Stretch an image in AutoCAD. Stretch objects using the Extend tool
Computer-aided design systems - CAD
Working in AutoCAD
Self-instruction manual
2.3.2. Stretch objects using the Extend tool
Tool Lengthen is designed to extend lines until they intersect with other lines or drawing objects, which are called bounding edges. This tool has a somewhat unusual logic, but with practice its use becomes almost automatic and will not cause you any difficulties. Tool Lengthen is applied in two stages: first, the bounding edge is selected, and then the lines are selected that should be stretched to intersect with it (this is the unusual logic of this tool - most other AutoCAD tools suggest first selecting the object on which the operation will be performed). The selection of the bounding edge is completed by pressing Enter.
Rice. 2.17 Side walls of the cabinet after pairing
1. Launch the tool Lengthen by clicking on the button Lengthen panels Change or by selecting the command from the menu Edit » Lengthen or by entering the command in the command window Lengthen or simply U. In the command window, AutoCAD will prompt you to select bounding edges.
2. Select the topmost horizontal line (Fig. 2.18) and press Enter.
Rice. 2.18 Selecting the top line as a bounding edge
Advice. In the vast majority of cases, selecting objects in AutoCAD is completed by pressing Enter, no matter how many objects you select - one or a hundred. Therefore, you will have to remember that to continue with the command that asks you to select objects, you must complete the selection by pressing Enter.
3. Select two vertical lines indicating the inner contours of the side walls of the cabinet. Keep in mind that if you click at the bottom of the lines, AutoCAD will ignore the selection. Therefore, click at the top of the lines, near the bounding edge. Immediately after clicking, the lines will extend until they intersect with the bounding edge. Press Enter to complete the command Lengthen(Fig. 2.19).
Rice. 2.19 Internal vertical lines of the side walls are extended until they intersect with the bounding rib
We started the 2D modeling section and learned methods for creating 2D primitives. In order to create more complex graphic objects, you need to be able to edit flat objects. This lesson is devoted to a direct study of the issue of editing 2D primitives.
Editing objects provides the ability to delete, copy, move objects, change their properties such as color, line weight, line type and a number of other properties. You can perform operations on objects such as lengthening, cutting, mirroring, rotating by a given angle, etc.
Editing commands are accessed through:
1. Menu item Modify.
2. Toolbars Modify.
3. Entering a command from the keyboard.
Editing commands
Properties Command
Command entry methods:
- Type the command from the keyboard: .
- Menu call: Modify? .
- Double-click the left mouse button on the object.
- From the object's context menu, select the command.
With this command you can change the properties of one object or the general properties of several selected objects. The command opens a dialog box, the top line of which contains a list of favorite objects and buttons:
The window is divided into two columns. The first column contains the name of the property, and the second column contains the value of the property that can be changed.
ERASE Command
Command entry methods:
You can select objects before entering a command or after entering a command. In the first case, after entering the command, the selected objects are deleted. In the second case, the system prompts you to select objects.
The following dialog appears on the command line:
Command: _erase
Select objects: 1 found
Select objects: 1 found, 2 total
Select objects: 1 found, 3 total
Select objects:
After selecting objects, press the key Enter. The objects will be deleted. If it is necessary to delete an object not completely, but only a certain part of it, then use the commands TRIM (Crop) And BREAK (Break).
BREAK command
Command entry methods:
The command removes part of an object between two specified points. Using the command allows you to break a graphic primitive, such as a line or arc, into two objects. When deleting part of a line or arc, the first point on the object is specified, and the second is a point outside the end to be deleted. For a circle, the part that is removed is specified by two points in a counterclockwise direction.
After entering the command, the system issues the following requests:
Objects are selected after entering the command.
TRIM Command
Command entry methods:
The command cuts the selected object with a cutting edge that intersects it, and can be an arc, line, polyline, etc. After entering the command, one is first specified or several cutting edges are selected sequentially. The selection process is completed by pressing the key Enter. Next, the system will prompt you to select the objects that are cropped. It is necessary to indicate the part of the object that is cut off. To complete the selection, press the key Enter.
Working with the team is accompanied by requests:
EXTEND command
Command entry methods:
The command extends graphic primitives (line, arc, polyline, ray, spline) to the points of intersection with other objects, which will be the limiting edges. In its action it is the opposite of the command TRIM. After entering the command, requests for selecting limit edges are issued. You can stop selection by pressing the key Enter. Next, the system issues a request to select the objects that need to be renewed. The selection is completed by pressing the key Enter. When specifying objects, you must show the edge that is closest to the limit edge, otherwise the command will not execute.
System prompts will look like this:
| Command: _extend | Extend command. |
| Current settings: Project i on = UCS, Edge = NoneSelect boundary edges... | |
| Select objects: 1 found | Show limit edge |
| Select objects: | Click ENTER |
| : | Select objects that elongate |
| Select object to extend or shift-select to trim or: | Click ENTER |
MOVE Command
Command entry methods:
To move, you need to specify a base point on the selected object and specify the coordinates of the new position of the base point after moving the object. Coordinates are specified in any of the ways.
