CNC milling machine cycles | G-Code Tutor | Skillshare

CNC milling machine cycles

G-Code Tutor, Engineering Artist

CNC milling machine cycles

G-Code Tutor, Engineering Artist

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7 Lessons (34m)
    • 1. Intro

    • 2. G81 Drilling Cycle using G98 and G99

    • 3. G82 counter bore cycle

    • 4. G83 peck Drilling Cycle

    • 5. G84 Tapping Cycle

    • 6. G85 bore cycle

    • 7. Helical milling

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About This Class

Having a full understanding of the canned cycles used when programming a CNC mill is an important skill for a machinist.

With this knowledge you will be able to use a lot less code in your program saving time to produce the parts.

Learning canned cycles is not hard, they are mostly the same with a few differences depending on what the cycle does. 

This course will bring you up to speed on programming your CNC router or milling machine with these canned cycles.

Meet Your Teacher

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G-Code Tutor

Engineering Artist


Hello, I'm Marc.

I have studied engineering and portrait art for over 26 years. A strange mixture indeed.

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1. Intro: Hi, My name's Mark. Welcome to Chico Cheetah in this series of lessons against teach you how to program a CNC milling machine using a panic decode. Once we've covered the basics and then move on teaching about different cycles, we use a G 81 journey. It cycles G 83 penetrating cycles happened and even boring a large diamond hole. We also make apart so you can see how these things work. Railroad environment. In this course I cover how to program a CNC machine from all the sides was available to us to heli coil 1,000,000 program in different parts and shapes and profiles. Harry Geico, Cheetah teach how to program CNC machines So it's easy to follow and quick to understand. 2. G81 Drilling Cycle using G98 and G99: in this lesson, I will go over the basics drilling cycle T 81 on different variants of it using G 98 G 99 g coats. Let's have a look how this works. This operation can. She's a full 0.2 millimeter drill. I couldn't be bothered to draw to flick drill, so we're gonna use the force lead to my drawing. We've already written the 1st 5 lines of code when we done our parts program. So refer back flat for what's each meaning does of the geek AIDS and to the G 10 etcetera. But for now, since we're concentrating on the G 800 in cycle, we're gonna go ahead to where we start activating the cycle d 00 x 2020 takes us to the position of our first hole using the rapid movement. As with our parts profile program, we'll bring the sit down on a separate line on activate the M 08 to turn on coolant. Here we have RG 81 line G 81 tells machine we used in the drilling cycle. This is just a standard driving cycle and not a peccadillo in cycle. I will cover the package rolling cycle in a different lesson. Machining of material is 10 millimeters thick, so I'm taking a drill to two millimeters past the bottom of the material, but used instead of minus 12 on our debt. This sets the debt for each hole as it's drilled. ER one point notes is our attracts value. This is the distance above the surface of the material that the Drover tracks to after each hole. This assumes that her date a musician zero on the surface of the material and finish off. We had a feet right. In this case of used 50 millimeters per minute to draw, the next hole or we need to do is give the distance from the first hole to the second hole and the axes. So this hole is 50 millimeters to the right, so we just add X 50. The machine automatically drills a hole to the death of 12 millimeters retracts one millimeter above the surface, using the feed rate of 50 millimeters per minute as we defined on the GI 81 line, same as the previous whole. The distance and exits 50 millimeters between the next two holes. So as an X 50 moves little incrementally. We don't need to set the machine into incremental Moz do this. All drilling cycles work incrementally the distance to our final hole. It's 40 millimeters along the Y axis. So why 40 Joe's our fourth hole? To cancel a Jordan cycle? Or in fact, any cycle that's active. We use G 80 se GI 80 cancels all cycles interactive. Well, it's left for us. To do now is take the cutter home back, so it'll change position. But first I looks rapid the cutter away to said 50. So it's nice and clear away from the components and any clamps. And No. Nine turns are couldnt off. Using G 50 free tells machine that we know wish. Use our machine datum so X Y and Zed zero takes a machine back to the machines zero points M 05 stops to cut her from rotating, and we finish this section of the program off with M 01 optional. Stop commands say that's what a basic G 81 joining cycle looks like. Now what about Jean 98 G 99 on what I Well, when we're moving between holes, it's best to keep a minimum of rapid distance off the top off the material. This is to make the program running as fast as possible. But if we come across a clamp, occasionally need to lift a little further up to avoid the clamp. Let's have a look at a program that we used the 98 denotes known for so I can show you how this works. Mommy at a gene 99 to RG 81 line them tool retracts to our value in this case, one millimeter about the surface of the material. If we don't insert a gene 99 here, it was still retract to our 1.0. If we don't add the are 1.0. Most machines were attracted to the 15 millimeters of the head movement above that line. So why, after G 99 in the first place? Well, discuss subsidy option