What are the learning skills of CAD?

There may be many people who have just started painting, but this is not correct. It should be to make various settings, including layers, lines, fonts, labels and so on. It is very necessary to make all kinds of settings. Only when the settings are reasonable can we lay a good foundation for our next drawing work and make it clear, accurate and efficient. Let's talk about the layer first. It can be said that the definition of layer is the most critical setting of the whole AUTOCAD software, but I found that our company does not have too many clear regulations on the layer setting of employees. Sometimes when I open some colleagues' DWG drawings, I can't help laughing and crying when I look at dozens of floors, and then I see that most of the primitives are on the 0 th floor. As for what should be on different floors and what should be on one floor and not on the other, similar problems abound.

What are the principles for setting layers?

First, as little as possible on the basis of enough. No matter what major or stage the drawings are, all the graphic elements on the drawings can be organized according to certain rules. For example, architectural drawings can be divided into columns, walls, axes, dimensions, general dimensions, door and window lines, furniture and so on. That is to say, in the plan of architecture specialty, layers are defined according to columns, walls, axes, dimensions, common Chinese characters, lines for doors and windows, furniture, etc. Then, when drawing, the primitive should be placed in the corresponding layer of which category. As long as you can classify all the primitives in the picture, the foundation of layer setting will be set up. However, is the classification of primitives as fine as possible? Wrong. For example, on the building plan, there are doors and windows, and there are many stairs. Is it divided into door layer, window layer, platform layer and stair layer? Wrong. If there are too many layers, it will cause us inconvenience in the drawing process. Just like doors, windows, steps and stairs, although they are not the same kind of things, they all belong to the warning line, so they can be managed at the same level. Therefore, the first principle of layer setting is to have as few layers as possible on a sufficient basis. Two meanings, 1, that's enough; 2. streamline. The situation of each major is different, so you should figure out what is the most reasonable.

Second, the use of layer 0. Many colleagues like to draw on the 0 th floor, because the 0 th floor is the default floor and white is the default color of the 0 th floor, so sometimes it seems that the display screen is glistening. This is absolutely not desirable. Layer 0 cannot be used for drawing, so what is layer 0 used for? Used to define blocks. When defining a block, first set all entities to level 0 (except in special cases), and then define the block. In this way, when inserting a block, the block is the layer it is inserted into.

Third, the definition of layer color. Layer settings have many properties, including color, line type, line width and so on. When we set the layer, we should define the corresponding color, line type and line width. At present, when many colleagues define the color of a layer, they use whatever color they like according to their own hobbies, which is unreasonable. There are two points to note when defining layer colors. First, different layers generally use different colors. In this way, when we draw, we can clearly distinguish colors. If the two layers are the same color, it is difficult to determine which layer the operation element is on when displaying. The second point of the layer color definition is that the color selection should be based on the thickness of the line width when printing. When printing, the wider the linear setting, the brighter the color of the layer should be; On the other hand, if the line width is only 0.09mm when printing, then the color of this layer should be No.8 or similar color. Why are you doing this? This can intuitively reflect the thickness of the line shape on the screen. For example, look at the attached drawings. Column layer (ZU) and WAll layer (wa) are the thickest, so one is yellow and the other is cyan, which is brighter in AUTOCAD. When printing, the line widths of the filling layer (H) and the furniture layer (fur) are defined as 0. 13mm, so when selecting colors, the darker No.8 and No.83 colors are also used. The benefits of doing this, everyone in use, slowly understand. In addition, white belongs to layer 0 and DEFPOINTS, so we don't want other layers to use white.

