Hello everyone, today I want to introduce the introduction to sheet metal design. Sheet metal generally thinks that it is a car shell. There is no mistake. The car shell is one of the parts of sheet metal. Manufacturing process Next , there is a way to design, which really conforms to the design drawings and appearance that can be produced. Here , let’s watch an animation first to review what kind of manufacturing process of sheet metal is. After watching the animation, we probably have a concept . Here is actually simple. One can think of sheet metal as it is an iron sheet industry , so you can think of it as origami, it is a board, and then it may have thickness, thickness , and then fold it into the desired shape. This is what we generally start with. The more commonly seen form , let everyone understand here, and I will explain other details later. Sheet metal design is generally the most commonly heard, or when checking information, you will see sheet metal engineering drawings and sheet metal expansion drawings. Here you may be in When I hear these two terms, I often take a big step back because I think it is very difficult. Here I will first introduce the sheet metal expansion diagram . The blanking action required for the first level is here to let you know what blanking is . Blanking means to take the material. Generally, sheet metal is a large steel coil. The steel coil is cut to a certain length . After leveling, it is a whole Zhang imagines it as a whole very large piece of paper. This very large piece of paper must be made into the shape we want The customer provides the final size, and then the sheet metal factory converts it into an expanded drawing based on the final size, so you can think of it as cutting the iron plate into this shape and then doing the next process, so the first action is to cut the material . When doing entry , laser cutting will be used more, because there are two types of sheet metal: those with molds or those without molds. Generally, if you have molds, you will do more without molds, because if you have molds, you usually have to have certain experience and certain skills. The amount (quantity) will move to the mold. In today's industrial environment with a small amount and a large amount, the whole environment is like this, so now you will see that most of the laser cutting is used, and some parts are cut by flame because some plates are too thick. Laser cutting If it is not so thick, I will also use this part to let everyone understand the unfolded form first, and then look at what is a sheet metal engineering drawing. Here you don’t need to think too much about it, just imagine it as the same as the general processing drawing . Look at the upper part first, just imagine what the desired shape and size are, and mark it . Usually, when making sheet metal, you should pay special attention to it. If you are not symmetrical, because the next process may be to do folding When bending and bending it is directional, there may be a problem of folding the wrong side. After folding the wrong side, if it can be saved, drill more holes. If there is a deviation If the workpiece is too large and cannot be saved, it means that the workpiece will be scrapped. Usually, if it is directional and important, it is generally recommended to mark it on the drawing. The people who are working on the process here see that you have marked the directionality when bending. I will pay special attention to which side should be facing up . There are usually two types of sheet metal markings: one is inside the bag and the other is outside the bag. What is inside the bag and outside? As shown above, assuming it is 2.0T, the outside of the package is marked with 29. Here, the height of the package is 17. Here, pay attention to the sheet metal design. You are in the same material. You cannot have two thicknesses . Think of it as the same piece of paper. This piece of paper is The same thickness , so pay special attention to this point. Let's take a look at the inside of the bag. The inside of the bag is the opposite of what it was just now, that is, the internal size is marked. Like this, the inside of the bag becomes 25. Here is 15. Here are some simple marking methods for your reference. If you draw a shape in the annotation, here is a U shape. If the size is inside, it means it is inside the bag. Like here, it is inside the bag. 2T means the length is 50. Usually, there are such annotation methods. Sheet metal is a simple form without holes, just a simple U or Yes, L can be marked in this way. If it is complex, there is no way to express it. It is recommended that you still produce engineering drawings. It will be more appropriate. For example, it belongs to the outside of the package. 17 is 50 long like 29, 17, and 2T. Here , let everyone know what the development drawing and sheet metal engineering drawing are How thick the plate is and what is the difference and influence between the thickness and other holes? At the beginning, you must decide how thick the plate should be, so you must pay special attention when designing the sheet metal. There are absolutely no two thicknesses of the same material. This is 2T, it is 2T, here 3T It is 3T , etc. and so on. There will not be two thicknesses on the same plane. Here you should pay attention to the introduction of cutting. Cutting is because it is an entry. Today , the main explanation is laser cutting. Laser cutting can be Imagine that it is a laser beam hitting the sheet metal , and it will be cut off wherever it goes. So in fact, the laser cutting process is very fast. You may be wondering why the laser cutting is so fast , but we are often waiting for the sheet metal. It takes so long for the factory to make it . In fact, laser cutting is the first process in the production schedule . In fact, there are others in the future . It depends on what we design. If you are just a simple tablet, the speed