CNC Routing

CNC routing is a cutting process in which material is removed from a sheet by a rotating tool.

In CNC routing the cutting tool is moved mainly in two dimensions (except for plunging on the Z axis) to achieve the desired part shape. In CNC routing the cutting tool usually rotates about an axis that is perpendicular to the table that holds the material to be cut. A cutting tool hovers over the material from a rotating spindle. A sheet of material is placed on a stationary table below the cutter. While the cutting tool turns, a computer controls the motion of the cutter. The cutter is guided to move through the material, removing portions to create shapes.

There are several benefits of CNC routing. The process is cost effective for short runs as setup time is minimal. Complex shapes and high dimensional tolerances are possible. Smooth finishes can be achieved. CNC routing can produce almost any 2D shape provided inside corners have a reasonable radius.

Examples of parts made by CNC routing include: sheet metal enclosures, decorative signs, sign lettering, sheet metal mechanisms, etc.

CNC routing can process most rigid materials including most metals: Aluminum, Stainless Steel, Copper, Steel, Brass, Titanium,Sterling Silver, Bronze, etc. plus hard plastics and other materials: Nylon, Acetal, Polycarbonate, Polystyrene, Acrylic, Fiberglass,Carbon fiber, Teflon, ABS, PVC, Wood, etc.

Cost reduction options include reducing the total cut length, limiting complexity and avoiding intricate features.

CNC Routing Design Considerations

• Providing corner radius of the greater of .125" and 15% of sheet thickness is ideal.
• Avoid flimsy shapes such as long thin shapes and thin walls.

Electrochemical Machining

Electrochemical machining machine

Rotor formed by electrochemical machining

Overview of electrochemical machining

Bracket formed by electrochemical machining

Electrochemical machining (ECM) is a method of creating metal shapes by removing metal using an electrochemical process. A direct current with high density and low voltage is passed between a workpiece (the anode) and a pre-shaped tool (the cathode). At the anodic workpiece surface, metal is dissolved and thus the tool shape is copied into the workpiece.

Electrochemical machining creates components that are not subject to either thermal or mechanical stress and brittle material can be machined easily as there is no contact between the tool and workpiece. Electrochemical machining can create normal and delicate 3D shapes. Some example of parts that are made using electrochemical machining include dies, molds, turbine and compressor blades, cavities, holes, slots, etc. Electrochemical machining can process most types of conducting materials and alloys. Custom tooling is required in the negative of the desired part shape.

Various industrial techniques have been developed on the basis of of the process including:

• Electrochemical cutting
• Electrochemical ECM
• Electrochemical broaching
• Electrochemical drilling
• Electrochemical deburring

CNC Bending Machine

CNC Bending

CNC bending forms angles in sheet metal.

A workpiece is positioned over a die block and formed by the punch as it is forced into the die cavity.

Bracked Formed by CNC Bending

Example parts

Brackets, enclosures, and chassis.

CNC bending is a process where sheet metal is bent to an angle using, typically a V shaped punch and die. The sheet is placed between the punch and die which presses down on the sheet. CNC bending provides a low cost method to product 3D shapes from 2D sheets.

CNC bending is a suitable for processing most ductile metals and primarily for sheet metal designs with one or more bends. Just a few examples of CNC bending applications are brackets, enclosures, cams, chassis, etc. There is generally no special tooling required for CNC bending, with the exception of intricate designs and special bends.

CNC Bending Cost Reduction Tips

• Reduce the number of bends in design.
• Design parts to pack efficiently. For example, in designing a large box consider making the sides of the box separate with bolted flanges.
  
• Avoid complex bend combinations.
  
• Avoid the cost of bending by adding slots in place of the bends and then bend manually. Such parts also have lower shipping costs and take less storage space. (To create the slots use a few thin rectangular cutouts in place of each bend line.)
  
• Avoid odd angles.
  
• Provide straight edges that are parallel to the bend.
  

CNC Bending Design Considerations

• The minimum distance from the bend to the edge should be at least 4 times the material thickness plus the bending radius.
  
• Holes or slots should be located a minimum of 3 stock thickness plus the bend radius. If it is necessary to have holes closer, then the hole or slot should be extended beyond the bend line.
  
• Allow for variation in bend position, radius and angle.

