The feed rate does not need to be specified again after a dwell command as the machine still knows that one was defined before the dwell on the G01 block.ĬNC Machines can read measurements in both Imperial and Metric systems (inches and mm) this is defined by G20 and G21.Īlthough it is only needed once in the program it is good practice to add this information after every tool change. The X value in ‘G04 X500’ forces the tool to dwell for 500 milliseconds before moving onto the next block. The few blocks listed above looks like the tool will move 500mm while deep in the part. While drilling with a flat bottom drill and the surface of the bore has a chattered finish, we can stop moving the drill in Z-Axis with it still rotating for half a second to clean up the surface.
#G CODES CNC SIMULATOR CODE#
Sometimes we need to pause the cutter for a brief moment, for that we add a dwell to the code to stop the machine from continuing reading the program for a specified amount of time. These three G Codes are the foundation of G Code programming and are the three you will use when cutting material. When using G02 with G01 and G03 (Counter clockwise arc) any shape can be machined. The K is seldom used but is available if an arc using the Z axis is needed. Using the drawing above, programming an arc using I and J values would look like this: I (X) J(Y) and K(Z) defines the auxiliary axis. The centre point of the arc can also be defined using I, J, and K values. If a feed rate is already active there is no need to add it to this line unless you wish to change the feed rate for the machining of the arc. Using an ‘R’ value to define the radius, the G02/G03 command moves the cutter in a straight line with the defined radius at the end of this move. G02 is used to machine an arc or radius in a clockwise direction and G03 is for anti clockwise. When programming a profile it is easier to use cutter compensation G41 and G42 then you do not need to allow for the radius of the cutter when plotting your tool paths, you can simply use the dimensions on the drawing and the machine will offset the cutter to achieve the correct dimensions. It is not common to cut with the Z axis as well as X and Y but it is possible if needed. This command can be used with all axis cutting at the same time, or just one. In much the same way, a feed rate (F50) is only needed once until you want to change the speed in which you are cutting. You don’t need to add this command on every line, as long as there is no other movement G-Code active, for example, you only need to add it after a G02, G03 or a G00 command. This command has to have a feed rate (F) active before it will run.Ī typical block would look like G01 X-100 F50.0 The G00 command can be shortened to G0 as the older machines didn’t have much RAM and every bit counts.Ī G01 command is used when you are cutting in a straight line. It will increase your machining time by a second or two but it will help avoid a 3 Axis crash. If you are unsure it may be wise to move the X and Y axis first, then on a separate line, move down in Z. When using a rapid move, be aware of any clamps, vices, and parts that may be in your path. The top speed is set by the machine parameters and therefore is only controllable by the operator using a rapid override control. It is used when the cutter or tool is not removing material so that the time it takes to machine the part is as quick as can be. G00 is the rapid travel command in G Code. In the example above I am moving the cutter 100mm to the left. It is in this mode you will do the most damage if you didn’t get your tool set up right. Keep your hand on the feed knob and come in slow for the first time run. Some machinists like to rapid as close to the part as possible but I advise giving yourself at least 1mm clearance. This command is used when the tool is not touching the part to rapid move, normally used when going home for a tool change and returning with a new tool. It can be shortened to G0 as the older machines didn’t have much RAM and every bit counts.