Precision machining takes more than clicking on some buttons: Surprise? In the summer, I run a CNC factory (tabletop MDX-40 by Roland) Create prototypes and test beds for medical devices. This is a real trial. and-error, learn-as-you- I \'ve been experiencing go since my mentor took a vacation, so I \'ve overcome my steep learning curve, and I \'ve attended a marathon meeting in addition to learning not to do anything. e. Destroy small pieces and check each situation for the nuggets of wisdom ( What are the benefits of mistakes? ). I keep a comprehensive notebook on all this knowledge, so when I type for my long time The term is used, and I decided to turn them into Instructure for others as well. In precision machining, I learned that it is important to consider different manufacturing processes ( Burrs in extrusion direction) , Fluctuating clamp readings, aligned pins for flipping, and more. I will also share quick tips on saving time without compromising the cutting accuracy of your work. This instructable assumes that you have never done CNC milling before, but in most cases it does not discuss how to process ( Because there are already great tutorials) : Just share tips and tricks to achieve better precision cutting. Warning: this is a very intensive tutorial with lots of text, but I just want to include as many details as possible to make things clear. The title of each step should be fairly descriptive, so you can easily choose to skip some steps if you want. I also try to boldly highlight key details so that they stand out when you browse. These suggestions are not rules that are absolutely to be followed: they are just suggestions that I find helpful. Not all factories are equal, but these techniques are sufficient for most processing jobs. Please comment on other suggestions you have come across: I am always willing to learn more! Milling is a subtraction manufacturing process in which you start with a solid block of your stock material and then cut it off to show the object you ultimately want. CNC represents computer CNC, CNC milling defines the computer together- A controlled approach in which you can model an object using specialized software and send it to a machine that cuts materials according to an automated toolpath. Milling uses a \"blade\" similar to the drill bit, but milling uses end milling when the drill bit is used. These are different from drilling, where the drill bit moves up and down the axis of the rotating tool, but when milling, the end mill advances perpendicular to the axis of the rotating tool ( So the cutting mainly occurs at the circumference and bottom of the vertical mill). There are many flavors in these terminal factories, which will be explained in step 11, or these links here and here ( Second, there are many technical details. Great resource too. In order to handle different processing work, there are many different flavors throughout the factory. For example, the desktop I use is smaller (image above) But there are industries. Huge behemoth Different shaft systems also exist: the support translation system I use in 3 axes, so the end mill can move up and down on the Z axis or horizontally on the XY plane. Additional axis reference rotary axis: for example, the 5-axis milling machine can move in XYZ direction in addition to the two rotary axes, so that the vertical mill can approach the material block from almost any direction. This is especially helpful for achieving a better surface finish as the tool can move vertically on the surface. The bare- Skeleton workflow for milling: additional stock material ( Depending on the power of your factory, it is possible to go from soft polypropylene to stainless steel or above) Use tape or pin to cut the work table/work table of the mill, use the mill to cut out the geometry you want and carefully remove the finished product. The next steps will guide you through these generic processing steps and complete post-processing Processing of metal parts. In order to obtain a perfectly defined geometry from machining, it is important to first have a perfectly defined 3D model. For example, there is something called string tolerance, because approximate circles are simulated with a large number of line segments instead of actual curves. This page here is a great resource for this issue. Commonly- Common software includes Inventor, Autodesk Fusion 360, Creo, SolidWorks, and Blender. Once you have the perfect ( Or at least as perfect as you need) Model, which is usually used as an export. stl or . Obj or similar software, interface between your design and milling machine. The specific driver depends on your specific factory, but for the one I use, it\'s called Modela Player 4. Here are the links to how this software works quickly ( Similar program)works. When you set the sacrifice block of the factory ( The material you put on the stage, if you cut it too deep, you can destroy it well) On the workbench, try to minimize the vibration in the system using a heavy plate/block. For example, MDX- 40 I am using some hard plastic plates, but in order to increase the quality and thus minimize the vibration, we replaced it with aluminum blocks. This may interfere too much. Cutting, which means you cut deeper to make sure you cut out the bottom completely so you don\'t have to worry about cutting and archiving the original edges later. For over- Cut, you want-be- The processed material is the same as your sacrificial block material, so since we use aluminum, it\'s not good if we cut acrylic. So we also put an acrylic block on the top as the final sacrifice block: Aluminum still minimizes vibration, but acrylic is the ultimate