Fourth, the setting of line type and line width. Before setting the line type of the layer, mention the command LTSCALE. Generally speaking, the setting value of LTSCALE should be set to 1 to avoid confusion when communicating drawings. There are three commonly used line types, one is continuous line, the other is dotted line ACAD_IS002W 100, and the third is dotted line ACAD_IS004W 100. Hide, dot, etc. Not recommended in previous CAD version 14. The setting of line width is also particular. Whether a drawing is beautiful and clear is one of the important factors, that is, whether it has structure. A picture, thin line 0. 13, medium width line 0.25, thick line 0.35, rich. Printed drawings, at first glance, can also distinguish different types of primitives according to the line thickness, where is the wall, where is the door and window, and where is the label. So when we set the line width, we must make it clear. If a picture is a kind of line width, which can be generally described, then it can be said that the door and window lines are thicker than the wall lines. There is another point that we should pay attention to. Now we have two drawing specifications. One is to print in proportion. At this time, our line width can be 0. 13.25.4. If we don't print A3 specifications according to the scale, we should set the line width to be 0.09. 15.3 smaller than the scale, so as to make the thumbnails look clear. When setting the layer, there are mainly the above aspects to pay attention to. In addition, when drawing, it should also be noted that all attributes of graphic elements should follow the layer as much as possible. I don't want this line to be a WA layer, but the color is yellow and the line type becomes a dotted line. Try to keep the attribute of the primitive consistent with the layer, that is, the attribute of the primitive is Bylayer as much as possible. This will help to improve the clarity, accuracy and efficiency of our drawing.

Fonts, label settings and CAD template files

There are two kinds of fonts that can be used in AUTOCAD software. One is fonts stored in AUTOCAD directory, and the suffix of fonts is shx. This is a proprietary font of CAD, and English letters and Chinese characters belong to different fonts. The second category is fonts stored in the WINNT or WINXP directory (depending on the operating system used by the system). The suffix of font is ttf, which is a common font in windows system. Besides CAD, other softwares such as Word and Excel also use this font. Among them, the Chinese character library already contains English letters.

When we define fonts in CAD, both fonts can be used, but they have their own characteristics, so we should use them differently. The first font with the suffix shx is characterized by occupying less system resources. So generally speaking, I recommend using this font. Our company provides three fonts: SCIEIC. SHX, sciei. shx, SCIEIST 01.SHX, in which SCIEIC. SHX is Chinese font, sciei. shx is English font, and SCIEST 01.SHX is English font, with common structural professional symbols. I strongly recommend that all drawings of our company use three font files: sceic.shx, SCIEE. SHX and SCIEST 0 1. SHX, so that drawings can be unified and formatted.

When will ttf suffix be adopted? There are two situations. First of all, your drawings and documents should be communicated with other companies. In this way, using fonts such as Songti and Bold can ensure that other companies will not have any problems in opening your document. The second situation is when making plans, covers, etc. Because there are too many font files of this kind, and the styles are varied, varied and beautiful. So you can use this font when you need to teach beautiful words.

There are some things to pay attention to when defining fonts.

First of all, it is also the principle that as little as possible under sufficient circumstances. This should apply to all settings in CAD. No matter which setting, the more CAD files there are, the larger the CAD files will be, which may also affect the operation speed of the software when it runs. More importantly, the more settings, the more prone to errors in the classification of primitives.

When I use CAD, there are generally only two font definitions except the default standard font. One is normal definition, and the font width is 0.75. Generally all Chinese characters and English characters use this font. The second font definition uses the same font as the first one, but the font width is 0.5. This font is a special font I use when dimensioning. Because, in most construction drawings, there are many small sizes crowded together. At this time, using a narrower font will reduce a lot of overlap.

Label setting

There are a little more options in the annotation definition, but there are not many places to pay attention to. Generally speaking, I will define a setting. Under special circumstances, I will modify its properties separately, and then brush others with a format brush. Let me introduce my usual setting of annotation definition (1: 100 scale plotting).

Straight lines and arrows: all colors and line widths are selected as Bylayer, the arrow size is 150, and other data are generally 100~200.

Text: For the text style, choose a font with a width of 0.5 as described above, the color is still Bylayer, the text height is 350, the text position is vertically above, horizontally centered, offset from dimension line by 60, and the text is aligned with dimension line.

Other options are adjusted as needed, regardless of the place.

Unit setting (unit).

