CNC router

Last updated
Large 5-axis moving table CNC router DMS CNC router at SITU Fabrication (12480).jpg
Large 5-axis moving table CNC router
Drawing of a Tabletop DIY - CNC router. Silver: Iron, Red: Stepper Motors, Light Brown: MDF, Dark Brown: Hard Wood Homebuild cnc colored.png
Drawing of a Tabletop DIY - CNC router. Silver: Iron, Red: Stepper Motors, Light Brown: MDF, Dark Brown: Hard Wood

A computer numerical control (CNC) router is a computer-controlled cutting machine which typically mounts a hand-held router as a spindle which is used for cutting various materials, such as wood, composites, metals, plastics, glass, and foams. CNC routers can perform the tasks of many carpentry shop machines such as the panel saw, the spindle moulder, and the boring machine. They can also cut joinery such as mortises and tenons.

Contents

A CNC router is very similar in concept to a CNC milling machine. Instead of routing by hand, tool paths are controlled via computer numerical control. The CNC router is one of many kinds of tools that have CNC variants.

CNC Dynamics Pattern Maker Pattern Maker.jpg
CNC Dynamics Pattern Maker

Applications

A CNC router can be used to produce items such as door carvings, interior and exterior decorations, wood panels, sign boards, wooden frames, moldings, musical instruments, furniture. In addition, they see use in industry in the thermoforming of plastics by automating the trimming process. CNC routers can help ensure part repeatability and sufficiently efficient output for production, or allow one-off designs to be made.

Use

Control panel for a large DMS 5-axis CNC router DMS CNC router at SITU Fabrication (12504).jpg
Control panel for a large DMS 5-axis CNC router

CNC routers are controlled by a computer. Coordinates are uploaded into the machine controller from a separate program. CNC router are often used with two software applications—one to make designs (CAD) and another to translate those designs into a G-code or M-code program of instructions for the machine (CAM) in vertical, horizontal and perpendicular coordinates. As with CNC milling machines, CNC routers can be controlled directly by manual programming, but CAD/CAM allows wider possibilities for contouring, speeding up the programming process and in some cases creating programs whose manual programming would be impractical. On some controllers the G-code can be loaded as a vector file on the router control panel. A vector file can be created from a picture file by using a drawing (CAD) software.

The human operator selects the machine tool (such as a 14-inch (6-MM) v-bit or a 34-inch core box bit), speed, cut depth and tool path. For cut path, most machines give the options of tracing the vectors, cutting outside the vectors, or cutting inside the vectors. The operator determines the center point of the part, clamps the part onto the table, moves the bit directly above the marked center and down to the face of the part, and marks this as the starting point. The operator moves the bit up a few inches and selects the run G-code function. The machine begins to cut the design.

Computer-aided manufacturing

CAM software makes the CAD drawing/design into a code called G-code. The illustration shows what a bare-bones CNC machine might look like without its computer controller.

Sizes and configurations

CNC routers come in many configurations, from small home-style D.I.Y. "desktop", to large industrial routers manufactured for commercial use. CNC routers are used in sign shops, cabinet making, aerospace and boat-making.

Although there are many configurations, most CNC routers have a few specific parts: a dedicated CNC controller, one or more spindle motors, servo motors or stepper motors, servo amplifiers, AC inverter frequency drives, linear guides, ball screws and a workspace bed or table.

In addition, CNC routers may have accessories such as vacuum pumps, with grid table tops or t-slot hold down fixtures to hold the parts in place for cutting. CNC routers are typically available in 3-axis and 5-axis CNC formats. Many manufacturers offer A and B axis for full 5-axis capabilities and rotary 4th axis. Common industrial CNC router sizes include 4 × 8 feet and 5 × 10 feet.

Many CNC routers today are made of aluminum extrusion which provide great flexibility as this can be shipped from almost anywhere unassembled but also provides size options. Some popular extrusion used are MakerSlide, V-Slot linear rail, and 8020 T-Slotted profile.

Materials

Wood

A typical CNC wood router CNC Router.png
A typical CNC wood router

A CNC wood router is a computer-controlled router tool that carves/etches objects or images into the face of a piece of wood. [1] The CNC Router is ideal for hobbies, engineering prototyping, product development, art, and production works. The CNC works on the Cartesian coordinate system (X, Y, Z) for 3D motion control; however, typical CNC operated systems can only make carvings on flat planes. The machine sits on a track and is not capable of making round or spherical cuts. Parts of a project can be designed in the computer with a CAD/CAM program, and then cut automatically using a router or other cutters to produce a finished part. In some instances, the table will not come with a router included. This allows the user to change out routers for different applications. For lighter strained cuts, they could use a lower grade router but for more intensive applications.

