The Advantage and Disadvantage of Roland CNC Machine

The lab is equipped with several different CNC mills. To help you choose the right machine for your needs, it lists the advantages and disadvantages of the Roland machines. PRL currently has three 2-axis CNC mills and three 3-axis CNC mills. All of these machines require code to be generated from a CAM program (Virtual Gibbs or Surf cam) and CAD (Vellum, AutoCAD or Solid Works) drawing. You can program at the machine consoles, although this is impractical for complex shapes. Some of the machines have “canned cycles” or preprogrammed shapes such as circles, ellipses, etc. that are very simple to program at the console.

Roland
The Roland Camm-3 Mini Mill is a full 3-axis portable mill. It is very simple and quick to learn.

Advantages•Spindle speed up to 10,000 rpm, accurate to within +-.01mm. Very simple, easy and quick to learn.
•Sees very little student use, so it is easy to secure time on the Roland

Disadvantages
•Only plastics may be machined on the Roland.
•Only holds one tool. To use separate tools you must send separate programs. Always runs DNC - it has no brains onboard.
•The Roland is metric, so finding specific end mills can be problematic. Small bed for machining ( roughly 7x20” ).

»»  CNC PROGRAMMING...“The Advantage and Disadvantage of Roland CNC Machine”

G-Codes Come from CAM Program

G-Code programming is a simple language and very robust. G-codes are what CNC Machines run on. A CNC control program processing the G-code line by line and send this information to the machine. Then the machine takes this information and makes precise movements.

The G-Code comes from the CAM program. When you process your design in your CAM program you pick out various machining parameters and inputs. You match it up with the CNC Machine the part will be run on and then Post-Process. Then you CAM program spits out very precise G-Code for your machine and your part. You will need to go through the CAM process again if you make changes to your design.

• Post Processors 

A post processor is a way of specifically you CAM Program will process the design. There are standard and custom ones. If a standard one doesn’t work, most good CAM Software gives the option to customize the post processor to fit the needs.

• Canned Cycles

There are G-Codes that do pertain to Canned Cycles. The Canned Cycles is targeted toward beginner to intermediate CNC Learners.

• The Big G-Code List

What comes next is a listing of what each g-code means. You will need to be familiar with your own CNC Control Software, CAM Program, and CNC Machine to determine if they have changed something. 

»»  CNC PROGRAMMING...“G-Codes Come from CAM Program”

The Future of G-Code and M-Codes

The Future of G-Code and M-Codes
The G-code future is in jeopardy. There are changes to try to create a new standard. The new standard where you can go straight from CAM or CAD right to the CNC machine.

Basically this is an attempt to try to eliminate a step in the CNC Process. Others have tried to eliminate or update G-code before. Its simplicity has won out, so far.  It has survived.
 
What are M-Codes?

M-Codes are other codes that are throughout in the CNC Program. Think of them like the lesser cousin of G-Codes. M-Codes are generally very specific to the machine. For instance, “M03” might stand for “Torch Off” on a CNC Plasma Cutter. It also stands for “Spindle Turn Clockwise” on a CNC Mill or CNC Router.

M-Codes

• M0 - program stop
• M1 - optional program stop
• M2 - program end
• M3 - turn spindle clockwise
• M4 - turn spindle counterclockwise
• M5 - stop spindle turning
• M6 - tool change
• M7 - mist coolant on
• M8 - flood coolant on
• M9 - mist and flood coolant off
• M26 - enable automatic b-axis lamping
• M27 - disable automatic b-axis clamping
• M30 - program end, pallet shuttle, and reset
• M48 - enable speed and feed overrides
• M49 - disable speed and feed overrides
• M60 - pallet shuttle and program stop

»»  CNC PROGRAMMING...“The Future of G-Code and M-Codes”

CNC System of Input Device

One of a CNC system is Input Device, they including: 

• Floppy Disk Drive

Floppy disk is a small magnetic storage device for CNC data input. It has been the most common storage media up to the 1970s, in terms of data transfer reliability, speed, storage size, data handling and the ability to read and write.

• USB Flash Drive

A USB flash drive is a rewritable and removable portable hard drive with compact size and bigger storage size than a floppy disk. Data stored inside the flash drive are impervious to dust and scratches that enable flash drives to transfer data from place to place. In current years, all computers support USB flash drives to write and read data that make it become more and more popular in CNC machine control unit.