Among the options of unit setting, I found that some people like to choose 0 for the precision option of length, that is, taking units as the unit. In this regard, I suggest changing it to 3~4 decimal places. In the first chapter, I emphasized that accuracy is one of the three basic points of AUTOCAD. If we define the length accuracy as one bit, we will ignore many tiny errors, such as the line segment of 1000, which is actually drawn as 999.97.

It is troublesome to define the above before drawing every time, so AUTOCAD company provides us with a very good way, which is dwt template. Every time we create a new drawing, CAD software will let us open a dwt template file, which is acad.dwt by default. After creating our own set of custom settings, we can create our own template file to save all the settings and definitions. My dwt template is some drawings that I have carefully selected for several hours, including a simple plan, an elevation, a section, a staircase detail, and dozens of commonly used blocks (of course). In this way, every time I do a new project, I can open this module and start working. Some people may ask how to create dwt files. It's simple. When saving the file, select Save As, and then select dwt as the file type.

I have finished all the settings in AUTOCAD, and finally I will talk about the command Purge. Purge this command can clear all useless settings, blocks and other information in the picture. I suggest you use it more. Clear it almost every time before saving.

Finally, to sum up, the clear and orderly setting in AUTOCAD is the cornerstone to realize the three basic points of "clarity, accuracy and efficiency" in the use of CAD software. Therefore, I strongly appeal to all departments of the company to establish a set of standard settings suitable for their majors as soon as possible and put them into practice. If each major can be standardized and standardized, it will certainly improve efficiency not only within the major, but also in the connection of various majors and the submission of materials.

Principles for setting common commands and shortcut keys

There are many commands in AUTOCAD software. How can we master the main commands and use them reasonably? I often discuss with others that in CAD, there are generally several ways to draw or edit a graphic element. As a qualified cad draftsman, you should use the most suitable method reasonably.

Let's look at the commands in CAD first. We can divide them into several categories. One is drawing, the other is editing, the third is setting, and the fourth is other classes, including annotations and views. Let's analyze them one by one.

The first category is painting. Commonly used commands are:

straight line

Xline construction line (used to draw auxiliary lines)

Mline double line (often used to draw wall lines, other line types can be defined by themselves)

Pline polysemous lines (most primitives composed of line segments are defined as polysemous lines if they can be defined as polysemous lines, which makes it easier to choose).

Rectang rectangle (actually four closed polysemy lines)

Arc arc

Circle circle

Fill the pattern (pay attention to the scale of the pattern)

Boundary boundary (used to calculate area, filling, etc. )

Block defines a block (you need to put all entities used to define a block at level 0 and change all other attributes to bylayer).

Quick insert insert (compared with -insert, one will pop up a dialog box and the other will not)

The second category, editing category. Commonly used commands are:

Matchprop feature matching (equivalent to the format brush in word, which is often used to brush the operation primitive into the correct layer)

Hatchedit hatch pattern editing (just double-click the hatch pattern with the left mouse button)

Pedit polysemy line editing (it can also be used to connect several end-to-end line segments into polysemy lines)

Erase erase

Replica

mirror image

Offset translation

Array array

Move, move.

Rotate, rotate

Scaling

stretching

Lengthening (not commonly used, but convenient when it is necessary to lengthen non-horizontal or vertical line segments; ! The same function can also be achieved. Let's find out for ourselves first. )

Pruning reduction

Expand, expand.

Interrupt interrupt

Round corners

Explode breaking (can be used to break fragments, polysemy lines, double lines, etc. )

Align alignment (not commonly used, but very useful when drawing some inclined graphics. You can align the picture and adjust it back to the original angle after painting. And UCS are two concepts)

Properties attribute (like ddmodify in 14 version, you can call up the attribute table, and you can view and modify almost all the attributes of the primitive in the attribute table, which is very useful).

Explain the commands of drawing class and editing class again.

First, in drawing, generally speaking, what can be done with editing commands should not be done with drawing commands. In the process of using CAD software, although drawing is always talked about, most of them are actually editing drawings. Because editing primitives can greatly reduce the probability of inaccurate drawing primitives and improve efficiency to some extent.