sacrifice material. If your software provides a preview of your programmed cutouts, it\'s always a good idea to check them to see the estimates for your final product! For the Roland Mill I use, the Modela Player 4 software provides a preview of what you see in the blue image above. Just upload yours. Stl, program the cut you plan, and see how it turns out so you can redesign your model when needed. In the first picture of the Star Trek icon, I selected a ball mill for rough machining in this particular cut, so you can see the raised grooves left by the back end. Even if one step is done at the ball end, these stripes will remain on a flat surface, so be sure to finish the flat surface with a square vertical mill. In the corner, you can also see that there is a slight rounded corner instead of the completely sharp corner that the Star Trek badge should have. This is because the radius of the end mill is limited and the inner angle cannot be completely solved ( Good outside corner-- See the sixth picture above). The sharp vertical inner angle shown in the sixth picture above cannot be completely solved, because the end mills will have some limited radius no matter how small ( 1/32 \"end mills will make beautiful corners but still not completely sharp). If you have a pocket designed to fit like this, you have to round the corners of this pocket cut and the edges of the parts in the fit ( Also, make the fillet of the pocket a little smaller (~0. 05mm)to oversize it-- Because smaller rounded corners mean longer lines. - And help integrate the work into it). If your software doesn\'t have a preview option, you can add rounded corners with a potential Vertical Grinding radius to your model to see the estimate. Sometimes it\'s a good idea to expand your project if you can save material and still fit the purpose of your work. See the second and third picture above: The second picture has a larger vertical mill cutting design, so the valor Pokemon design is not fully defined, but 1 is required. 5 hours. The third picture uses a smaller vertical mill to complete more finer details, but it takes about 3 hours- You can see this deal. Rest between getting more details about the price of longer factory hours ( Will wear your vertical mill faster). If you expand your design, larger end plants can get in and out more details faster ( It\'s a bit controversial, but you can know which side I\'m on). The fourth picture shows some of the processing marks left on the material. It shows the difference between the square and the ball mill, and something else: click on the picture and read the notes for more information (pretty long). The fifth picture also points out an anomaly that you might see: there will be strange marks on the edge of the material when the surface is treated. When you have aligned locating pin holes in your model so that it perfectly fits and aligns to another machined workpiece, you want important features to be milled on the same surface as the aligned holes. This is because even flipping the material or replacing the end mill can lead to the possibility of error, so it is safer to use the same end mill ( As much as possible) Grind out alignment holes and important features at once so you can make sure they are in the right position relative to each other. In the model above, the four alignment holes are squeezed on the top surface, but do not go through all the time because it is not necessary ( Insert pin from top). The center circle is an \"important feature\" and a cut that is squeezed out from the bottom of the block. The second and third pictures ( The top and bottom of the piece, respectively) Show this better. The problem with this design is that the alignment holes and important features are on the opposite side of the plate, which means I need to flip the material over and grind both out. This flip introduces errors when I flip to do the other side, which is never good. So I decided to pass through the four alignment holes-hole cuts ( See the last picture above) : In this way, I can Mill aligned holes and center features without flipping the workpiece. Let them pass For the function of the workpiece, the hole is unnecessary, because it only needs to install about 3mm of the pin to connect to another plate with the same alignment hole, but it is necessary for the machining of the workpiece. This scenario ( Similar situation) Explain why not only design for this purpose, but also for manufacturing. When you have a thin sheet, the torque of the vertical mill is more effective in potentially starting your material because it is lower and closer to the center of mass of the material. For small objects, the adhesion to keep the bottom surface is small, which increases the possibility that the mill will throw the object away. Therefore, it is important to design your work with this in mind. To fix this, you have two main options: add pins to fix your material on the sacrifice block, or add labels to keep the object connected to the rest of your material. The pin goes through your material block and prevents it from moving sideways on the sacrifice block when the vertical mill is cut. At least in the United States, they are usually in imperial units. They are a great, safe option but they work more: you need to grind holes ( Pin diameter 0. 01-0. 