Metal

Milling is the machining process of using rotary cutters to remove material [2] from a workpiece advancing (or feeding) in a direction at an angle with the axis of the tool. [3] [4] It covers a wide variety of operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes in industry and machine shops today for machining parts to precise sizes and shapes.

Stone

A stone CNC router is a type of CNC router machine designed for marble, granite, artificial stone, tombstone, ceramic tiles, glass machining, polishing for arts and crafts, etc. Wood, metal and stone require different "bits" or "inserts". There is bit call as diamond tools with different diameter 4mm, 6mm, 8mm mainly used. For wood CNC-ing, bits with sharp cutting edges are used, while for Stone CNC-ing, the bits are made of a metal bar with a sintered layer of extremely hard but roughly shaped particles. Routing CNC is more like grinding than cutting.

Because stone dust is very abrasive, these routers also have much better protection for the guide rails (below cover). With "wood" routers the guide rails are often visible from the outside & unprotected, while stone routers are fully covered.

Stone routers also have a water recirculation system. A small jet of water is pointed at the router bit and this captures almost all fine stone dust in the water, which then flows to a collection reservoir where the stone particles settle on the bottom.

Polyurethane foam

Polyurethane foam can also be cut using a CNC router in order to produce complex shapes which would otherwise be difficult or impossible to replicate by hand. Depending on the type of foam being converted, a CNC router would be able to cut through up to an 8lb density. By converting a CAD design file into a CAM file, the CNC Router is able to read relevant information and produce a highly accurate finished product.

Related Research Articles

<span class="mw-page-title-main">Router (woodworking)</span> Woodworking power tool

The router is a power tool with a flat base and a rotating blade extending past the base. The spindle may be driven by an electric motor or by a pneumatic motor. It routs an area in hard material, such as wood or plastic. Routers are used most often in woodworking, especially cabinetry. They may be handheld or affixed to router tables. Some woodworkers consider the router one of the most versatile power tools.

<span class="mw-page-title-main">Computer-aided manufacturing</span> Use of software to control industrial processes

Computer-aided manufacturing (CAM) also known as computer-aided modeling or computer-aided machining is the use of software to control machine tools in the manufacturing of work pieces. This is not the only definition for CAM, but it is the most common. It may also refer to the use of a computer to assist in all operations of a manufacturing plant, including planning, management, transportation and storage. Its primary purpose is to create a faster production process and components and tooling with more precise dimensions and material consistency, which in some cases, uses only the required amount of raw material, while simultaneously reducing energy consumption. CAM is now a system used in schools and lower educational purposes. CAM is a subsequent computer-aided process after computer-aided design (CAD) and sometimes computer-aided engineering (CAE), as the model generated in CAD and verified in CAE can be input into CAM software, which then controls the machine tool. CAM is used in many schools alongside CAD to create objects.

<span class="mw-page-title-main">Metalworking</span> Process of making items from metal

Metalworking is the process of shaping and reshaping metals to create useful objects, parts, assemblies, and large scale structures. As a term it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale: from huge ships, buildings, and bridges down to precise engine parts and delicate jewelry.

<span class="mw-page-title-main">Numerical control</span> Computer control of machine tools

In machining, numerical control, also called computer numerical control (CNC), is the automated control of tools by means of a computer. It is used to operate tools such as drills, lathes, mills, grinders, routers and 3D printers. CNC transforms a piece of material into a specified shape by following coded programmed instructions and without a manual operator directly controlling the machining operation.

G-code is the most widely used computer numerical control (CNC) and 3D printing programming language. It is used mainly in computer-aided manufacturing to control automated machine tools, as well as for 3D-printer slicer applications. The G stands for geometry. G-code has many variants.

<span class="mw-page-title-main">Printed circuit board milling</span> Milling process for PCBs

Printed circuit board milling is the milling process used for removing areas of copper from a sheet of printed circuit board (PCB) material to recreate the pads, signal traces and structures according to patterns from a digital circuit board plan known as a layout file. Similar to the more common and well known chemical PCB etch process, the PCB milling process is subtractive: material is removed to create the electrical isolation and ground planes required. However, unlike the chemical etch process, PCB milling is typically a non-chemical process and as such it can be completed in a typical office or lab environment without exposure to hazardous chemicals. High quality circuit boards can be produced using either process. In the case of PCB milling, the quality of a circuit board is chiefly determined by the system's true, or weighted, milling accuracy and control as well as the condition of the milling bits and their respective feed/rotational speeds. By contrast, in the chemical etch process, the quality of a circuit board depends on the accuracy and/or quality of the mask used to protect the copper from the chemicals and the state of the etching chemicals.