CNC water Jet

CNC Waterjet Cutting

Water jet cutting machine

Water jet cuttiing of hole matrix

Water jet cutting of bicycle sprocket

Waterjet cutting of hexagon base

Waterjet cutting of wing ribs

CNC waterjet cutting is a process that produces shapes by cutting sheet material using a high pressure stream of water containing abrasive particles.

CNC waterjet cutting is an economical way to cut 2D shapes in a very wide range of materials with no tooling costs. The unique process of CNC waterjet cutting provides reasonably good edge quality, no burrs and usually eliminates the need for secondary finishing processes. The process also generates no heat so the material edge is unaffected and there is no distortion. CNC waterjet cutting can cut single or multi-layer materials from as thin as .001" to as thick as several inches. The process yields no poisonous gas when cutting plastics or rubber.

Shapes possible with CNC waterjet cutting include 2D shapes with cutouts of almost any complexity. Examples of parts that are often cut using CNC waterjet cutting include:

• Custom Enclosures
• Custom Metal Brackets
• Custom Robot Parts
• Custom washers
• Custom Front Panels
• Custom Sheet Metal Boxes
• Custom Motorcycle Parts
• Custom Auto Parts
• Mechanisms
• Chassis
• etc.
  

Materials applicable to waterjet cutting include almost any material, hard or soft including:

• Aluminum
• Stainless Steel
• Copper
• Nylon
• Steel
• Acetal
• Polycarbonate
• Polystyrene
• Fiberglass
• Brass
• Carbon fiber
• Teflon
• Titanium
• ABS
• PVC
• Sterling Silver
• Spring Steel
• Bronze
• Rubber Parts
• Foam
• Marble
• Laminates
• Gasket material
• Wood
• Granite
• Ceramics
• Glass
• etc.
  

Very few materials are impractical including some types of glass and some types of wood.

No custom tooling is normally needed in CNC waterjet cutting. Cost reduction options include reduction of total cut length, reduction in number of holes and cutouts and reduction of material hardness and thickness.

CNC Waterjet Cutting Design Considerations

• Edges are good but usually not as smooth as milling or punching.
  
• Some spots along the edge, such as where the cut ends, may be less smooth.
  
• The edges of the cut part generally have a dull finish.
  
• Kerf width is typically ~.060", hence inside corners will be rounded to ~.03" radius.
  
• There may be some hazing on the surface - especially near the edges.
  
• Thin flimsy structures and shapes where a high proportion of material is removed may present difficulty in meeting dimensional and flatness tolerances.
  
• Edges will be slightly sloped - the bottom side will have slightly more material at the edge than the dimensioned top side.

Waterjet Cutting - Click here for more amazing videos

CNC 5 Axis Machine

5 Axis CNC Cylinder Head Porting Machine - Funny videos are here

5 axis CENTROID CNC Cylinder Head Porting Machine making cylinder heads. Patented designs for incredible accuracy. Mastercam CAD/CAM used to create tool paths. Digitize and reproduce your race wining designs.

CNC Software/Mastercam

Founded in Massachusetts in 1983,CNC Software, Inc. is one of the oldest developers of PC-based computer-aided design / computer-aided manufacturing (CAD/CAM) software. They are one of the first to introduce CAD/CAM software designed for both machinists andengineers. Mastercam, CNC Software’s main product, started as a2D CAM system with CAD tools that let machinists design virtual parts on a computer screen and also guidedcomputer numerical controlled (CNC) machine tools in the manufacture of parts. Since then, Mastercam has grown into the most widely used CAD/CAM package in the world.CNC Software, Inc. is now located inTolland, Connecticut.

Mastercam’s comprehensive set of predefined toolpaths—including contour, drill, pocketing, face, peel mill, engraving, surface high speed, advanced multiaxis, and many more—enable machinists to cut parts efficiently and accurately. Mastercam users can create and cut parts using one of many supplied machine and control definitions, or they can use Mastercam’s advanced tools to create their own customized definitions.

Mastercam also offers a level of flexibility that allows the integration of 3rd party applications, called C-hooks, to address unique machine or process specific scenarios.

Mastercam's name is a double entendre: it implies mastery of CAM (computer-aided manufacturing), which involves today's latest machine tool control technology; and it simultaneously pays homage to yesterday's machine tool control technology by echoing the older term master cam, which referred to the main cam or model that a tracer followed in order to control the movements of a mechanically automated machine tool.