03mm makes it easier for them to slide together) For them, in addition to sacrificing the corresponding holes on the block that are aligned with those pin holes, go through your material. ( More information on how to do this next) I recommend selecting the snap ring for thinner parts, especially if you don\'t want to drill and complete the process. You just have to add the bumps in the second picture above. Don\'t select the entire bump entirely when you do the rough border boxes: Again, you don\'t want to cut them off completely. As you can see in the fourth picture above, the label is not completely cut out, so it connects the required machined parts to the rest of the material. This adds additional adhesive material to keep the position of the part. For the flip, you need to enter the PIN at the bottom of the material (i. e. The top of the material before the flip, so that the bottom after the flip becomes a new bottom) Also enter the top of your sacrifice area. If the alignment holes are symmetrical on both the X and y axes ( So they are completely focused on your material, in four corners or similar): Make holes ( Pin diameter 0. 01-0. 03mm makes it easier for them to push in) Before removing the material from the stage, in the material first ( Before you remove it, make sure all of your features are ground on the block! ). Return the end mill to the top of the sacrifice block and cut the exact same hole ( Make sure the total depth of your hole fits your pin- For example, if you program a 3mm cut for both, you can only install a 6mm long pin at most. The exact same hole can only be used ( So you can use the same. stl file) If the alignment hole is symmetrical. . . ( Big writing at the beginning of this paragraph). If you have a diagonal positioning pin hole like in the fourth image above, this is asymmetrical on both the X-axis and the y-axis. You need to flip the pin holes you grind on the acrylic resin ( So the hole will be in the top right and bottom left instead of the original top left and bottom right). This is because flipping the part used to match the pin hole basically requires a mirror image. The best way to avoid worrying about this is to do one. Stl file for a rectangular block with the same XY origin ( Lower left corner) And the same positioning pin hole position- Then, before flipping and in the sacrifice block, you can use this model to do pin holes on your material. See next for how this works. This positioning pin hole guide makes it unnecessary for you to worry about making a mirror image of both the X-axis and the y-axis for the positioning pin hole, as described in the previous step. Basically, you will use this file to cut the pin holes in the sacrifice block ( Used like imported, no need to flip vertically in Z direction) , In order to cut the pin holes in the actual material, please flip vertically in the Z direction, because you are milling the holes at the bottom of the material. In the new sketch, make a rectangle tangent to the object on all sides. In the same sketch, make sure to add pin holes in the correct position ( You can easily copy them into your sketch using the convert entities option). Squeeze the rectangle up to include all objects-- As long as it covers all your objects, it\'s OK to be higher. You should have a rectangle exactly the same as the XY origin ( Lower left corner-- It\'s very important because then you can keep the same origin)as your object. It should also squeeze the cuts for pin holes, no matter where they are. Save this as separate. The stl file you will use. As the attached note: When you grind this file, be sure to change your material settings in the milling software, because sometimes your block material is aluminum, but the sacrifice block is acrylic Can also switch vertical mill if necessary). Since your model ( And guidelines, if needed) Finally finished, let\'s grab your materials and factory! You can use calipers to measure the thickness of the stock material in order to get it down to the correct height. For example, if my final shape is 5. 4mm high, I may use 1/4 thick material ( I use mm in my model because metric is used elsewhere in the manufacturing world, but in the US, materials are usually sold in imperial units) Give me some profit. Then I will treat the surface of the material to 5. 4mm (so 1/4\"-5. 4mm is how deep I cut) But the clamp is first used to obtain the actual thickness of the material ( Because even the manufacturer that supplies your material has an error tolerance). Even with calipers, you get a fluctuating calipers reading as some parts of the material may be thicker or thinner than others. Decide which reading to use meets your job requirements: You can either be conservative or choose the middle position. I usually stay on the conservative side and not surface more and lose the material ( Conservatively, I mean I use the smallest reading to reduce the loss of the material and thus a bit redundant). To do this, measure your material in both axes (X and Y) Record the smallest readings in multiple places. Reduce your final height from here to get the depth that the conservative machining job should have on the surface: your final height will be a little larger than the desired size and you will end up with a little more material. Once you \'ve finished the calipers, it\'s time to tie the material to the sacrifice block. But before this: if you have material that is cut to the correct size ( Sometimes you buy 2 \'long material that is not suitable for your factory so all you need to do is cut it into 5 \") , There will be some jagged burrs on the cutting edge. This burrs may interfere with the surface contact of the tape between the material and the milling stage ( Because they will raise the edge a little) So you should use a file to delete them. You can still use a slightly damaged surface ( See the engraved face in the third picture above) Otherwise you might throw it away. This acrylic is engraved ~ 0. 2mm, but I know I will at least face it down 0. 