•  Serial communication

The  data  transfer  between  a  computer  and  a  CNC  machine  tool  is  often accomplished through a serial communication port.   International standards for serial communications are established so that information can be exchanged in an orderly way. The most common interface between computers and CNC machine tools is referred to the EIA Standard RS-232.

• Ethernet communication

Due to the computer technology advancement and the drastic reduction of the cost of the computer, it is becoming more practical and economic to transfer part   programs   between computers and CNC machines via an Ethernet communication cable.

• Conversational Programming

Part program can be input to the controller via the keyboard.  Built-in intelligent software inside the controller enables the operator to enter the required data step by step.

»»  CNC PROGRAMMING...“CNC System of Input Device”

Instruction Types of CNC

Instruction Types of CNC

 A line of G-code file can instruct the machine tool to do one of below instrctions.

• Movements

The basic motion for a controller is to move the tool along a linear path from one point to another. Some machine tools can only do this in XY, and have to accept changes in Z separately. Some have two further axes rotation to control the orientation of the cutter, and can move them simultaneously with the XYZ motion. Currently 4 and 5 axis machines have become popular. The 2 additional axis allow for the work surface or medium to be rotated around X and Y. For instance, a 4-axis machine can move the head of tool in XY and Z directions, and also rotate the medium around the X or Y axis, similar to a lathe. This is called the A or B axis in most cases.

• Drilling

A tool can be used to drill holes by pecking to the swarf out. It can be used to cut screw threads using an internal thread cutting tool and the ability to control the exact rotational position of the tool with the depth of cut.

• Drilling cycles

A drilling cycle is used to repeat tapping operations or drilling on a workpiece. The drilling cycle accepts the parameters list of about the operation, such as feed rate and depth.

•  Parametric programming

A recent advancement in CNC interpreters is support the logical commands, known as parametric programming. Parametric programs incorporate on both these logical and G-code constructs to create a syntax and programming language similar to BASIC.

»»  CNC PROGRAMMING...“Instruction Types of CNC”

Learning CNC with CNC Machining Center or Turning Center

Almost all CNC using companies have at least one turning center or machining center. If you are not versed fully with its usage, it’s likely that you’re not taking full advantage of what these sophisticated machines can do. These two courses teach CNC machining center and turning center usage from the ground up using the proven key concepts approach.

The CNC principles are best introduced and learned during discussions of manual programming (also called G code programming). Concepts like program zero assignment, compensation, motion types, and special features are easy to master at G code level. Yet many CNC people that use CAM (computer aided manufacturing) systems avoid G code level programming like the plague. Or worse, they have never been exposed to it. All CNC people should have a good working knowledge of G code - especially if program changes must be made during a program’s verification regardless of how you develop programs. It produces is like using a calculator without understanding basic arithmetic using a CAM system without understanding the G code level programs! It is the chance to get up to speed!

While the key concepts can be applied to any CNC turning center or machining center, all specific examples are given in the format for the Fanuc control, the industry standard for CNC. Fanuc is so popular that many control manufacturers claim to be Fanuc-compatible including Haas, Yasnac, Mitsubishi, and Hitachi.

»»  CNC PROGRAMMING...“Learning CNC with CNC Machining Center or Turning Center”

The History of CNC Development

The History of CNC Development

The CNC is call for computer numerical control and it is refer to a computer “controller” which specifically drives a machine tool and reads G-code instructions, typically a powered mechanical device used to fabricate components by the selective removal of material. CNC does numerically directed a cutting tool interpolation in the work envelope of a machine. The CNC operating parameters can be altered via software load program.

CNC was preceded by Numerically Controlled (NC) machines, which were hard wired and their operating parameters could not be changed. NC was developed in the late 1940s and early 1950s by John T. Parsons collaboration with the MIT Servomechanisms Laboratory. The first CNC systems used hardware of NC style, and the computer was used for the tool compensation calculations and sometimes for editing.

Punched tape was continued to be used as a medium for transferring G-codes into the controller for many decades after 1950, until it was eventually superseded by floppy disks, RS232 cables, and now is commonly tied directly into plant networks. The G-codes files to be interpreted by the controller are usually saved under the .NC extension. Most shops have their own saving format that matches their requirements of ISO certification.

The CNC machines introduction radically changed the manufacturing industry. Curves are as easy to cut as straight lines, complex 3-D structures are relatively easy to produce, and the number of machining steps that required human action has been reduced dramatically.

»»  CNC PROGRAMMING...“The History of CNC Development”