to also add a G 98 line within the program. So we hop over clamps. Let's read through the program so we can see how that works. Dimensionally. It does work the same Mr G 81 as we've just done on X 50 Incremental move takes us to the second hole on automatically drills it. But with this clamp in place, if we continue to wrap it to our photo whole one millimeter above the face of material, it's not gonna end well. So by as Energy 98 to list line, we can tell the machine that we wish to rapid to our original rapid position of said. 15 are not the position defined by the are one. So G 98 in this case tells a machine to live to cutter up 15 millimeters above the face of the material when we traveled to our final hole. We don't have this restriction has there's no clamps in place so we can use a gene 99 command again to tell The machines used the original rapid distance of one millimeter above the face of the material that we defined on the G A. T. One line of the our value. Then that's before G 80 cancels are drilling cycle, and the rest of program you're already familiar with a top down view is probably not the best way to visualize this. So here's the same thing again. From a side view. We move our toll into position with the G 00 rapid command and follow lights with a rapid movement down to a safe working distance above the material and the clamps would said. 15. Move Reactivate RG 81 Drilling cycle With the Gene 99 code in place on Drew our first hole , our drill retracts to one millimeter above the face of the material or one millimeter above zero, said the point that we set with the Datum. Note. The machine is in gene 99 mode, so it is using the R value. At this point, X 50,000 machines moves to drill 50 millimeters in the X Plus direction where automatically drills a hole. Now the fan it control sometimes read a line in front, as it does in this case, it looks ahead and sees the gene 98 fairly on the following line. So when the drill retracts every tracks, Baxter said, 15 position are not that are one position. It also sets a machine in the G 98 mode until we states otherwise of a gene 99 commands as the Gene 98 commanders on this line, it's safely hops over the clam and drills the next hole for our final hole. There is no clamps in the way so we can use Gene 99 again to tell the machine that we only wish to retract by one millimeter, but to face the components and not 15. So here, G 99 tells machines. Refer back to the R one value on the GI 81 line on only retract one millimeter between this hole on the last hole, it is important to note that a G 98 Jean 99 commands go on the position off the whole. After we wish the hop toe happen, and that's before we finish off our cycle. VG 80 commands that cancels the drilling cycle. So in this lesson, not only did we learn what the G 81 drilling SoCo is and how it works, but also the Gene 98 Jean 99 commands to avoid clamps or other obstacles in the machine while we're using a German cycle 3. G82 counter bore cycle: say the GT two countable cycle. What is it? How does it work? Let's have a look. Believe it or not, RG code for accountable cycle is G 82. The X and Y position or units are optional, but we can Adam Tillis lines teller machine the position of the first hole that we wished accountable. The set defines the depth of accountable. This is taken from the machine datum zero, which is usually the face of the components. Our is our retract fuddy the same SG 81. This is a distance the drill retracts to from the surface of material after each drilled hole. Here's RPI value. This is a time that the drill dwells in the bottom of the bowl. It is this value that makes this different from the usual G 81 German cycle. Because of GI 81 Julian Cycle doesn't allow for a dwell at the bottom of the drilled hole. Women counter boring or counter sinking, it's usually avoidable. TWI did well to increase surface finish on dimensional accuracy and, as usual, F defines our feet rates. Here is a quick example off how this looks within the program on the can cycle line. We had a G 80 to tell a machine that would use an accountable cycle with a Dwell said. Minus 12 millimeters defines our depth of each hole that we wish to drill. Ours are retracts valley the distance that a drill with tracks between each countable. This distance is taken from the surface of material in the plus direction. This value is what makes this a G 82 not a G 81. This is our dwell value. The value is in milliseconds, so 500 milliseconds will be half a second that the drilled wells for the bottom accountable before rapids away. Tr one value and, as usual, F is our feed right to command. We can also add to the GE 98 G 99 commands to hop over any clamps to retract the drill fervor if we need to. The same is 80 81. Cycle here have inserted the Gene 98 G 99 G codes in the correct place. To avoid this clamp on the drawing 4. G83 peck Drilling Cycle: so we've covered it. Stand. It's drilling cycle. Let's have an in depth look of how a pectoral in cycle works. Using GI 80 Free Command the standard phonic decode For a peck training cycle, it's usually key 80 free. It's can change depending on the different hopes of control. Juice Machine has using the Fan X standard. This is normally the G code that we use, adding the X and Y coordinates on the T 80 free line is optional. The way I normally program is, I moved to cut into position. Usually Geo Command a few lines above the G 80 free line. By using this technique, I don't need to add to the X and Y positions because it's cold is already in position. But we can use X and Y coordinates on RG 80 free line to define the position off the first