<span class="mw-page-title-main">CNC wood router</span> CNC router tool

A CNC wood router is a CNC router tool that creates objects from wood. CNC stands for computer numerical control. The CNC works on the Cartesian coordinate system for 3D motion control. Parts of a project can be designed in the computer with a CAD/CAM program, and then cut automatically using a router or other cutters to produce a finished part. The CNC router is ideal for hobbies, engineering prototyping, product development, art, and production work.

<span class="mw-page-title-main">Speeds and feeds</span> Two separate velocities in machine tool practice, cutting speed and feed rate

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.

<span class="mw-page-title-main">Tool and cutter grinder</span>

A Tool and Cutter Grinder is used to sharpen milling cutters and tool bits along with a host of other cutting tools.

<span class="mw-page-title-main">Metal lathe</span> Machine tool used to remove material from a rotating workpiece

In machining, a metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called lathes, or else referred to by more-specific subtype names. These rigid machine tools remove material from a rotating workpiece via the movements of various cutting tools, such as tool bits and drill bits.

Digital modeling and fabrication is a design and production process that combines 3D modeling or computing-aided design (CAD) with additive and subtractive manufacturing. Additive manufacturing is also known as 3D printing, while subtractive manufacturing may also be referred to as machining, and many other technologies can be exploited to physically produce the designed objects.

<span class="mw-page-title-main">STEP-NC</span> Machine tool control language

STEP-NC is a machine tool control language that extends the ISO 10303 STEP standards with the machining model in ISO 14649, adding geometric dimension and tolerance data for inspection, and the STEP PDM model for integration into the wider enterprise. The combined result has been standardized as ISO 10303-238.

<span class="mw-page-title-main">Multiaxis machining</span> Manufacturing processes using tools that can move in 4 or more directions

Multiaxis machining is a manufacturing process that involves tools that move in 4 or more directions and are used to manufacture parts out of metal or other materials by milling away excess material, by water jet cutting or by laser cutting. This type of machining was originally performed mechanically on large complex machines. These machines operated on 4, 5, 6, and even 12 axes which were controlled individually via levers that rested on cam plates. The cam plates offered the ability to control the tooling device, the table in which the part is secured, as well as rotating the tooling or part within the machine. Due to the machines size and complexity it took extensive amounts of time to set them up for production. Once computer numerically controlled machining was introduced it provided a faster, more efficient method for machining complex parts.

<span class="mw-page-title-main">WorkNC</span>

WorkNC is a Computer aided manufacturing (CAM) software developed by Sescoi for multi-axis machining.

<span class="mw-page-title-main">Guitar manufacturing</span>

Guitar manufacturing is the use of machines, tools, and labor in the production of electric and acoustic guitars. This phrase may be in reference to handcrafting guitars using traditional methods or assembly line production in large quantities using modern methods. Guitar manufacturing can also be broken into several categories such as body manufacturing and neck manufacturing, among others. Guitar manufacturing includes the production of alto, classical, tenor, and bass tuned guitars.

LinuxCNC is a free, open-source Linux software system that implements numerical control capability using general purpose computers to control CNC machines. It's mainly intended to run on PC AMD x86-64 systems. Designed by various volunteer developers at linuxcnc.org, it is typically bundled as an ISO file with a modified version of Debian Linux which provides the required real-time kernel.

<span class="mw-page-title-main">Automatic lathe</span>

In metalworking and woodworking, an automatic lathe is a lathe with an automatically controlled cutting process. Automatic lathes were first developed in the 1870s and were mechanically controlled. From the advent of NC and CNC in the 1950s, the term automatic lathe has generally been used for only mechanically controlled lathes, although some manufacturers market Swiss-type CNC lathes as 'automatic'.

<span class="mw-page-title-main">Milling (machining)</span> Removal of material from a workpiece using rotating tools

Milling is the process of machining using rotary cutters to remove material by advancing a cutter into a workpiece. This may be done by varying directions on one or several axes, cutter head speed, and pressure. Milling covers a wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes for machining custom parts to precise tolerances.

The history of numerical control (NC) began when the automation of machine tools first incorporated concepts of abstractly programmable logic, and it continues today with the ongoing evolution of computer numerical control (CNC) technology.

<span class="mw-page-title-main">NCSIMUL</span>

NCSIMUL is a software program developed by the company SPRING Technologies, that is used for simulating, verifying, and optimizing CNC machining in a 3-step process. It reads the post-processed G-code to identify the tool path, and replicates the material removal process of the machine by cutting volumes. It then identifies all syntax errors in the code, crashes in the machining environment, and deviations from the modeled CAD part.

References

  1. "15 Best CNC Routers". 21 February 2021. Retrieved 2021-09-05.
  2. Brown & Sharpe 1914, p. 7.
  3. CMMC 1922, p. 122.
  4. Usher 1896, p. 142.