Conventional Mill Operation

Crash Course in Milling, Chapter 2 - Conventional Mill Operation, by Glacern Machine Tools from Glacern Machine Tools on Vimeo.

Conventional Milling Machine

The Milling Machine uses a rotating milling cutter to produce machined surfaces by progressively removing material from a work piece. The vertical milling machine also can function like a drill press because the spindle is perpendicular to the table and can be lowered into the work piece.

THE CONTROLS START/STOP The green button starts the spindle motor and the red button shuts the motor off. Variable Motor Drive used on some of the Milling Machines FORWARD/REVERSE This switch changes the rotation direction of the spindle. When the milling machine is in high range this switch is in the forward position for cutting but in low range the switch is in the reverse position. Putting the switch in the opposite position while remaining in the same range reverses the rotation of the spindle. HAND BRAKE Also known as the spindle brake, it is used to bring the spindle rotation to a stop after the power is turned off and to aid in removing collets and chucks. The spindle can be locked by pressing or pulling the brake and then pushing it up. SPINDLE SPEED This wheel is used to change the speed of the spindle for both high range and low range. The milling machine must be running when changing the speed. POWER FEED The power feed uses a motor to control the motion of the longitudinal feed in either direction at various speeds. Not all of the milling machines in the shop have this option. CROSS-FEED HANDWHEEL This handwheel moves the table in and out. VERTICAL FEED HANDCRANK This is used to raise and lower the table. LONGITUDINAL HANDWHEEL This handwheel moves the table left and right. On some machines the handles are spring activated to keep them from rotating when the power feed is used. HIG-LOW SPEED CONTROL The high-low speed switch changes the range from high to low and vise-versa. The spindle may need to be turned by hand while engaging the gears. QUILL FEED HANDLE You can raise and lower the quill (spindle) with this handle. QUILL LOCK Pushing this lever down will lock the quill, pulling it back up releases the lock. The quill must be locked when milling. QUILL STOP The quill stop can be adjusted by hand to set a limit on the quill travel is also used to disengage the quill feed. This is useful when multiple holes have to be drilled to the same depth. QUILL FEED LEVER AND SELECTOR These are used to activate the power feed for the quill. The selector will adjust the speed of the power feed and the lever activates the drive. The quill feed can

DIGITAL READOUT These readouts were added to the milling machines to aid in the accuracy of cuts and increase productivity. The lateral movement of the table can be measured to 2/10,000th of an inch with the readouts. Other operations the readout can perform include dividing any dimension by two, running with absolute or relative measurements, and displaying in inches or millimeters.

LONGITUDINAL/CROSS-FEED AXIS The digital readout will display the distance traversed in both the X and Y axis. ZERO BUTTONS These two buttons will set their respective displays to zero. This is used after the machinist finds the edge of their part and wants to reference all of the other measurements off that axis. INCHES/METRIC BUTTON The readout can give all measurements in inches or millimeters, by pressing this button it will switch from one system of measurement to the other. KEYPAD Dimensions can be entered into the readout using the keypad. This can be helpful when a reference point is needed other than zero.

Peripheral and Face Milling Techniques

Fig. 1

Peripheral milling uses teeth on the outer edge of the cutter body. The surface produced corresponds to the contour of the milling cutter, which can range from a flat surface to a formed shape. There are two different methods of peripheral milling, Conventional or Up Milling and Climb or Down Milling. The figures on the left show the rotation of the cutting tool with respect to the direction of the part on the table. In conventional milling the work is fed against the cutter which compensates for backlash in the table. Each tooth of the cutting tool starts its cut in clean metal, prying the material off the work. Down milling will give a better quality of work and is better suited for thin pieces of material since the cutting action forces the work into the table. This method should not be used on hard materials and the machine has to be rigid so backlash cannot occur. The cutting tool will also last longer using Down milling as long as good tool pressure is maintained. The machines in the shop are suitable for both types of milling. If you are unsure of which method you should use ask somebody in the shop for assistance. Face milling uses the bottom of the mill to machine the work instead of the sides. The cutting comes from the combined action of cutting edges located on the face (or end) of the cutting tool as well as the edges on the periphery. The direction of the feed with relation to the rotation is not important when using this method.