hole. Assuming we have set the date among the surface of material, our deadline on this move defines the death of our whole after each pack of the drill, the drill with times to the same position. We define this position by using our value. This is not retract value. If we are drilling into a blind hole. In other words, our whole doesn't go right the way through the component. Weaken added. Well, value. This is sort of drill stops at the bottom of the hole for a few seconds that we define with a P value. This is used to clean up the bottom of the whole and also has to greater dimensional accuracy, which allows us to have greater repeatability on the holes, said a debt remains more constant. The Q value in this case, the finds the death of each pec. This is the amount of material to draw will remove on each pec before it rapids back to the opposition. And finally, we have our feet right. This is usually defined in millimeters per minute. Say, what does this look like inside a program? My Let's have a look. You're really familiar with our part on already familiar when we drilled out holes so we can keep the program pretty much the same and just changed the G 81 line to the T 80 free line to demonstrate. So let's have a real world. Look at how the pecking cycle works. G 80 free defines are packin cycle. It's very similar to the G 81 cycle. As you'll see in a second I said Dimension to find the death we wish to drill to go on each pack. In this case, there's still 12 millimeters. As I'm assuming the bill, it is 10 millimeters thick and I wish to drill to come out the other side of Bill. It's about two millimeters. Our value defines our retract value. This is a distance to drill retracts to after each pec. A value of our one millimeter brings a tool a millimeter about the surface like material after each pick a P value housing machine. How long to dwell on the bottom of the hole so we can clean up the surface in some control systems, especially the new ones. This is defined in milliseconds say a value of P. 1000 milliseconds is equal to one seconds. This may also be shown as P 1.0 on some controls. The key value Now the key value defines the death of each pec. So each time to drill pecks, it will move free millimeters until the hole is complete and finally we have our feet right 50 millimeters per minute is just for demonstration purposes. This would change greatly depends on what material you're cutting. So what happens if we have a clamp in the way? And we wish to occasionally retracts her drill over, then the R one value of one millimeter? Well, it's the same. Atsugi 81 cycle on bilateral mean we can add a gene 99 a gene 98 command in the program to retract our drill favor to avoid any obstacles. This is the same as we discussed when I was explaining the G 81 drilling cycle. So the operation of a G 80 free Pecker Julian cycle is very similar to the G 81 cycle. Apart from the fact we can have a Q value toe, add a peck depth on each drilled hole. A pack in Joe Cycle would usually be used when you're drilling a deep hole or when you're cutting hard materials. It is also known as a chip breaking cycle to break this wolf up to stop the drill, getting overloaded with swore on breaking 5. G84 Tapping Cycle: So we've drilled are holes Now we're gonna have a look at tapping them. We can tap them much. Same way using a cam cycle as we did when we drilled them. So if list we're gonna use a G 84 can cycle similar to the L A. Can cycles we used for drilling, we have the option of that in the next time we coordinate here. This is a position off our first. How that we wish to tap. They said Folly defines how we wish our threat to go Bear in mind. Most taps have a small lead in on the front of the tap. This has to be allowed for when we're deciding how deep we want tap to go into the material . The our valiant is retracts value. How far we wish it's happened to remove from the material before we rapid to our next hole . Ah, the key value is an interesting one. With the key value, we can pick tap. It's always looks very impressive, but before we compact up, we have to change the G code G 84.2. This allows us to be out pick without tap. This means that tap will cut, afraid to a certain point, then reversed out of material and then keep repeating the process until the full length afraid is complete. This is great for clearing out swore from stopping holes where tap keeps breaking, so the key value it's the distance of each pec. The F value is not a feed rate. In this case. We use it to define the pitch off the Fred that we wish to cut for this operation. I'm going to use an M five tap to machine a metric course, Fred in our 4.2 millimeter holes. So the pitch for this is not a 0.8 millimeters. This is what we set our F value to. Now we're going to have a look at how we use the T 84 rigid tappin cycle within the program . The first thing we need to do is tell the machine that we're not using the feed rate off millimeters per minute. Since F no equals pitch are not feed rate. We need to tell the machine that we're using millimeters per revolution on not millimeters per minute. We do this by adding a gene 95 in the program on some machines and control systems. This is not needed to have this gene 95 but it doesn't do any harm to do it anyway. As a safety precaution. It's a gene 95. It's a G code. That's house machine. We're going to be using the feet per revolution off the spindle. Jean 94 puts a machine back into millimeters per minutes mode before the end of this happen sequence. I like to switch back to the GE 94 millimeters per minutes mode. This is so this block and run on its own. And if we have to put