5mm so the extra design will disappear later. If I can\'t guarantee enough adhesive tape on both sides, I avoid using materials that are damaged on both sides. If I try to face the material down, the tape may not be able to hold it in place and may be kicked away by the torque of the end mill. Apply adhesive tape on the bottom surface as much as possible to get the best adhesive effect. Use extra tape and cut off extra tape if needed! Also, try to keep the tape symmetrical on the bottom surface so your tape doesn\'t lean a little ( See the fifth picture above about what I mean) Keep in mind that your tape also has a limited thickness. If possible, press the material in a direction perpendicular to X-axis. This is suitable for extrusion materials such as polyethylene and aluminum, but not for acrylic because it is usually cast. For the aluminum in the sixth picture above, the extrusion direction is along the long axis of the rectangle ( Look carefully at the weak lines) So I parallel the long axis to the y axis. This is because I like to do the surface treatment steps in the X direction, because this stage will be more stable ( The stage moves only in Y, so there is no freedom to move in X; If the vertical mill makes the surface of the block in X, the vibration and displacement of the stage will be minimal) The change of material is usually perpendicular to the direction of extrusion ( Distortions like dog bones and bends usually occur on the shaft perpendicular to the extrusion). Once your material is arranged on the sacrifice block, press it. HARD. You want to maximize adhesion, so jump up and down and do everything you can to give more pressure to the tape ( Just don\'t push the stle stage and ruin your XY position). If your material is clear (think acrylic) You can actually see how well your tape works: Please see the last picture above. The dark part is where the tape actually sticks the acrylic block to the bottom material, and the light part is where the tape is not in full contact. It\'s good if you can completely stick all corners together, but if you can also stick the center together, it\'s best. Note: Don\'t forget to push the pins in if you need them! Before cutting harder materials like aluminum ( Some factories think that aluminum is soft, depending on the power of your factory. . . ) Sometimes it\'s a good idea to apply a thin layer of cutting fluid. This provides lubrication for the mill to make it easier to fall off the block and it also acts as a coolant so that the heat does not accumulate. Ironically, if you use a lot of fluid, it will also lead to the construction of the chip. Up, it captures heat near where you are milling. This is one reason why cutting fluid is not used at all: use soap to remove anything extra ( If it drops down, remove it from the sacrifice block because it interferes with the adhesive of the tape as a lubricant). In the picture above, you can see that using the cutting fluid causes the chip to gather around the milling position and capture heat. Unless the temperature rises enough to crush your Mill or material, this usually won\'t cause much attention, which is unlikely for small jobs like this. Goo gone is used to remove sticky residue from tape ( Mainly when your vertical mill is cut too deep, hit the tape, and tear the tape) On the sacrifice block, even on your vertical mill. It\'s great to remove the residue, but be careful not to overdo it: If you put a lot of glue, it will be difficult to clean up and make the tape more difficult to stick to in future applications. Hot water and soap are best suited to wash away the sticky matter that has disappeared as it is organic, but in any case: Be sure to wipe the sacrifice block thoroughly to remove all the sticky matter that has disappeared. If your subsequent work continues to be kicked out of the factory because it is not hard enough, it may be because there is a residue of sticky material ( Or blunt end grinding). When you choose your vertical mill, you have to consider a lot of factors: you can take time out, how much precision you need to work, how dull your vertical mill may be, and so on. For vocabulary related to end mills, see here. Different brands indicate that they have different specifications, but they are usually listed on the plastic housing of the vertical mill, and also on the website where you buy them. In the first photo, I have a 3/32 vertical mill. The first part, 3/32, represents the diameter of the end mill in inches. The next part, 3/8, cutting depth (in inches) How far the flute goes up so how far you can cut). The last number 1- 1/2 is the total length of the vertical mill in inches. The specs for Mills at the other end of the second and third picture above are listed differently: I included the specs for the second picture, but I \'ve forgotten what the third picture is (1/32\" end mill) So please do this if someone can provide some insight! I can\'t find information on how to read test tubes online; I just got to know them by asking my mentor. Understand the specifications of the end mill you may use and consider how far you need to cut in the model. Some vertical grinding can only be cut deep until no more grooves can be cut, so this can be a problem if you have deep holes. There are exceptions: for example, when using a 1/8 end mill, the cutting depth is 3/8 \", but the diameter of the shaft is the same as the groove area, so as long as you do not need to cut vertically and only rough machining, you can continue to cut more than 3/8 \"of the surface. For end mills with a groove area diameter less than the shaft, you can\'t do this because the program of the