Articles
CNC Machine Shop

Processes used in a CNC machine shop

CNC is short computer numeric controlled and a CNC machines shop is a shop that has computer operated machines and outsources this CNC functions to companies by performs various custom and project fabrications on behalf of their clients. CNC machines are machines that receives feeds from a computer program and execute certain tasks according to the design input into the machine. CNC machines are usually used in metal fabrication to cut metal, mold metal and finish the metal. There are various processes that a CNC machine shop undergoes to fulfill its functions in metal fabrication.


Programming services in the CNC machine shop


Once it receives a design or project from a client, the first step that a CNC machine shop does is to create a program that will enable the CNC machines to work in accordance with the clients design. The program is created in G- codes and M-codes according to the machine standards. The G-Codes are the codes that instruct the machine to 'go' and execute certain functions according to the program. These functions include cutting, bending, welding, shaping and other metal fabrication functions. The M-Code instructs the machine to change or stop from its current functions. It defines the end of a process and the function a machine needs to make at the end of the service. A computer aided design (CAD) is a software that enables you to design and have the designs interpreted by the machine and converted into numeric language.


CNC Machine shop process of loading the program

Once the desired program has been prepared, it is set to be uploaded into the machine. You can transfer the G- Codes and M-Codes to the machines in different modes depending on the machine technology. You can download the program data in the machine language into a flash-disk and then uploaded it into the machine. There are other CNC machine shop ways of having the design data transferred to the machine through advanced communication between the machines and the computer. Where the code data is a lot, punch tapes with microchips are usually used.


Running the machine in the CNC Machine shop

After uploading the desired design in the numeric machine language, the operator can proceed and position the CNC machine and materials in preparation for the job. The correct set-up may require some level of skills. Once everything is set, the CNC machine shop operator will proceed and switch on the machine. The machine should proceed and function in accordance with the imputed design. If the operator discovers any significant errors or malfunctions, they will switch off the machine immediately and reprogram the machine. However, if the machine operates correctly, the required batch will run as programmed.


Value add through CNC machine shops

CNC machine shops enable faster and more accurate fabrication of metals among other functions. The CNC machines have a greater output and can work 24 hours a day. The quality of the products is much higher and therefore CNC machine shops are definitely a significant value add to the metal fabrication industry.
 
Process used in CNC Machine shop

Processes used in a CNC machine shop
 

CNC is short computer numeric controlled and a CNC machines shop is a shop that has computer operated machines and outsources this CNC functions to companies by performs various custom and project fabrications on behalf of their clients. CNC machines are machines that receives feeds from a computer program and execute certain tasks according to the design input into the machine. CNC machines are usually used in metal fabrication to cut metal, mold metal and finish the metal. There are various processes that a CNC machine shop undergoes to fulfill its functions in metal fabrication.

Programming services in the CNC machine shop

Once it receives a design or project from a client, the first step that a CNC machine shop does is to create a program that will enable the CNC machines to work in accordance with the clients design. The program is created in G- codes and M-codes according to the machine standards. The G-Codes are the codes that instruct the machine to 'go' and execute certain functions according to the program. These functions include cutting, bending, welding, shaping and other metal fabrication functions. The M-Code instructs the machine to change or stop from its current functions. It defines the end of a process and the function a machine needs to make at the end of the service. A computer aided design (CAD) is a software that enables you to design and have the designs interpreted by the machine and converted into numeric language.

CNC Machine shop process of loading the program

Once the desired program has been prepared, it is set to be uploaded into the machine. You can transfer the G- Codes and M-Codes to the machines in different modes depending on the machine technology. You can download the program data in the machine language into a flash-disk and then uploaded it into the machine. There are other CNC machine shop ways of having the design data transferred to the machine through advanced communication between the machines and the computer. Where the code data is a lot, punch tapes with microchips are usually used.

Running the machine in the CNC Machine shop

After uploading the desired design in the numeric machine language, the operator can proceed and position the CNC machine and materials in preparation for the job. The correct set-up may require some level of skills. Once everything is set, the CNC machine shop operator will proceed and switch on the machine. The machine should proceed and function in accordance with the imputed design. If the operator discovers any significant errors or malfunctions, they will switch off the machine immediately and reprogram the machine. However, if the machine operates correctly, the required batch will run as programmed.

Value add through CNC machine shops

CNC machine shops enable faster and more accurate fabrication of metals among other functions. The CNC machines have a greater output and can work 24 hours a day. The quality of the products is much higher and therefore CNC machine shops are definitely a significant value add to the metal fabrication industry.

 
 
CNC Machining

  About CNC Machining

CNC stands for Computer Numerical Control. CNC machining is a modern machine processing that entails computer controlled machines that perform a wide variety of functions. In metal fabrication, CNC machining involves the use of computer driven machinery to perform such tasks as metal cutting, metal welding, shaping of the metal components and finishing the components.

