Tooling - Machining

Processes can include: machining, drilling, boring, turning, grinding, folding, broaching, reaming, boring, lapping, honing, etc.

The Principle behind Electrical Discharge Machining (EDM)
Simplified, the system is a two electrode system separated by a dielectric medium. The wire is one electrode and the workpiece being machined is the other. EDM machining utilizes a voltage across these two electrodes which is greater than the breakdown voltage across the gap between the workpiece and the wire. This breakdown voltage is a function of the distance between the wire and workpiece, the insulating properties of the dielectric (fluid separating the electrodes), and the degree of pollution of the gap.
Extrude Hone Corporation
Hausermann Abrading Process Co.
Hausermann Controls Co.

Sheet metal forming
Sheet metal forming is a grouping of many complemetary processes that are used to form sheet metal parts. One or more of these processes is used to take a flat sheet of ductile metal, and mechanically apply deformation forces that alter the shape of the materia. Before deciding on the process(es), one should determine whether a particular sheet metal can be formed into the desired shape without failure.
St. Lawrence Press
Greenerd Press & Machine Company, Inc.
Campbell Grinder Company

Casting
* Casting-Die
Molten metal is forced into the die cavity at pressures ranging from 0.7 to 700 MPa. When the metal solidifies the die halves open and the casting is ejected.

* Casting-Investment
Metal mold makes wax or plastic replica of the piece to be cast. These replica are spruced, then surrounded with investment material, baked out, and metal is poured in the resultant cavity. Molds are broken to remove the castings.
See Investment Casting

* Casting-Sand
Tempered sand is packed onto wood or metal pattern halves, removed from the pattern, and assembled with or without cores, and metal is poured into resultant cavities. Various core materials can be used. Molds are broken to remove castings. Specialized binders now in use can improve tolerances and surface finish.

* Casting-Shell
Resin-coated sand is poured onto hot metal patterns, curing into shell-like mold halves. These are removed from the pattern and assembled with or without cores. Metal is poured into resultant cavities. Molds are broken to remove castings.

* Casting-Slip
In slip casting - sometimes called drain casting - a plaster of paris mold is filled with a slip. Slip is a liquid containing a ceramic material in a water suspension. As the mold absorbs water, the ceramic suspension solidifies uniformly on the walls of the mold. Once the desired wall thickness is reached, the remaining slip is drained, the mold is separated or broken, and the part is removed. The part, now in a powder compact or green stage, is then sintered in an oven.

* Casting-Centrifugal
In centrifugal casting, a permanent mold is rotated about its axis at high speeds (300 to 3000 rpm) as the molten metal is poured. The molten metal is centrifugally thrown towards the inside mold wall, where it solidifies after cooling. The casting is usually a fine grain casting with a very fine-grained outer diameter, which is resistant to atmospheric corrosion, a typical situation with pipes. The inside diameter has more impurities and inclusions, which can be machined away.

Extrusion
Extrusion is a process that forces metal to flow through a shape-forming die. The metal is plastically deformed under compression in the die cavity. Extrusion processes can be carried on hot or cold. Extrusion differs from drawing in that the metal is pushed, rather than pulled under tension. See Extrusion

FDM
Fused Deposition Modelling is a non-laser based rapid prototyping process that produces three dimensional solid objects directly from CAD models. The machine is basically a CNC controlled robot carrying a miniature extruder head. The solid objects are built "string by string" by feeding the head with a plastic wire. Once in the head, the wire is heated to just above its melting temperature, and it is deposited onto the previous layer of wire. Once in contact with the cold layer underneath, the wire immediately freezes and adheres to the underlying layer.

Forging
Forging denotes a family of processes by which plastic deformation of the workpiece is carried out by compressive forces, at room temperature, or at elevated temperatures, hence the terms cold and hot forging. Simple forging can be made with a heavy hammer and an anvil using techniques that have been available for centuries. However, usually a set of dies and a press are required.

Milling
Milling is one of the most versatile processes. Milling uses a multitooth cutter that rotates along various axes with respect to the workpiece. Milling includes a number of versatile machining operations, which are capable of producing a variety of configurations using a milling cutter.
Bohle Machine Tools, Inc.
Cincinnati Machine
The Crankshaft Machine Company
Crankshaft Machine Group
DoALL Company
Masco Machine, Inc.
Morey Machinery Manufacturing Corp



SLS (Laser Sintering)
The laser is used to sinter and fuse powder rather than solidify liquid polymer. Inside the SLS machine, a thin layer of powder is laid down and heated to just below its melting-point by infrared heating panels at the side of the chamber. The unfused powder acts as built-in support as the part is lowered and the steps are repeated. SLS is a very localized phenomena. It differs from the baking-like sintering used in more traditional powder metallurgy.


Turning
Turning is one of the oldest and the most fundamental manufacturing processes. It is the machining of a round workpiece; the profile of the workpiece can be straight, conical, curved, or grooves, like shafts, spindles, pins, handles, and various machine components. In turning, the work piece is rotated and the cutting tool is stationary; this is different from another very old and traditional machining process, milling, where the cutting tool rotates and the workpiece moves in transition only.
Bridgeport Machines, Inc.
Daewoo Heavy Industries, America Corp.
Fryer Machine Systems, Inc.
Monarch Machine Tool Company, Inc.
Servo Products Company