back in the program and reach up, these holes, machine will be in the rights modes. Next time we do, it'll change. So let's have a look. It's blocked for Kate. G. 84 has a Richard tapping cycle, Mode said minus 12 millimeters is a depth. We wish startup to machine, too. Taking our billets has 10 millimeters thick. We're going to millimeters past the outside of material. Several tapping for if the components are five point note is our tracks value. This brings the tap five millimeters above the face of the components after each tap hole. And finally f not 0.8 is got to be the same as the pitch of the phrase that we're cutting now, setting our attracts value of five millimeters. It's all good for cycle times, but what happens if we come across our clamp again by the G 98 Energy 99? Values still work we're doing attacking cycle. So if we need a hot back up a little bit higher for original Rapid, limped off said 15 millimeters. We can do this by using a G 98 orgy 99 command for more information on the use of these G codes. Affair back toe RG 81 Drilling cycle lesson. So if the whole we're tapping is a deep hole, or if we use the soft material such as aluminium that keeps clogging up the tap and breaking it, we can use a peck tappin cycle. We're using a G 84.2 instead of a G 84. This allows us to use a Q value so we can set the peck that, by setting are picking that free millimeters. The machine will cut free millimeters threat reverses, spindle and come back up toe to find our value in our case is five millimeters above the surface of material. Then wrap it back down just before the Fred and start cuts in the next free millimeters a threat. They will repeat this until the full length afraid has been cut. So far in this lesson, we've covered cutting a rights hand. Third, what happens if we need to cut a left hand? Well, for that, we use Geico to G 74. Every think house remains exactly the same as I have talked on. This lesson in this section are covered all the ways we can tap a hole on a CNC milling machine or a CNC router. 6. G85 bore cycle: safe are in a cycle section. We've learned how to drill holes. We've learned how to pectoral holes, and we've also lent how to tap holes. Now we're gonna have a look at boring holes. The G code we use for boring is G 85. We can also use G 86 which will cover nearly ended this lesson. It's pretty much the same the way it works. So we just go over G 85 for now on our Shaler differences later, the same as the other cycles we've discussed. The X and Y coordinates positions are totally optional. If a machine is already above the hole that we wish to bore, we don't need to add to these lines. But if we have not fused G 00 to rapid to the position of the first hole, we can add our corners here on the machine. Remove ready to bowl. In position Is that the mentioned controls? How deep we wish our boat to go. This is a distance from the data position to the bottom of the ball instead. Same as the other cycles are defines our retract position. This is the distance above the data position that we wish to retract to after each heart we bought and F defines our feed rates, which is in millimeters per minute. I'm now going to go ahead and show you how this works inside a program the G coated G 85,000 machine that we're going to be using a boring cycle that feeds in and feeds outs off the ball, said minus eight millimeters is our debt that we wish to bore, too. Why are 1.0 is one millimeter above the surface? It's our tracks value, and finally, a feed rate of 30 millimeters per minute is defined. We're not restricted to board the same depth on each hole. We can change the debt if we wish to bore by adding it's edified you here. This works the same for the other cycles as well. The drilling, so called apex cycle and also the Tappan Psycho, adding G 98 Jean 99 also works during the boring cycles, so we can still jump over our clamp with a boring bar in much the same way as we did with the drills and drill in cycles that we used now G 85 is not the only boring cycle available to us. We also have G 86 now. The only difference between the two circles is using GI 86 stops. The boring bar at the bottom of the bore them rapids out SG 85 balls in on bulls out. Sometimes we may not wish to bore out as it may affect the finish your dimensions. So having two different decodes gives us the option. So it stopped the spindle at the bottom of the ball on rapid out, and that concludes our lesson on boring on a CNC milling machine. 7. Helical milling: in this lesson against covered, scary topic of Healy Co. Inch appellation. It's often a much misunderstood subject, and it's not as difficult as it seems when it's broken down, step by step, which is exactly what I'm going to do now. But first, let's have a look at the different things that it could be useful generating holes. Sometimes we need to produce a large hole bigger than we wish to use a drill for, or maybe a flat bottom hole. The easiest waste delis would be to generate its with the milling cutter Raveling using the drill. And that's what this parcel courses about. I'm going to show you how to generate a hole using helical interpellation. We can also use it for secular ramping. This is where we cut down to depth to machine of features such as a pocket or a slot. We can even use it to start off cutting the profile to bring the cutter down to death. And finally, my favorite Fred Milling. This is where we can cut a threat by milling down in a spiral using a Fred meal. This is great for producing friends in very hard material, such as titanium. So what exactly is Hilly cow interpretation? Let's have a look. Using a milling