The original metal fabrication machines were initially called numeric controlled (NC) and they were invented in the late 1950s by John T. Parsons  in conjunction with MIT University. The machines used G-Codes that gave the machines 'go' instructions. The G-Codes defined the positions of the machines and they instructed machines to perform specific functions. The machines were built for a specific function and it was quite hard changing the functionality of the machine. However, in 1970s, computers were incorporated into the machines to allow for different programs to be applied to a machine. This means that with a change of the controlling software, the machines can be reprogrammed to perform different functions. Today, CNC machining uses computer aided design (CAD) and computer aided machine (CAM) technology to execute their functions.

Types of CNC machining tools

CNC machining for milling are used to cut various materials including plastics, metals fabric and wood. They use G-codes program to define the processes of cutting, the depth of cuts and the various designs of cuts in the various materials. However, there are other milling machines that use propriety software as opposed to G-Codes to run the machines. Either way, the propriety software are intuitive and similar to G-Codes and operators can easily switch from one program to another.

CNC machining for grinding are machines that use a grinder to mold metal to the desired shape. The process is computerized and the machine is able to achieve various metal forms with precision and speed.

CNC machining for lathes is the process of using computer controlled equipment to cut through steel using the latest technology. The machine allows speed and accuracy while cutting metal pieces. It achieves dimensional tolerances that are not possible with the former manual method of lathing.

Reasons for using CNC machining

By automating processes by use of a computer, the various metal fabrication processes are achieved with great precision and accuracy. This enables for high quality produces, less wastage and faster production cycle. The CNC machining allow for 3D machining with the help of robots and other sophisticated equipment. CNC machine shops are able to fabricate large assignments in a short time.

Where to get CNC Machining services

There are various places you can get CNC machining services. These services are available with CNC machining shops. The shops enable customized fabrication of metal, development of prototypes and the also handle manufacturing lines for various manufacturers.

 
 

Understanding CNC G-Code and M-Code Programming

When a CNC Lathe or CNC Mill is properly programmed and set-up, it is a safe, productive, and high-quality method for production machining.

Today’s CNC Machine Shop likely produces it’s G-Code with the aid of a CAM(Computer Aided Manufacturing) software package. Cam software used the geometry from the part drawing or blueprint. It utilize the dimensions drawn into the part and assigns 2D or 3D geometry to the part. This geometry is then used by the Cam software. The CAM Programmer assigns a group of machining processes, like drilling, facing, boring, pocketing, etc. to the geometry in the drawing. Once this is done, the Software quickly and automatically generated the G-Code program to be used in the CNC machine. Often this program can be several thousand lines long.

The most popular Cam programs in use today are Mastercam, Gibbscam and BobCad. A Cam package price can range anywhere from $10,000 to $15,000 for a single seat of software.

Not every company is going to be able to purchase an expensive Cam software package to generate G-Code. However, even if a company has a Cam package, it will benefit from possessing a good general knowledge of G-Code and M-Code programming language. The knowledge will help understand what is going on in the machine you are operating. This knowledge may help to keep you safe, make you more productive, (and thereby more valuable and highly paid) or it may help you get a better job.

This is not meant to be an all-inclusive explanation of CNC G-code programming. It is meant to be a very basic primer. A first step to get you started on a pathway to a better understanding of CNC programming.

Usually a CNC program will consist of anywhere from a few lines of code for a simple job, to thousands of lines of code for a larger job. In this article we will focus on the simple, and shorter version.

Usually a CNC program will have N words at the beginning of lines in the program. N words may be at the beginning of every line, or they may be at the beginning of just a few lines.

N1
N2
N3

Sometimes you will see them as

N2
N4
N6

Or

N10
N20
N30

In every case, the purpose of the N word is simply to number the line or block of code. It is meant to help identify a specific line of code or a block of code. This can be important! Imagine trying to track down an error in a huge program of several thousand lines of code if you had no numbering system to go by!

Other than identifying a line…the N words are ignored by the CNC machine. Their only purpose is to be a method of identifying where you are at in the program. Think of N words as being similar to the page numbers of a book.

Often you may see a G00 or G0 (G Zero) used interchangeably. In most cases, when using a G number such as G00, G01, G02, G03, G04, etc., on up to G09, one would be able to use the single digit version of the command. Examples would be: G0, G1, G2, G3, G4, etc.. Almost all machines today will accept either this single digit version or the 2 digit version of this code. In the extremely rare case where an error is caused by a single digit version, or when in doubt, use the standard 2 digit version. Example G00.