tool path does not take this into account, so the cone of your end mill may touch your material ( Since the program usually assumes that the diameter of the shaft is the same as the groove area). This is also a problem when you Mill high objects: the cone connected to the vertical mill and/or collet may run into your material because the shaft is only that long. See the fourth picture above for more information: When I Mill that polyethylene, I realize that I can\'t because of the remaining material ( The tall part you see) It may interfere with the collet connected to the axis and push it in. So I have to go back and drag my bounding boxes to include these extra materials so they are rough too. For materials that are harder than typical plastics, you may need to consider using coated end mills ( See the last picture above). Usually the coating may be titanium, but in any case the coating will harden the vertical mill so that it is more elastic and lasts longer when cutting these hard materials. However, they do not come here at a higher cost. . . Once you have selected end mills, Let\'s connect them to the machine. Once you \'ve chosen your stand mill, it\'s time to put it in collet and fix them on the machine with a wrench. Righty-tighty, lefty-loosy, right? I don\'t know about you, but such a simple motto is hard to stay awake when tightening collet ( Insert the end mill into the part before finally connecting to the CNC mill). I only remember where to tighten the wrench: the wrench on the right of the second picture above is on the top of the wrench on the left. If you pull these wrenches to each other in this position, then this will tighten your sleeve to the machine. The third picture above is the wrench on the left and the top of the wrench on the right ( Changed before). If you pull these wrenches to each other in this position, then this will loosen your sleeve so you can remove it from the machine. Over time, programming in tool paths takes longer and longer. When determining the tool path of the rolling mill, there are three main processes: surface treatment, rough machining and finishing ( Drilling is another type, usually less. used option). Surface treatment means simply cutting the surface of the material so that it is a flat plane relative to the end mill. This is usually used to obtain a uniform surface to better adhere the material to the stage or to lower the material to the target height. Surface treatment of the material before final adhesive cutting is particularly important for extrusion materials such as aluminum and polyethylene. The aluminum in the second picture above has a dog. boned cross- From its extrusion process ( You can see that when I run a file on it, the scratch is on the outside edge, so the edge is more prominent than the center. Because that\'s a dog. Boned, when you put the stock down for milling, it\'s hard to get good, complete surface contact with the tape and milling table. When you are on one side of the surface of the material, it ensures that the surface is uniform, so that when you stick it to the stage with adhesive tape, it will be in full contact for better adhesion, in this way, when cutting, the torque of the end mill is unlikely to kick the material off. So before you flip the aluminum, you will put the surface on one side of the aluminum, and then continue your final milling work. The material on both sides of the surface, if you care about the two close A completely parallel face; I skip this step once in a while to save time. Rough machining refers to cutting the material to obtain a rough outline of the desired shape uploaded to the software. It has a consolidation deposit ( For specifications, see the first picture above) This is different from the vertical mill you use, so this step hasn\'t completely defined your shape yet: cut off most of the material before the next step is done to make it a good, well, finished material polishing. These processes usually have predefined feed speeds and step sizes, but you can adjust them to save time if you want: there will be more on this in the next step. In general, you want to use the largest vertical mill, which can be installed in the gaps of your parts. This saves you a lot of time compared to using a thinner vertical mill. However, sometimes your large vertical mill cannot completely parse all your geometry ( Remember the finite radius of the vertical mill) So you will grind that ( After finishing rough machining and finishing) For a thinner vertical mill that can solve geometric problems --- You just have to focus on the parts that are not fully defined and you don\'t have to cut that much material. I said, you should also be completely rough and finish with a bigger vertical mill instead of rough machining with a big vertical mill, finishing with a smaller vertical mill is because the finishing allowance for a larger vertical mill rough machining may be too much processing for your thin vertical mill: The software must underestimate the number of remaining materials, and lead to the surplus of the remaining materials. Replacing end Mills is also the key to saving time: consider the shape in the picture above. It has a 1mm narrow groove, so only one 1/32 vertical mill can be installed inside. However, it will take a few hours if I also use the 1/32 vertical mill to polish the circle. This is not very good for opposing grinding, because vibration and fatigue stress may cause the vertical grinding to break (*gasp*). Therefore, before using the partial bounding box to select only the interior in order to rough and finish the groove with a thinner vertical mill, you can use a larger