the cutting tool.
Cutting speed - The speed of the workpiece surface relative to the edge of the cutting tool during a cut, measured in surface feet per minute SFM. Spindle speed - The rotational speed of the spindle and tool in revolutions per minute RPM. The spindle speed is equal to the cutting speed divided by the circumference of the tool.
Feed rate - The speed of the cutting tool's movement relative to the workpiece as the tool makes a cut. Axial depth of cut - The depth of the tool along its axis in the workpiece as it makes a cut. A large axial depth of cut will require a low feed rate, or else it will result in a high load on the tool and reduce the tool life. Therefore, a feature is typically machined in several passes as the tool moves to the specified axial depth of cut for each pass.
Radial depth of cut - The depth of the tool along its radius in the workpiece as it makes a cut. If the radial depth of cut is less than the tool radius, the tool is only partially engaged and is making a peripheral cut. If the radial depth of cut is equal to the tool diameter, the cutting tool is fully engaged and is making a slot cut. A large radial depth of cut will require a low feed rate, or else it will result in a high load on the tool and reduce the tool life.
Therefore, a feature is often machined in several steps as the tool moves over the step-over distance , and makes another cut at the radial depth of cut. Peripheral cut Slot cut. These components include the following: Base and column - The base of a milling machine is simply the platform that sits on the ground and supports the machine. A large column is attached to the base and connects to the other components. Table - The workpiece that will be milled is mounted onto a platform called the table, which typically has "T" shaped slots along its surface.
The workpiece may be secured in a fixture called a vise, which is secured into the T-slots, or the workpiece can be clamped directly into these slots. The table provides the horizontal motion of the workpiece in the X-direction by sliding along a platform beneath it, called the saddle. Saddle - The saddle is the platform that supports the table and allows its longitudinal motion. How do you specify milling machine? When was the milling machine invented? Eli Whitney milling machine? What is the difference brtween vertical milling machine and horizontal milling machine?
Function of milling machine? How much does the average milling machine cost? Analysis of forces on horizontal milling machine? When was Cincinnati Milling Machine Company created? What are the differences between lathe machine and milling machine? What are types of milling machines? What is up milling? How a milling machine is used? If you can Justify the choice of using the horizontal milling machine instead vertical milling machinefor making the baseplate? Why we don't use milling machine as driiling machine?
History of milling machine? Problem in cnc milling machine? What are the advantages of milling machine?
Difference between up and down milling machine? What is W-axis on a milling machine? What is the objective of a milling machine? BEd ,. Can we do milling on radial drilling machine? Where was the milling machine invented? Study Guides. Trending Questions. This results in the generation of heat that is used to create a weld between two workpieces, hence the Blast furnaces were first introduced in China around the 1st century AD.
They were further introduced in European countries like Durstel, Germany, Lappyhttan in the 13th century. Due to an Skip to content. Page Contents. Milling machine cutter and workpiece position. Column and knee type milling machine: diagram. Verticle milling machine Source: IndiaMart. Horizontal milling machine Source: IndiaMart. Universal milling machine Source: IndiaMart. Fixed bed milling machine Source: IndiaMart. Simplex milling machine Source: IndiaMart.
Duplex milling machine Source: IndiaMart. Triplex milling machine Source: IndiaMart. Special milling machine. Tracer milling machine. Plain milling operation diagram. Face milling operation diagram. Diagram of End milling operation. Form milling operation diagram. A pantograph is a mechanism that is generally constructed of four bars or links which are connected in the form of a parallelogram. Pantograph machines are available in two dimensional and three-dimensional models. The two-dimensional pantograph is used for engraving letters or other designs.
Whereas three-dimensional models are employed for copying any shape and contour of the workpiece. A profiling machine duplicated the full size of the template attached to the machine. Here the spindle can be adjusted vertically and the cutter horizontally across the table.
A hardened guide pin regulates the movement of the cutter. The longitudinal movement of the table and the crosswise movement of the cutter head follows the movement of the guide pin on the template. The tracer controlled milling machine reproduces irregular or complex shapes of dies, moulds by synchronized matched movements of the cutter and tracing elements.
The movement of the stylus energized an oil relay system which in turn operates the main hydraulic system for the table. This arrangement is termed as a servomechanism. A milling machine is a machine tool that cuts metal as the workpiece is fed against a rotating multipoint cutter. The milling cutter rotates at a very high speed because of the multiple cutting edges, it cuts the metal at a very fast rate.
This machine can also hold single or multiple cutters at the same time. A solid cutter has teeth with the cutter body. The cutters are of smaller diameter and made of one piece material usually of HSS high-speed steel. A tipped solid cutter is similar to a solid cutter, except that the cutter teeth are made of cemented carbide or stellite tips which are brazed on the tool shanks of an ordinary tool steel cutter body to lower the cost of the cutter.