What follows is a basic list of the most common G-Codes with a brief explanation of it’s use/purpose. It is not meant to be a complete list. This is also not meant to be complete description of each individual G-code’s use. When a G word offer’s more than one use, The most commonly used purpose to that G-code. In some cases a G word has a different use for lathe or mill. Again, the most commonly used G words are:

G00 Rapid Transverse Motion
G01 Motion by a feed rate
G02 Motion in an arc clockwise
G03 Motion in an arc counter clockwise
G04 Dwell
G
G17 XY Plane selection
G18 XZ Plane selection
G19 YZ Plane selection
G28 Return to Machine zero for axis selected
G
G
G
G
G
G40 Cutter compensation Cancel
G41 2D Cutter compensation Left
G42 2D Cutter compensation Right
G43 Tool length compensation + (add to tool length offset)
G44 Tool length compensation – (subtract tool length offset)
G49 Cancels G43 G44
G50 Sets a speed limit for Constant surface speed (lathe)
G52 Set Work Coordinate system
G54 Work coordinate system #1
G55 Work coordinate system #2
G56 Work coordinate system #3
G57 Work coordinate system #4
G58 Work coordinate system #5
G59 Work coordinate system #6
G65 Macro Subroutine call
G70 Bolt Hole Circle
G71 Holt Hole Arc
G72 Bolt holes along an Angle
G73 High Speed Peck Drilling
G74 Reverse Tapping
G80 Turns off all canned cycles
G81 Drilling
G82 Spot Drilling
G83 Peck drilling
G84 Tapping cycle
G90 Calls up an absolute Co-ordinate grid system Positioning
G91 Calls up an incremental Co-ordinate grid system Positioning
G92 Set Work Coordinate system shift value -(grid shift)
G94 Feed per minute mode
G95 Feed per spindle revolution mode
G96 turns on Constant Surface Speed (lathe)
G97 Turns off Constant Surface Speed (lathe)
G98 Canned cycle initial point return
G99 Canned cycle R Plande return

M00 Program stop - Tells the CNC machine to stop in the middle of a program.
M01 Optional Program Stop - Tells the CNC machine to stop ONLY if the optional stop switch is active
M02 Program end
M03 Turns the Spindle on in a Clockwise direction
M04 Turns the Spindle on in a Counter-Clockwise direction
M05 Turns the Spindle off
M06 Tool change
M07 Optional coolant is not available on all machine configurations
M08 Turns flood coolant on
M09 Turns flood coolant off
M10 Normally used to turn 4th Axis brake on (mill)
M11 Normally used to turn 4th Axis brake off (mill)
M19 Spindle Orientation
M30 Program end and reset
M31 Chip conveyor on (forward)
M33 Chip conveyor off
M88 Turns through the spindle coolant on
M89 Turns through the spindle coolant off
M97 Calls up sub program for local program
M98 Sub Program Call
M99 Loop or return to rerun a sub program

More Informative Articles

  • Sheet Metalworking Tools, Supplies & Equipment
  • Metalworking Tools, Equipment & Machinery
  • About Metalworking & Mini Lathes
  • Titanium Tubes, Pipes & Metal Specifications
  • Metal Artwork, Custom Design metal Fabricators
  • How to Solder, De-Solder, Wire Soldering Basics
  • Arc Welding Basics
  • CNC Machine Shop
  • CNC Machining
  • CNC Machining Services
  • CNC Machining Tips
  • CNC Turning
  • Contract Manufacturing
  • Galvanized Steel
  • Machine Shop Tools
  • Outsourced Manufacturing
  • Outsource Manufacturing
  • Production Outsourcing
  • Sheet Metal Forming

    •  
     
    Arc Welding
    Arc welding is a common process in today’s industry. A simplified description of welding would be the melting together of two or more metals through an intense heat process. The result can be a product that equals or surpasses the strength of the original. Welding requires a heat source or power source to create the required heat to fuse the pieces together. Arc welding is one of the most popular forms of welding in use today. An electric arc is used to create the heat required to melt the materials together. This is where the name arc welding comes from. Where two or more materials are placed together to be welded, it is referred to as a joint. An electrode rod is used to move along that joint to create the heat producing arc, and to fill the joint as it is melted. Arc welding basically creates an electrical circuit. The arc welder needs a power source or power supply. The metal you are welding becomes part of the electrical circuit through the grounding cable you attach from the arc welder. The other end of the circuit is completed through the electrode attached to the welder or power supply. The arc is created between the metal and the electrode when the electrode is touched to the metal. Commonly called “striking an arc”. Once the arc is started, the electrode is moved slightly away from the joint. The arc then completes the electrical circuit. Extreme heat is produced. This allows the fusing of metals. In the creation of the arc, an extremely bright light is also produced. This light is dangerous to the naked eye, and so darkened eye protection must be used by all who can directly see the arc. Never look into the arc without proper eye protection. Welding shields or barriers are often used to block out the bright light to protect those in the general area without proper eye protection. When proper safeguards are used, arc welding is a productive, safe method for fusing metal. It is one of the pillars of modern manufacturing. With proper training and practice, one can become a proficient welder who can successfully do general, basic welding.
     
    More Articles...
    << Start < Prev 1 2 3 Next > End >>

    Page 1 of 3