Week 7 Computer controlled machining

7. Computer-Controlled Machining

What is computer controlled machining?

Computer-Controlled Machining (CCM) represents the cutting edge of manufacturing technology, blending precision engineering with computer science to revolutionize the way we create objects. By harnessing the power of computers to control machine tools, CCM allows for the creation of intricate and complex designs with unparalleled accuracy and efficiency. This technology has transformed industries ranging from aerospace to automotive, enabling the production of lighter, stronger, and more durable parts and components. With its ability to create virtually any shape imaginable, CCM is driving innovation across a wide range of fields, from architecture to art, pushing the boundaries of what is possible and inspiring a new generation of makers and manufacturers.

Different Computer controlled Machines

Computer-Controlled Machines come in various types, each tailored for specific applications and materials. Here are some different types:

CNC Mills: CNC milling machines use rotary cutting tools to remove material from a workpiece, typically in a subtractive manufacturing process. They are versatile and can produce complex shapes with high precision.
CNC Lathes: CNC lathes are used for machining cylindrical parts by rotating the workpiece against cutting tools. They are commonly used for creating symmetrical components such as shafts and bushings.
CNC Routers: CNC routers are similar to mills but are typically used for cutting softer materials like wood, plastic, and foam. They are commonly used in woodworking, sign making, and prototyping.
CNC Plasma Cutters: CNC plasma cutters use a high-velocity jet of ionized gas to cut through electrically conductive materials such as steel, aluminum, and brass. They are commonly used in metal fabrication for cutting intricate shapes.
CNC Laser Cutters: CNC laser cutters use a focused laser beam to cut through various materials such as metal, wood, plastic, and fabric. They are highly precise and are used in industries ranging from manufacturing to jewelry making.
CNC Waterjet Cutters: CNC waterjet cutters use a high-pressure stream of water mixed with abrasive particles to cut through materials. They are versatile and can cut through a wide range of materials, including metal, stone, glass, and composites.

Tasks

This week has following tasks:

Group assignment: do your lab's safety training test runout, alignment, fixturing, speeds, feeds, materials, and toolpaths for your machine. Here is our work of group assignments.

Individual assignment: make (design+mill+assemble) something big (~meter-scale)

Rocker Chair

In this week I decided to manufacture a very interesting thing which is OVAL ROCKER CHAIR raster

The shape of an oval rocker chair is characterized by its unique combination of an oval-shaped seat and a curved rocker base. The oval seat is wider than it is deep, providing ample space for comfortable seating. The curved rocker base allows the chair to rock back and forth smoothly, providing a relaxing and soothing motion. Overall, the oval rocker chair has a sleek and modern appearance, with clean lines and a minimalist design. Its shape is both functional and aesthetically pleasing, making it a popular choice for contemporary interior design styles.

raster

Material Used for this

Teak: Known for its durability and natural resistance to termites and decay, teak is a popular choice for furniture and carving due to its beautiful grain and color.
Rosewood: Rosewood, especially Indian rosewood (Sheesham), is prized for its rich, dark color and strong, durable nature, making it ideal for furniture making and intricate carvings.
Sheesham: Also known as Indian rosewood, Sheesham is valued for its durability and distinctive grain patterns, making it a preferred choice for furniture and decorative items.
Sal: Sal wood is commonly used for furniture and carving due to its strength and durability, as well as its resistance to decay and termite attacks.
Deodar: Deodar wood, sourced from the Himalayan cedar tree, is known for its light color and durability, making it suitable for furniture and carving applications.
Marine Plywood: Marine plywood is a high-quality plywood that is specifically designed for use in environments where it is exposed to moisture. It is often used in marine applications and for outdoor furniture.
Commercial Plywood: Commercial plywood is a versatile and cost-effective plywood that is suitable for a wide range of applications, including furniture making and interior decoration.
Hardwood Plywood: Hardwood plywood is made from hardwood veneers and is known for its strength and durability. It is commonly used in furniture making and other applications where strength and durability are important.

Material that I used:

12mm plywood refers to a type of plywood that has a thickness of 12 millimeters. Plywood is a sheet material manufactured from thin layers or "plies" of wood veneer that are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. This cross-graining technique improves the strength and stability of the plywood and reduces shrinkage and expansion. 12mm plywood is a versatile material used in various applications such as furniture making, cabinetry, interior decoration, and construction. Its thickness makes it suitable for a wide range of projects where strength and durability are required, but where a thinner material may be too flimsy. In furniture making, 12mm plywood can be used to create sturdy shelves, cabinets, and other furniture pieces. In construction, it can be used for wall sheathing, roofing, and subflooring. The thickness of 12mm plywood strikes a balance between strength and weight, making it easy to handle and work with while providing sufficient structural support for many applications.

Different Tools Used

There are several types of end mills used for cutting plywood on computer-controlled machines like CNC routers. Some common types include:

Upcut End Mills: These end mills pull chips up and out of the workpiece, which can help prevent chip buildup in the cut and provide a cleaner edge when cutting plywood.

Downcut End Mills: These end mills push chips down into the workpiece, which can help reduce tear-out on the top surface of the plywood when cutting through the material.

Compression End Mills: These end mills feature a combination of upcut and downcut flutes. The upcut portion helps pull chips out of the cut, while the downcut portion helps compress the top surface of the material, reducing tear-out.

Spiral Flute End Mills: These end mills have a spiral flute design that helps evacuate chips from the cut more efficiently, reducing the likelihood of chip buildup and improving cutting performance in plywood.

O-Flute End Mills: These end mills have a single, large flute that helps remove chips quickly from the cut, making them ideal for cutting soft materials like plywood.

Straight Flute End Mills: These end mills have a straight flute design that provides good chip evacuation and cutting performance in plywood.

Tool that I used

A 6mm flat end mill tool for plywood on a CNC router is a common choice for cutting and milling operations. This tool has a flat bottom and a cutting diameter of 6mm, making it suitable for various tasks such as cutting profiles, pockets, and general shaping of plywood.

When using a 6mm flat end mill tool for plywood on a CNC router, consider the following:

Speed and Feed Rates: Plywood is a relatively soft material, so you can typically use higher speed and feed rates compared to harder materials. However, it's essential to balance these settings to avoid overheating or burning the plywood.
Cut Depth: When cutting plywood with a 6mm flat end mill, consider the optimal depth of cut for your specific router and plywood type. Cutting too deep in a single pass can stress the tool and lead to poor cut quality.
Tool Path Strategy: Depending on your cutting requirements, you may choose different toolpath strategies such as conventional milling, climb milling, or adaptive clearing. Each strategy has its advantages and is suited to different cutting scenarios.
Chip Evacuation: Ensure that the CNC router's dust collection system is effective in evacuating chips and dust generated during cutting. This helps maintain a clean cutting environment and prevents chip buildup, which can affect cut quality.

Procedure

1.Solid Modeling of parts of chair in solid works

Rest

base

legs

2.Save file as .DXF

3. Import file in vcarve:VCarve11.55 Pro is a complete software solution for CNC routing, sign making and engraving. This is the software many professional sign shops and fabricators use. After importing joined all open ends.

4. Select the size of layout.

5. Tool Selection:Here we selected 6mm diameter flat end mill tool with two flutes.Tool speed is 16000rpm. automatically software has calculted chip loan and feed rate.