will be faster It depends on your thickness. Whether the thickness of the sheet is special or not commonly used. If the thickness of your sheet is special, it is rarely used in the industry. It may take a long time for you to wait for the material. It is possible to adjust the goods after the adjustment. This thickness is only used by you, and it may take a long time because there is still a queue. Usually , the same thickness will all be lined up together for laser cutting. Therefore, the same laser cutting may cut the things of several manufacturers, so it will be discovered that the first process requires these pre-operations , which leads to the fact that the time to get the samples is not as fast as we thought, and then we return to the topic to know. Yes, how to design the hole size of the plate . Generally, we will give you suggestions . The thickness of the plate is used as a reference. If we look at it today, it is a 1T or 2T minimum hole diameter. It is recommended to be similar to the plate thickness. The minimum assumed thickness is the 2T minimum hole. It should not be less than 2 , because it is possible that the laser cutting cannot be cut, or the hole may be unusable or deformed. Here , everyone should pay attention to it . Relatively assume that the thickness today is 5T, and this hole is 3.3 . Here, the sheet metal factory will tell you that this 3.3 can't be made. Here we have to pay attention to this part. If you really need to use 3.3 holes, you need to use other methods . Go to drilling. There are some designs here that can’t be overcome. This method is used to overcome it. But if possible, it is best to make the hole as large as possible. The minimum should not be smaller than the thickness of the board. It can be cut out smoothly. Here is an analogy for everyone to understand . It should be noted that the thicker the plate, the smaller the hole is, the more difficult it is to cut . When designing, pay attention to the thickness of the plate and the diameter of the hole . Let everyone understand here , and there are others later. Matters needing attention The next thing to introduce is sheet metal bending. Generally, sheet metal bending is folded with a bending machine. Of course, some of them are special and may be formed with a mold. Today, the most important thing is to explain to you with a bending machine, so when folding, you will usually find There must be an R angle in sheet metal bending. This R angle may be very small or it may be very large. We have something to do with the thickness of the plate. Of course, the thicker the plate, the larger the R angle will be. This part is also related to the bending machine of the sheet metal factory and its mold ( It depends on how big the R angle of the knife is, so the bending radius is not fixed, but it can be used as a reference. Generally, the inner diameter R angle is usually the same as the thickness of the plate. You can use this basis for drawing, of course not . Certainly it may be smaller, but it is better to use this basis as a reference . Here is the bending length . Generally, look at sheet metal bending. It has a length limit . The shorter it is, if it is too short, it may be It can't be folded. Like here on the screen, the right side is relatively short, and this part may not be folded. How do we design it? Sometimes when it is very short, we need to learn about the shortest bending of sheet metal in general bending. For a reference , the back of the board x3 is its most bent length . Here is the way inside the bag. Suppose you are 1.6T here. The highest point measured from the inside of the bag and the inner diameter is 4.8 , which is three times the board. Thickness and height of course, this is just a reference value. Basically, don’t design it too well. It’s just three times . Make it as high as possible, make it five times or six times, and don’t make it too short . If your design doesn’t need to be so short , try not to be so short . This will make the process simpler and easier, and so on . For your reference , if possible, design as much as possible. It may not be too short . If it is too short, it will be a problem when bending. Let’s learn more about it. There will be deformation problems when bending . First, let ’s look at the first one. It's perfect when drawing. You draw a perfect circle and it's a perfect circle , but when you are just at the folded edge or very close, when you get the sample in the real process, you will find that its hole is deformed. It's not a perfect circle, it could become an oval or an irregular circle, so be careful if you design the circle for what purpose, assuming you're just going to run wires or just put screws through it. It might be okay if the hole is deformed , the hole should be bigger. If you want to assemble, you have to pay attention to whether this design is possible or not. Here we have to find out , and sometimes , some holes are made very close to the folded edge . After bending, this place will actually be squeezed , so you may find this The surface is not flat, this side will protrude, that is because the hole is too close to the folded edge, here is also a reference for everyone, as far as possible away from it, at least twice the size of the hole, it is recommended not to be so just, assuming this side It is 10mm at least from this side. I would recommend using 1.5 times. Of course, the bigger the better, there will be no problems here . The strength is better, and it is not easy to deform . There is another one to see. There may be a kind of broken. The hole is broken in this form. It is broken on both sides. It is also at this bend. Sometimes you will find that the sheet metal factory directly cuts two lines for you . That is because when folded in this way, the surface will be more beautiful and less difficult. There will be deformation problems. Sometimes it will be found that when you get some samples , you will