vertical mill for external machining. For larger end mills, you can drag the bounding box to fit the entire shape: due to the finer details, the larger end mill cannot be installed in the groove, the vertical mill will just follow this circle to cut the shape. Then, for the smaller part, keep the bounding box inside the circle so that it doesn\'t backtrack the circle ( Wasted time because it\'s completely resolved). Another way to save time is to make an outline-only cuts. Sometimes you don\'t need to polish the surface with a polishing step, you just want to define the vertical wall completely. In this case, you can select the outline- Cut for your profile only ( See the third picture above). I believe this is an option only when finishing, not rough. Another thing: rough machining forces you to remove the whole piece of material when you may not need it ( In the first image above, I only want a circle, but also a square block is deleted). If you don\'t want to waste your time grinding excess material, you can do a fake Rough the step by changing the parameters of the finishing step. The completion step tracks the material only if the completion allowance is assumed ( So most of the material is removed) So it doesn\'t make the square around the circle. Therefore, you can program the finishing steps, but change the feed speed and cutting depth to match the parameters of the rough machining step and add the finishing allowance. This is for an emergency: you don\'t want to do this all the time because the vertical mill will fall into the material, not by gradually removing the material along the outline ( The finishing assumption is that there is almost no material there, but since this technique replaces the roughing step, there is a complete material in the place where the end mill is cut). When the distance of the cut is selected ( Rough machining and finishing steps) I usually set the starting height-0. 01mm, because if you set it to 0mm, the vertical mill will skim the surface instead of really cutting. I also set the end height to final-0. 01mm, so that I will not decline all the way in technology. This is because I try to avoid damage to the sacrifice block as much as possible: if I mark it all the time, the adhesive force of the tape decreases due to cracks and holes on the surface. Also, I may cut into the tape, which will produce sticky residue on my vertical mill --- Not very good cutting. Usually, for the toolpath, I will use the machine preset feed speed and speed, but they are not always the best for the related material. For the image above, I am working on polyethylene and the chips stacked on the vertical mill interfere with its ability to cut well. With the best feed rate, this effect will be minimized. You can often stop the machine to remove the chip if you don\'t have time to do the experiment, but it\'s tedious. . . In addition, you can increase the feed speed and cutting depth in order to save project time. It really depends on the power of your machine and your experimental situation, but for plastics like polyethylene, I can increase the feed rate and cutting depth without any adverse effects on the processing work. This is risky for your vertical mill because the increased cutting depth is more demanding for your vertical mill ( Cut more every time) But I was able to reduce a job that usually takes 8 hours to 3 hours. For polyethylene, I found that I can adjust the rough and finish parameters: I increased the cutting depth by 25- 50%, feed rate 25% ( More not done well). Increase in speed increments-- Don\'t jump to the 50% increase without confirming 10%, etc. , because your vertical mill may not be handled well. Next, the positioning system must be calibrated before finally sending the toolpath to the machine. When your material is placed on the sacrifice block, the vertical mill now has to calibrate itself to know where it is and thus where it should be cut. To zero the end mill in the XY plane, select the position on the material, which will become the lower left corner of the model. This usually involves another software that allows you to move the end mill using the upper/lower/left/right buttons on your computer screen ( Unless they are built into the factory, use it in this case). When returning to zero in XY, remember (0,0) Technically, the point will be the center of the vertical mill, not the outer edge of the vertical mill radius. You may need a bit more error/excess material ( So move your vertical mill slightly in the northeast of the lower left corner) So you don\'t have to worry about running out of material in the X and Y directions ( Because although the vertical mill assumes that your angle is completely perpendicular to its inherent XY axis, your material may be tilted so that the angle does not align with the perfect XY axis). When you have the material to tilt the corner, be careful how you arrange it because your tilt should not interfere with the XY axis your end mill thinks. What do I mean? -- Please look at the second picture above. If you place the corners of the material like this ,( I have a rough overview of the black line. Perfect rectangle will be arranged) , Vertical grinding assumes that there is material in the gap between the inclined edge and the horizontal black line ( It marks the x-axis it assumes). However, there is no material there, so if your model has any geometry in that area, it will not be processed because, you know, there is nothing there that can be processed. Now, if you position your material like in the third picture above, there is extra material going through the assumed x-axis, which is better than not having any material. Note: This zeroing in XY assumes that the top surface is your final top surface, which means that you will go down the surface, rough and finish on this surface ( So don\'t flip because it will break your XY axis). Zero on the z axis, slowly lower your end mill until it is very close (~5mm) Insert a piece of gasket into your material (I use 0. 