In large milling cutters, the teeth or blades are inserted or secured in a body of less expensive materials. The blades are held in the cutter body by mechanical means. This arrangement reduces the cost of the cutter and enables economy in maintenance, as a single tooth if broken can be readily replaced. In this category of milling cutters, a relief to the cutting edges is provided by grinding a narrow land at the back of the cutting edges.
The profile relieved cutters generate flat, curved or irregular surfaces. Form relived cutter also known as surface milling. These cutters have curved relief provided at the backside of the cutting edges.
These cutters are sharpened by grinding the faces of the teeth. The form relieved cutters are used for generating formed or contoured surfaces. The arbor type cutters are provided with a central hole having a keyway for mounting them directly on the milling machine arbor. Milling cutters having tapered or threaded holes are also available. They are mounted on arbors of different designs. The shank type cutters are provided with straight or tapered shank integral with cutter body.
The straight or tapered shanks are inserted into the spindle nose and are fixed to it by a draw bolt. The facing type cutters are either bolted or attached directly to the spindle nose, or secured on the face of a short arbor called stub arbor. The facing type cutters are mainly used to produce flat surfaces. A milling cutter is designated as a right-hand cutter which rotates in an anticlockwise direction when viewed from the end of the spindle.
A milling cutter is designated as a left-hand cutter which rotates in a clockwise direction when viewed from the end of the spindle. The parallel or straight teeth cutters have their straight or parallel to the axis of rotation of the cutter. The helix angle of parallel teeth cutters is equal to zero. These cutters have their teeth cut at an angle to the axis of rotation of the cutter. The cutters may be distinguished by viewing it from one of its end faces when the helical groove or flute will be found to lead from left to right-hand direction of the cutter body.
The cutter may be distinguished by viewing it from one of its end faces when the helical groove or flute will be found to lead from right to left-hand direction of the cutter body. These cutters are a conventional type of milling cutters whose dimensions such as cutter diameter and width, the diameter of the centre hole, width and depth of keyways, etc.
Special milling cutters are designed to perform special operations which may be the combination of several standard operations. The cutters may have standard or non-standard dimensions. This types of milling cutters are circular in shape and have teeth on the circumferential surface only. The cutters are intended for the production of the flat surface parallel to the axis of rotation of the spindle.
The plain milling cutter teeth may be helical or straight according to the size of the cutter. The figure shows a straight teeth plain milling cutter. Very wide plain milling cutters are termed as the slabbing cutter. These cutters have nicked teeth. The nicks are uniformly distributed on the entire periphery of the cutter.
The object of the nicks is to break up the chips and enable the cutter to take coarse feed. The plain milling cutters are available in diameters from 16 to mm and the width of the cutters range from 20 to mm Fig. The light-duty plain milling cutters have a face width less than 20 mm and are made with straight teeth parallel to the axis. The wider cutters are made with helical teeth, with a helix angle of fewer than 25 degrees.
These are relatively fine-tooth cutters. The helical duty plain milling cutters are wider cutters and are used for heavy-duty work. The helical angle of the teeth ranges from 25 to 45 degree. The cutters have fewer teeth on the periphery that increases chip space allowing them to take deeper cuts. They are also known as coarse tooth milling cutters. The helical plain milling cutters have further coarse pitch and the helix angle of the teeth ranges from 45 to 60 degree.
The cutter is useful in profile milling work due to its smooth cutting action and is adapted for taking light cuts on soft steel or brass and where wide surfaces are to be machined. The side milling cutter has teeth on its periphery and also on one or both of its sides.
This types of milling cutters are intended for removing metals from the side of a work a side milling cutter. The side milling cutter. The side milling cutters are available from 50 to mm in diameter and the width of the cutter ranges from 5 to 32 mm. The different types of side milling cutters are described below. The plain side milling cutter has straight circumferential teeth and has side teeth on both of its sides. Two or more such cutters may be mounted on the arbour and different faces of the workpiece may be machined simultaneously.
These cutters have an alternate tooth with opposite helix angle and are made of high-speed steel for long lasting durability. This design of the cutter teeth maximizes the chip space to a great extent.
The cutter is suitable for milling deep, narrow slots or keyways on workpieces. The half side milling cutter has straight or helical teeth on its circumferential surface and on one of its sides only. The periphery teeth do the actual cutting, whereas the side teeth size and finish the work. While straddle milling, when two half side milling cutters are mounted on the arbor at a fixed distance apart to mill the two end faces of the work simultaneously, the cutters are chosen with one having right-hand helical teeth and the other having left-hand helix to counter-balance the end thrust on the arbor.
The interlocking side milling cutters are formed out of two half side milling cutters or two staggered which are made to interlock to form one unit. The teeth of the two cutters may be plain or of paths of the teeth overlap when the cutters are assembled. The cutters are used for milling cutters wider slots of accurate width.
The width of the cutter may be varied by inserting spacers of suitable thickness between the two halves of the cutters.
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