When using the command, maintain a dialogue:
| Command: move | Move command. |
| Select objects: 1 found | Select object |
| Select objects: | Click Enter. |
| Specify a base point. | |
| Set the coordinates for the new position of the base point. |
COPY Command
Command entry methods:
Copying objects is carried out in the same way as moving them. The difference is that a copy of the object is created at a given position while preserving the original.
ROTATE command
Command entry methods:
The command rotates an object at a specified angle relative to the base point (the center of rotation). The angle value is considered positive when turning in a counterclockwise direction. The base point can be selected when Object Snap mode is enabled.
Dialogue with the system:
| Command: rotate | Rotate command. |
| ANGDIR = counterclockwiseANGBASE = 0 | ANGDIR= counterclockwise. |
| Select objects: 1 found | Select an object. |
| Select objects: | Click Enter. |
| Specify base point: | |
| Specify rotation angle or : 30 | Set the angle value in degrees. |
Parameter Reference— (reference angle) allows you to set the vector and the rotation angle of this vector. The position of the vector after rotation specifies the new position of the object.
When selecting an option, maintain the dialogue:
| Command: rotate | Rotate command. |
| Current positive angle in UCS:ANGDIR = counterclockwiseANGBASE = 0 | The system displays the current angle value parameters: ANGDIR= counterclockwise. |
| Select objects: 1 found | Select an object. |
| Select objects: | Click Enter. |
| Specify base point: | Specify a base point—the center of rotation. |
| Specify rotation angle or R | Parameter selection Reference |
| Specify the reference angle<0>: | Specify the first point of the vector (point 1). |
| Specify second point: | Specify the second point of the vector (point 2). |
| Specify the new angle: 50 | Enter the angle value. |
MIRROR command
Command entry methods:
The command produces a mirror image of an object while maintaining or deleting the original object. After selecting objects, you need to specify the axis relative to which the mirror image is formed.
Dialogue with the system:
| Command: _mirror | Team Mirror. |
| Select objects: 1 found | Select an object. |
| Select objects: | Press Enter. |
| Specify first point of mirror line: | Specify the first axis point. |
| Specify second point of mirror line: | Specify second axis point |
| Delete source objects? |
Request to delete the original object |
SCALE command
Command entry methods:
Proportional increase or decrease in size of an object or group of objects relative to a given base point. To enlarge objects, set a coefficient greater than one. To reduce objects, the coefficient has a value less than one.
Hints provided by the system:
You can set the scale factor interactively. After selecting a base point, a rubber thread stretches from it to the intersection. By increasing or decreasing its size, you can set the coefficient value.
Option Reference(Reference Line) allows you to set the scaling factor by entering the original length of the line and its new length. The coefficient is calculated as the ratio of the second number to the first. The length of the segment can be determined automatically as the distance between two points specified with the cursor.
Use the command to enlarge the object by 8/5 times.
The dialogue with the system will look like:
STRETCH command
Command entry methods:
The command is used to stretch or, conversely, compress graphic primitives by changing the position of their limit points. When you apply a command to an arc, its radius changes. Selection of objects is carried out only by a secant frame or secant polygon. The command is not intended for working with circles, text, or blocks. Applying a command to a set of objects makes it possible to change them without breaking the relationship between the objects.
Working with the team is accompanied by dialogue:
Select objects: Click Enter. Specify base point or displacement: Select a base point. Specify second point of displacement or
The command changes the position of only those points that fall within the cutting frame. The position of the remaining points remains unchanged.
LENGTHEN Command
Command entry methods:
The command is used to change the length of a segment or arc. To change the length of a segment, you need to enter an increment value, a positive value if the length is increasing and a negative value if the length is decreasing. To change the size of the arc, specify the increment value of the internal angle, positive if the size is increased and negative if the size is decreased.
Command options:
DElta— the value of the length increase.
Percent— the value of increasing or decreasing the length of a segment or arc is set as a percentage of the current value to the new one. If a value greater than 100% is specified, the length increases. If the set value is less than 100%, the length is reduced.
Total— allows you to specify the new full length of the object. For an arc, you can specify a new internal angle value.
Dynamic— length changes dynamically using the cursor.
OFFSET (Similarity) Command
Command entry methods:
The command is intended for constructing primitives similar to those existing in the drawing. A similar object will be built at a given distance and in a given position relative to the existing one (mode offset distance). You can also construct a similar object passing through a given point (select the option Through). For a line, a line parallel to it is constructed. Similar to a circle is a concentric circle. A similar arc is a concentric arc with the same internal angle. For a polyline, a similar polyline is constructed.