find that the sheet metal factory has already cut the lines for you directly at some bending points, which means that the sheet metal factory may have predicted that this place will deform , and you will do such a service in advance here . Let everyone know about the bending deformation and how to design the length when folding. The next thing to introduce is sheet metal welding. Generally, if you use sheet metal welding, you will find that the changes in sheet metal become more because sometimes you are doing folding. When bending, there are some shapes that cannot be folded. Sometimes there are restrictions on the folding machine, and it may not be possible to fold out part of the angle because it will interfere, etc. or the shape is relatively special. Welding is used to overcome it . Briefly introduce a few kinds to let everyone know the first one is electric welding. Electric welding generally has a welding rod. After the welding rod is energized and arc started, it can achieve the welding action, so it can be roughly seen from the welding bead. Generally , electric welding platform language is called "squatting electric estimation" , so in the When welding, you will find from the weld bead that there will be a layer of black after welding, so you will see that there will be some hammers next to it to knock out these black beads. If you see this movement Work means that it is doing electric welding process, and then CO2 welding, which is our most common welding method. Usually, welding can be done manually. Many of them are equipped with robotic arms because it will have an automatic feeding system, so the welding speed is relatively fast. The whole process of the robotic arm will be much faster. This is the most common welding method. The third method is argon welding. The argon welding Taiwanese language is called "Aru Meng" . There will be some gas during welding, which is actually harmful to the human body. During side welding, there will be more materials (materials that can be welded), which may be stainless steel , aluminum, copper, etc. You will see the welding action of " Alumeng ". Let everyone know about it here. Here are a few types of sheet metal that will be used. As shown in the picture, it is a box. The box can be folded out with a folding bed, but there must be gaps next to it after folding. If the gaps are beautiful and beautiful , or they need to be filled with water and substances I don’t want water or other substances to leak out. What should I do? If it’s just a simple sheet metal bending , there will definitely be gaps , and there is no way to fit very well. At this time, it can be welded . Welding is to make a weld bead on this side and then melt it in After it is inside, it will be filled in this place. Of course, if you want to be beautiful, this place will usually be grinding to make it smooth. So generally, if the welding + grinding process is usually more expensive, it is because the process, labor, etc. will be It needs some cost on the inside and there is a cover on it. You have to make it one piece. We also need to do welding here . Let's say you have an L shape, but because of the lack of strength, you need to make a rib. This rib can't be used with a folding machine. It is made by folding. Maybe you can fold it up from the long ears on both sides, but it is basically separated. If it is not fused together, the strength will not come out. At this time, it is quite convenient to use welding . The strength becomes better. Special attention should be paid here . Generally , welding will reserve space for it. It is recommended that you should at least 5mm or more. Of course, it depends on what kind of welding method is used . 7mm can be reserved, at least not less than 5mm . Of course, it is recommended that you do not grab it. If you can , try to use as much as possible. It will be easier to weld. If it is other welding methods , I will leave it to you to do a research. Some are like electric welding, you may need to reserve more. The weld bead will be larger or the electrode is thicker. This may not be enough . Let everyone pay attention to it. After the welding is completed, the strength will come out, and you don’t need to use too much. Material, through welding, the material cost will be saved and the strength will be better. For a TV stand, it may also be used in this way to cut out a flat plate with laser cutting, and then cut out another flat plate . After bending, it becomes a U shape. U is doing welding with the plate, sometimes there is no gap left because there may be assembly problems here, the welding may have to be welded elsewhere or It is said to be smoothed after welding. Generally , if the welding is to be completed and smoothed, it is necessary to chamfer or leave a gap. The weld bead should be penetrated into the starting surface and the two iron materials should be fused together, so that there will be no false welding. Because welding sometimes Fake welding means that it does not really fuse the two materials together , it is fake welding, so it may be broken by applying a little force or hitting it with a hammer , which means it is fake welding. This is because it is very, very much in-depth. It is enough to understand this first to get started. Then I will introduce sheet metal tolerances. The most common mistakes in sheet metal tolerances are that the sheet metal tolerances are very fine . What does this mean? That is, the tolerance is very small. In fact, when making sheet metal, it is necessary to get out of the tolerance thinking of processing. Because sheet metal is compared with processing, processing refers to the most common lathes and milling machines. Its tolerance is not so accurate (sheet metal), so Often, when there is no way to escape this framework, the design is often not the same as expected, and the tolerance definition is very small. After the design is completed, I find out why there