05mm -- Thinner and better so you are closer to your material) Before continuing down, under the vertical mill. Continue to push down and cooperate with the gasket test until you feel that the vertical mill is stuck on the gasket. How far you go down after touching the gasket is subjective, but I usually feel a little more comfortable (subjective. . . With experience, you feel it) Before removing the gasket and checking the spindle. For spindle inspection, open the spindle and push down. Listen carefully to the first signs of vertical grinding cutting into the material. Stop immediately after hearing and add an increment before setting the location to Z zero. Check Four Corners ( Or do it all if there are other prominent corners) Because these are the \"problem areas\" that are most likely to have fluctuations in Z readings \". After checking all corners, use the maximum reading ( So this will be the highest point) There is a conservative machining job that will end up with excess material instead of over cutting and cutting your sacrifice blocks. Once you zero your origin, cut it! When you suddenly hear the sound of the heart, your wound has been well for half an hour Your vertical mill makes a painful sound when it hits something, and you run over and press the red emergency stop button. NOOO. . . . When you stop in an emergency, your XY origin will inevitably be destroyed. I have moved the Origin 1. 5mm in both directions, it\'s more important than you intuitively think. Even if you use the technology I will describe below to zero, you may have a rough /-0. 05mm ( Suppose your work is quite rectangular, perpendicular to the axis) This may not be an opportunity that you are willing to take, in which case I suggest you start over. But if the machining work you are doing is not very accurate, please continue to read: in order to get the X zero position, do the spindle check with the vertical mill on the left side of the workpiece ( The first picture above). Once you hear the slight hum of the vertical mill touching the object, stop the spindle and set it to X zero. However, you also need to subtract the radius of the vertical mill (not diameter! ) In order to get the real X zero, because the center of the end mill is considered to be the origin. You will have some errors because you are not sure where you do the spindle check is right on your x-axis ( Edges can be tilted relative to the axis) But this is the best you can do. To get the Y zero position, check the spindle with a milling cutter in front of the workpiece ( The second picture above). Once you hear the slight hum of the vertical mill touching the object, stop the spindle and set it to zero. However, you also need to subtract the radius of the vertical mill (not diameter! ) In order to get the true Y zero, because the center of the end mill is considered to be the origin. Once you do this, set your Z origin as usual and you should go ( While not as perfect as emergency parking, at least as far as I know this is the best thing you can do). Once your work is done, it\'s time to take it out of the machine and use it well. Since you have used a lot of tape and enough pressure to ensure good bonding between the material and the stage, it is difficult to remove it. Most people just pry the two layers open with a chisel, but even then there is a specific strategy: always push your chisel/spatula etc when you remove the object. Move along the axis perpendicular to the direction of the stage movement. This is because the stage usually only allows movement in one direction ( MDX along the y axis-40 I used) So if you apply pressure perpendicular to it, you don\'t push the stage in the free direction, and you don\'t change your XY origin. As you can see in the picture above, I also tend to aim the corners as they are easier to pry up, but I still insert them from the left or right ( Perpendicular to the y axis, remember) Advance along the x-axis. Sometimes machining is not good enough when using metal. It\'s time to shine when dreemel knows. I have to admit that I know very little about polished metal, but the work I have tried so far is this: I used a Dremel drill with steel wool, this does a good job of making the dull aluminum color clearer and shiny. Also, my grades are better ( At least subjectively) When I polish along the direction of the metal extrusion line, because there is some smaller space, I can\'t reach it with bits, so it looks natural to have all the faint lines in the same direction. I also used something called polish. I just use a rag ( Microfibre is the best. Rub some thick substance onto the metal and it will oxidized/blacken after a few minutes. Then I wiped it with a piece of cloth and wiped the metal and it turned out to be very shiny --- All the processing marks are gone, including the lines and scratches on the steel wool I used before. It also makes the aluminum sheet softer- The feeling is hard to describe, but the edges look more rounded and the surface is just. . . It is softer and more pleasant to touch. This is all I have now. Hope I don\'t scare you too much with all the words ( You should look at my notebook. . . More intensive). If you have more suggestions (Or correction-- Comment on my work) Because my study is still in progress, please comment below! Enjoy.