Second, when using the drawing command, you must set the capture (capture setting later) and switch F3.

Thirdly, when drawing and editing commands are used, in most cases, orthogonal mode is adopted and F8 is switched.

Fourthly, as a cad draftsman, you must master and skillfully use the drawing and editing commands listed above. Other drawing and editing commands not listed should be understood and used when appropriate.

The third category is the setting category. I have said a lot before, so I won't repeat it.

The fourth category, others. There are many contents in it, which we will describe separately. (This will involve commands in Express. )

Let's talk about how to customize shortcut keys.

The definition of shortcut keys is saved in acad.pgp file. After the 2004 edition (or the 2002 edition, I can't remember clearly), I changed the catalogue. You can search in windows yourself. Shortcut keys can be defined freely according to everyone's preferences. However, in my opinion, freedom does not mean casually, and there should be some principles.

First, don't be vague and try not to use completely irrelevant letters. For example, for the command copy, do not use the letter V to define the shortcut key. This is easy to cause misunderstanding and forgetting. Even if you know it by heart, people will be dizzy when they get on your machine.

Second, define shortcut keys according to the frequency of each command. When defining, the principle of "1 letter-1 letter repeated twice-two adjacent or similar letters-other" is adopted in turn.

Take the simplest example, copy the circle. In the default setting of cad, copy is co/cp and circle is C, which is absolutely unreasonable. Generally speaking, copy is used much more frequently than circle, so first of all, C should be defined as the shortcut key of copy. Then for circle, you can use cc (the first and fourth letters) or ce (the first and second letters), both of which are occupied or unaccustomed, and then use ci.

For common commands, my suggestion is to use shortcut keys. It takes a lot of time to use shortcut keys than to click icons or choose commands on menus with the mouse. Be sure to get into the habit of using the left keyboard and the right mouse. What are common commands? I suggest that commands that appear more than five times a day on average should be classified as common commands.

After you define shortcut keys according to this principle, you will definitely improve a lot of efficiency after practicing for 1~2 days.

Layer control command, view command, element selection method

Layer control command and view command are both commands to assist drawing, but these commands are very critical, and proficiency will greatly affect the efficiency of drawing.

Let's look at the commands related to layers first. In fact, most of the commands related to layers are in Express (it seems to be in Bonus in version 02). After AUTOCAD is installed, it will only appear after it is completely installed.

In the layer command, the first one is of course the layer, the layer property manager. The specific content has been discussed in detail before, so I won't repeat it this time. Other commands related to layer control are how to conveniently control the "switch (display)", "lock" and "current layer" of a layer in the process of drawing, and conveniently convert the layer attributes of drawing entities.

Commands related to the current layer.

Ai_molc changes the current layer to the layer to which the selected entity belongs. There is this command in the toolbar, which should be familiar to everyone.

Laycur (Change to Current Layer) Changes the layer to which the selected entity belongs to the current layer.

Commands related to the switch.

Close (Layer Close) Closes the selected layer.

The Layiso* (Layer Isolation) graphic display retains only the selected layer (Isolated Layer).

Layon* (Open All Layers) Opens all layers.

Commands related to Lock.

Laylck locks the selected layer.

Layulk unlocks the selected locked layer.

Layerlckiso* locks all layers except the selected layer (command in the plug-in "Free Mini Building Tool")

Other layer control commands

Layerp reverts to the previous layer state.

Laymch (layer matching) changes the layer of the selected entity to the layer of the last selected entity (similar to matchprop, but the order of selecting entities is just the opposite).

I hope you can spend a little time getting familiar with and mastering the layer commands. Of course, the premise is that the provisions on the setting and classification of primitive layers in the drawings are clear. If you can't do this, nothing is possible. There are three commands marked with * above, which are very useful commands and you may usually ignore them.

There are three types of view commands.

The first category: redraw redraw, regen rebirth. Redrawing is common. When some auxiliary display points and auxiliary display lines cannot be cleared by redraw, you can try regen.

The second category is the view zoom category. This category mainly focuses on various branch commands around zooming. Commonly used are:

Zoom-default real-time zoom

Zoom-p returns to the last view range.