is no way to make the sheet metal accurate? Our drawings are clearly marked like this? Here We have to think in reverse. In fact, it is because the manufacturing process cannot be achieved. It means that there is a problem with our design. Here , I will give you the concept first. Then when doing sheet metal design, we must have a concept. The tolerance is drawn directly on the drawing. The concept is different because if the sheet metal is laser cut as an example, assuming that the hole needs to be larger, and that the M10 screw needs to pass through , you can draw it. It happens to be 10mm . After the sheet metal is made, it may be found that the 10 hole may be smaller than 9.9 or 9.8, etc. If it is a 10 workpiece to pass through, it will be stuck. You may want to say that the tolerance on the drawing should be greater than 10 Why is there still no way? This is because the drawing we provided here is 10 laser cutting, and it is cut according to 10 of the drawing, so there is no way to set the tolerance . What should I do at this time? Design it directly. If you are bigger than 10, you can directly draw a hole larger than 10. Suppose you want 10.2, then draw 10.2, if you want 10.5, then draw 10.5. Don't draw 10. Here , let's take a look at the picture, everyone will be more clear. It is a wrong demonstration. Here is the method just introduced. Suppose 10 is your standard, but you are bigger than it . 10 bars and 15 bars. Use annotations when laser cutting sheet metal . If it notices it, it will directly help you to change the drawing. Generally , it is not very good to change it . Just go directly, you give me 10, and I will cut 10 for you. Pay attention here and Some tolerances may be marked here because it is not necessarily what you want. It may be sheet metal, especially when bending, it may deviate by 50 lines. If you mark too finely, you may not be able to do it, and then there may be some angle requirements. In fact , when marking sheet metal, there are very few markings to set tolerances. Generally , it is like this. Give it a size. When designing, we should pay attention to the deviation error of sheet metal . If there is a deviation of 50 pieces, it is actually acceptable. Because the error of sheet metal will be larger, and even the angle may not be so thin. 0.02 is basically to be done. It's not easy unless there is a special process that pays special attention to it , so it is generally not used to mark this thinness. If it is + - 0.5 degrees, maybe it can be done, but 0.02 degrees is really too thin, like here, there is also a marked width tolerance. On the side, maybe the sheet metal factory will pay attention. If you don't pay attention, you will directly give 50 to you . You will find that it is not 50 after you do it. Maybe 49.9 can't be released . We will be more troubled here. Here is a correct demonstration of how to go. Mark it. It is mentioned here that you can draw what you need. For example , if it is larger than 50, it does not matter if you do 50.2 or even 50.5. If your design allows it, you must pay special attention to the sheet metal design. Note that when assembling, it is not a precise fit . It is a common fit that is often seen. It may be functional, and some design adjustments need to be made. For example, if you want to perforate here, the 10.5 is larger. Assuming that it is an M10 screw , the size is 50. Yes, when bending like here, I usually don’t set tolerances for it. Assuming that your hole is very accurate , sometimes it may not be possible to use this method. You may have to ask the sheet metal factory to bend it and then use a milling machine to process such a hole. It will be accurate . Let everyone understand the definition of tolerance and what to pay attention to when designing. Finally , let’s summarize the introduction to sheet metal design. Today , I will introduce it to you from an introductory perspective, so it is all done by laser cutting. Demonstration and explanation I just noticed the relationship between plate thickness and holes, as well as bending and height and deformation problems, as well as the welding method between sheet metal and sheet metal and its variability, as well as the dimensional tolerance requirements after the sheet metal is finished . To define it, these are actually explained on the drawing and in the computer, so the sheet metal design actually needs to be matched with the actual thing , so if you have the opportunity, you can do the sheet metal design, then give the drawing to the manufacturer to make it and get it after production. The actual sample is actually a very important cycle of sheet metal design. Design , drawing, and giving to the sheet metal factory. There may be some discussions in the middle . After the discussion, we will get the actual sample and then look back to see if our design conforms to such a sheet metal design. It is very, very necessary to see the actual things so that we can really have a coherent sheet metal design. If it is just on the drawing , there is no way to do sheet metal design, because there are so many problems that we cannot see, so if we can design it and then Really made is the real sheet metal design Of course , there are many extensions of sheet metal, such as molds , blanking molds, forming molds, or like cars with some door sheet metal designs and some curved surfaces. These are relatively advanced. Today, I will introduce you to these kinds of How to get started designing it So the most important thing here is to emphasize to everyone that the sheet metal design must be matched with the actual thing. After you design it, you can actually get the thing and go back and review it to see if it is consistent with the design. In this way , a cycle can be used to achieve the correct design process. This way , it will not be too far from the actual one. Today's teaching ends here, and we are looking forward to the next teaching Bye~ Bye~