cutter, we can make a pocket like the one shown in this diagram by cutting in a radial move but also in his debt access at the same time. So we're using G 02 or G I three, most also coming down in set in a spiral shape. It's also explains why it's often called spiral milling to ensure we don't leave a pip or a race part in the bottom of the flat hole. We need to use a cutter that is larger than the radius of the whole, as shown here. Now let's have a look how we can use hilly corn tabulation two mil a 60 millimeter bore inside of components as a way to make the program easy to follow and clear. To understand, I've chosen to put the data position where we wrap it in our milling cutter. This makes the code look a lot cleaner and easier to follow. So you're not just reading a bunch of numbers are not understanding what everything does, since we're going to be machining a 60 millimeter bore, I'm going to be using a 40 millimeter milling cutter for this operation. That way, we don't leave a pip in the middle of the blinds whole because the milling cutter is over half decides of the diameter of the ball. It's larger than the radius. The CO two T 06 detonates Our tool number were using to six. The following digits 06 is our offset number. It's a T 06062 or six offset six on an operator's noting brackets that tells the operator which cutter to load into the spindle for this operation m 06 its automated tool change codes. This tells machines pulled it all number six from the carousel. I load this into spindle. I've added a few more G costar safety line slits come over them. The G 90 tells a machine we're using. Absolute measuring system are not incremental, do you? 54 is our datum. This calls information from the machine controls into the program to tell it's what datum were using and where it is. G 21 tells machine we're using a metric system. G 17 defines the plane that we're working on. G 80 cancels any cycles that may be active if we stop the machine halfway through a section of program where it's a psychoactive. This will cancel it when it reads this line. And finally G 40 free, which is our cutter compensation. Calling upon a G 40 free of no offsets tells machine to look into a tool table and poorly offsets from the tour table from offsets 626 Yes, value defines our spindle speed, and M o free tends to cut around in a clockwise direction. Now we records to our start point or a data position, which has explained just now offset X zero y zero at the start of what we wish to cut just to make the program cleaner to read on a separate line a rapid the cutter down to said one millimeter that brings it to one millimeter off the surface of the material M 08 turns on our students. At this point, you will know if you set your tool correctly cause rapid in one millimeter off the face of material. Both ends well, if you haven't switching over to a geo one feed rate command and that bring the cutter down toe north 2.1 millimeters off the face of material, using the feed rate of 200 millimeters per minute. Now we can start cutting in a spiral fashion A G A free 1000 machines start cut in an anti clockwise direction. Why stop? X movement is the end of knock, which is the opposite side of the ball. We keep boy zero because we don't wish to change that. We're coming down and said two millimeters during his procedure of a radius of 30 millimeters to cut a diameter off 60 millimeters. I've not had a feed rate as it's still active from the line above. But if you wish to use a different feed rates while we're so cliched relation let less we can do. We now move to cut back to X zero y zero. The beginning of our circle instead of minus four millimeters, takes a two millimeter cuts during a semi circle. The radius remains the same throughout. Now we have machines, our first complete spiral in a circle. We now just repeat the same blocks of code by bringing it down instead, each time by two millimeters. If I set a datum in a different position we wouldn't be seeing simple numbers to read like X 60 y zero. This is what I've done this purely for clarity for the demonstration purposes of this video , I am willing. This circle pockets 10 millimeters deep, So in this line it takes us to our final death of 10 millimeters without index and down instead anymore. I'm now taken. One are circular passed to clean up the bottom face off the board. We can also increase the radius here to clean up the cycles. But that would mean cutting the rest of the boar undersides slightly. On this block. We complete our final circular motion as I rapid out Hubble. I do so at an angle. Bring it into said 30 brings a cutter into the center of our bull as we come out. This is because I don't wish to cut her to touch the side of the bottom off the ball when its way out the job. No, that's We are free from the components I can wrap with way instead safely. This is also a good time to turn off the Kudrin's flat. We use em over nine. One way to tell the machine to go back to its reference position is by using G 50 free the machine datum. We can also use T 28 to get the machine to go back to its reference points. I m. A five stops the cutter G 40 turns off our cutter compensation and finally m 01 This is our meme code for options. Stop after your proto wishes. He can push a button on the controls and have the machine stopped at this point. So we commissioned a bore to make sure it's correct. And that is how we use here. The coil interpretation on the Miller machine, as many uses it's wealth experiment and we've been practicing with. It's a handy technique to know, and you will find you use it quite a lot when programming seen similar machines.