Zoom-3D dynamic zoom view

Zoom-a displays all views.

Zoom-w displays the view range of the selected window.

The third category is view translation. Pan and its branch commands.

I don't know whether you use the mouse to select the icon in the toolbar or use the keyboard to enter commands when you control the view. Think back to the past, in order to facilitate view control, transparent commands were often used. After AUTOCAD and pc mouse (middle button is the wheel) above version 00 appear, the zoom and translation of the view can basically meet the requirements by using the middle button.

Scrolling up and down with the middle mouse button is real-time zooming, and the middle mouse button is panning. And these are transparent commands, that is, commands that can be inserted in the process of other commands. Using pc mouse to control view, you must master it skillfully.

Now that the use of the mouse is mentioned, let's talk about the selection method of primitives which are also closely related to the mouse.

When we edit the command, it is inevitable to select the primitive. There are two common ways to edit commands and select entities. I'm used to the second one.

First, click or box the graphic elements with the mouse. At this point, the selected graphic element is highlighted. Then enter the edit command through the keyboard to operate. In this way, the Shift key can be used to remove redundant selected entities.

2. Enter the editing command with the keyboard first, then select the graphic element to be operated after confirmation, and then confirm the editing operation again after selecting the graphic element to be operated. In this way, I think it is more convenient and flexible to choose the elements to be operated, and you can use the auxiliary keys to help you choose.

P-previous, select the entity of the last operation.

R-remove, delete the selected element.

A-add, add the selection element (after using remove).

Both methods involve the same content related to the use of the mouse.

Left mouse button. The left mouse button is used to select an object.

One is to click on the graphic element directly.

Second, click the left mouse button, drag the mouse to the upper right or lower right, and then release it. At this time, the solid line selection box appears, and only entities completely within the solid line frame can be selected.

Third, after clicking the left mouse button, drag the mouse to the upper left or lower left, and then release it. At this time, a dotted line selection box appears, and you can select as long as some primitives are in the dotted line box.

Right mouse button.

The right mouse button also played a big role. We first need to change the system configuration of AUTOCAD. In the user system configuration, there is a "Custom Right Click" option. In default mode and edit mode, select to repeat the last command; In command mode, select OK.

The Enter key and space bar in the keyboard can also repeat the last command in "Default Mode" and "Edit Mode"; In command mode, confirm. But the speed is definitely slower than using the right mouse button to achieve the same goal. I suggest you give it a try and think it over.

Drawing and printing scale control, border application, size command.

After drawing drawings, we should print them out. Only by printing out the drawings (white drawings or blueprint for drying sulfuric acid paper) can we think that our drawing work is basically completed (and of course, sorting and filing, etc.). When printing, there is an unavoidable link, that is, the proportion problem. If the printing ratio and drawing ratio are reasonable, the final finished drawing will be clear and beautiful. We often see that some pictures are dense and some pictures are empty, which is improper scale control. So in terms of printing scale and drawing scale, what should we pay attention to when drawing and at the beginning of drawing?

Generally speaking, there are two kinds of drawings that we finally print out: proportional and non-proportional. Proportionally, it is generally a construction drawing; There are many situations that are out of proportion, such as scheme text, flow chart (seen by yourself), condition chart, etc. In recent years, the text of preliminary design (extended design) has gradually changed to A3 size printing.

Let's take a look at the construction drawings printed in proportion first. Construction drawings are basically drawn in proportion, but there will be different scale settings when drawing. For example, the horizontal section is generally 1: 100, the stairwell and bathroom are 1:50, the details of the node are 1:20, and the details of the node in the decoration drawing may be 1:/kloc-0 and/kloc-0. Next, I take a set of conventional construction drawings including vertical section, staircase, bathroom details and node details as an example.

First of all, we usually draw a plan at the beginning. At this time, we need to draw every standard unit in AUTOCAD 1 and every actual 1MM, and so do other vertical sections. There are two places to pay attention to at this time. First, all fonts should be set to a height of about 350, the room name can be slightly larger, and the height of special fonts such as drawing names should be set separately. 2. After dimensioning, set the "Global Scale of dimensioning" to 100 (I modified some contents in the previous dimensioning settings, please watch). Other settings, according to the above.