Dialogue with the system:
Select the next object for which a similar one with the same value is built, or press the key ENTER to exit the mode.
To select a point through which a similar object will pass, maintain the dialogue:
FILLET command
Command entry methods:
The command is designed to pair two graphic primitives, namely: arcs, segments, polylines, with an arc of a given radius; allows you to round corners and can also be used instead of commands TRIM And EXTEND at zero radius value. When connecting two parallel segments, the radius is determined automatically as half the distance between the segments.
Command options:
Polyline— selecting this option serves as an indication to perform roundings along all vertices of the polyline with an arc of a given radius. The radius value must be set in advance. The system issues a request - Select 2D polyline: in response to which you need to select a polyline.
Radius— the value of the radius of curvature is set in response to a system request — Specify fillet radius< 0.0000 >: 20
Trim- allowed ( Trim default) or disabled ( No trim) trim the segments when rounding.
mUltiple— repeated pairing while working with one command.
Example of dialogue with the system:
| Command: _fillet | Pairing command. |
| Current settings: Mode = NOTRIM,Radi us = 0.0000 | Displays default parameter values. |
| Select first object or: R | Parameter selection Radius. |
| Specifyradius <0.0000>: 70 | Set the radius value. |
| Select first object or:P | Parameter selection Polyline for rounding all corners |
| Select 2D polyline: | Select polyline. |
Command CHAMFER (Chamfer)
Command entry methods:
A chamfer is a cut corner. You can create a chamfer using two methods:
1. Set the chamfer size - the distance from the vertex of the corner on each side.
The system will display a dialog:
| Command: _chamfer | Team Fasca. |
| 0.0000 | |
| Select first line or:d | Select option Distance. |
| Specifyfirstchamferdistance <0.0000>: 30 | Set the first distance value. |
| Specify second chamfer distance<30.0000>: 30 | Set the second distance value. |
| Select first line or | Select side one. |
| Select second line: | Choose the other side. |
2. Set the value of the chamfer size along the first side and the value of the angle in degrees relative to the first selected segment.
For this method, the system dialog will be like this:
| Command: _chamfer | Team Fasca. |
| (TRIM mode) Current chamfer Dist1 = 0.0000, Di st2 =0.0000 | Default parameter values. |
| Select first line or:a | Select option Angle. |
| Specify chamfer length on the first line<0.0000>: 40 | Set the distance value. |
| Specify chamfer angle from the first line<0>: 75 | Set the angle value. |
| Select first line or | Select side one. |
| Select second line: | Choose the other side. |
Command options:
Polyline - used to create a chamfer at all vertices of a polyline at once.
distance — the chamfer size is set on each side.
Angle - the size of the chamfer along the first and side and the value of the angle relative to the first segment are specified.
Trim- in mode Trim(default) lines are cut off. With a zero sense of distance, you can set the cutting of lines that intersect. No Trim— the chamfer is created without trimming. When the distance value is zero, lines that do not have common points are extended to the point of intersection.
Method - finding out which method is active Distance or Angle.
mUltiple — multiple construction of a chamfer while working with one command CHAMFER.
This completes our introduction to the commands for editing flat objects. And in the next lesson we will study shading.
We continue to study the possibilities of editing AutoCAD. Stretch in AutoCAD is as easy as rotating or scaling an image. Stretching allows you to very quickly change the length and height of an object while maintaining other dimensions.
The Stretch command is included in the editing block. Let's choose.
The stretching operation has one very important point, namely the selection of objects. After the program prompts you to select objects, do not rush. You need to select with a frame from right to left, starting from the free area of the drawing. Only this way, and not otherwise.
The most important point: The segments that are completely within the frame will simply be moved, and the segments that are partially within the frame will be stretched. After selection, it is allowed to exclude lines from the selected area; adding them is not allowed. Press "Enter".
Select the base point, then use the mouse cursor to set the direction of stretching and enter a numerical value. The picture shows what a fragment of the drawing looked like before stretching and what it will look like after. You can also see in the picture which segments are stretched and which are simply moved. As I wrote above, those segments that are not completely included in the frame are stretched.
I'll show you what the operation will look like if you select all the segments manually, or if all the segments fall entirely within the selection frame.
Moving occurs with copying, but the segments are not stretched. This is the most common mistake. At the same time, the segments that were selected remain in their places. Beginners begin to delete them and extend lines manually, but this is not productive and incorrect. The same situation will arise if, after selecting with a frame, you try to add a segment manually.
We looked at how to stretch an object in AutoCAD. It is worth noting that you can stretch both horizontally and vertically, and at a certain angle. The operation allows you not only to increase the length or height of an element, but also to reduce it. One more subtlety: the hatching of the cut that falls into the stretching area must be done separately from the rest of the hatching, otherwise all the hatching of the drawing will move. I talked about how to do it in one of the previous lessons.
Do you have any questions or is something unclear? — I suggest using the comment form and asking your question there.