Next, the stair detail and bathroom detail with the scale of 1:50. When drawing this kind of picture, I usually copy the relevant parts of the plan to the original picture, and then delete the redundant parts and cut them out. Next, we need to modify something. First, the linear scale, except the solid line, everything such as dotted line and dotted line is changed to half of the original linear scale. Second, the scale of the same word size, elevation size and axis number is the original ratio of 0.5. Third, label setting, change the "label global scale" in all labels in this part to 50. In this case, when printing at the ratio of 1:50, the size of each part will be more appropriate.

The node details of 1:20 are drawn in the same way, so they are not repeated here.

After painting, all you have to do is set the frame. Every company has its own picture frame, and different pictures should have it. When making picture frames, most of them will be made according to the ratio of1:1:A0-1194 * 840; a 1—840 * 597； a2—597 * 420； a3—420 * 297； A4—297*2 10. Vertical frames are often used in tables A 1 and A2. Also, when we need to lengthen the picture frame, we should increase it in the direction of the long side of the picture frame according to the modulus of the long side of the picture frame 1/4. No matter how many sheets are printed in each frame, the size of the drawing column should be consistent when printing according to a certain proportion. We scale frames of different sizes according to the proportion we want to draw, and just put the pictures in.

There are still two points to be said about the scale of construction drawing. First, not all vertical sections should be based on the ratio of 1: 100. For some warehouses and factories without details, the ratio of 1: 150 or 1:200 can also be considered. Only in this way can the drawings be complete.

The second point is, no matter what kind of drawing, it must be remembered that every actual 1MM corresponds to every standard unit in AUTOCAD (except for general drawing), and the drawing at different scales is only marked with different font sizes, linear scales and global scales.

Of course, the above situation is for all maps with the same scale to be plotted in the same frame. When you want to put different scales in a photo frame, it's a little different. Let's take a plan of 1: 100 as an example.

First, make sure that 1: 100 is the main scale in this picture. The plan of 1: 100 is drawn according to the above method, and the detailed drawing of 1:20 is also drawn according to the above method, and all settings are modified. When it is found that the diagram of 1: 100 should be incorporated, copy the node of 1:20 into the diagram frame of 1: 100, and the Scale5 is 5 times, and then two things need to be modified. One is a linear ruler, and the other is two parameters in the label. One is to change the global scale to 1: 100 (main scale), and the other is to change the linear scale to 0.2. It doesn't matter. Of course, when drawing drawings with other scales, if you decide to put them together with other drawings with different scales at the beginning, you can adjust some of the above orders, which can reduce some steps and spend less time.

Drawings that are not drawn to scale also have some points to pay attention to, as well as the scale problem.

Let's take a scheme as an example.

When we are designing the scheme, we should pay attention to the proportion when it comes to sorting out the drawings. First, determine the final drawings. In the past, the text of the scheme was A3, but now A2 is commonly used (that is, two vertical versions spell A3). After determining the final plot ratio, it is necessary to estimate the approximate plot ratio, and then derive the appropriate values of font size and marking size in the drawing according to the printed word height of about 2.5MM (the proportion of text in the scheme is generally above 1:200, unless it is a villa, a small foreign house or a small public building). If necessary, you can print out the first similar drawing at the initial stage of sorting, and then continue to sort out and improve other drawings after confirming that there are no problems. After all the drawings are sorted out, set the frame and give it to the printing company-OK.

Here, there is a little space about paper. Drawing space is a very interesting thing, and the scale setting of drawings is quite different from that of batch print.

Interaction between AUTOCAD and other software, engaged in design work. Besides AUTOCAD, other softwares, such as Sketchup, Photoshop, Lightcape, 3dMax, CorelDraw, Word, Excel, etc. , often used, sometimes encounter the interaction of various software. In this part, I will talk about my experience in this field.