How To Draw Clean Polylines In Autocad

Topics covered in this Lesson:

Polylines - creating and editing, Revision Clouds

A polyline is an object in AutoCAD that consists of one or more line (or arc) segments. A rectangle is an example of a polyline that you lot are already familiar with. As you've seen, information technology is i object that can exist modified and worked with easier than iv dissever lines.

Polylines are created using the POLYLINE control, invoked by typing PL at the control line. To draw a simple polyline, draw it as though you are using the line control. The merely difference is that information technology is one object instead of many.

Polylines have some unique qualities that make them very useful:

They can have width (constant or varying)
They can consist of arcs and lines.
They can be edited
They tin be joined together.
They can be exploded into private segments

Control	Keystroke	Location	Result
Polyline	Pline / PL	Home > Draw > Polyline	Creates a polyline of arcs and/or lines.
Polyline Edit	Pedit / PE	Dwelling house >Change > Polyline Edit	Edits polyline objects
Explode	Explode / Exp	Dwelling > Modify > Explode	Separates objects into individual components
Revcloud	Revcloud	Home > Draw > Revcloud	Draws a (rectangular by default) Revcloud

When yous commencement the control, you will notice that in that location are several options bachelor:

Command: PL PLINE
Specify outset signal:
Current line-width is 0.0000
Specify adjacent signal or [Arc/Close/Halfwidth/Length/Undo/Width]:

Remember that any time y'all want to choose an option, you type in the Capitol letter of that selection.

Ane important tool is the Shut choice. This truly closes a polyline, which is different that but having two ends meeting at the aforementioned point - it'southward like welding the ends together. A closed polyline is required for extruding into 3-D space and other modifications. If you use the C option while drawing to complete your polyline, it will automatically be closed.

The Spline option allows you to draw a shape of lines using arcs and/or directly lines and and so change them into 1 flowing curve. (Spline is besides a carve up command on its own.)

Likewise by changing the Width of a polyline, yous tin get some different looks to your lines. This is one way you can describe an arrow in AutoCAD:

Command: PL PLINE
Specify beginning indicate: <Choice Beginning Point>
Current line-width is 0.0000
Specify next signal or [Arc/Halfwidth/Length/Disengage/Width]: Westward
Specify starting width <0.0000>: 1
Specify ending width <1.0000>: <ENTER>
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: <PICK 2nd POINT>
Specify next betoken or [Arc/Close/Halfwidth/Length/Undo/Width]: Due west
Specify starting width <1.0000>: 4
Specify ending width <4.0000>: 0
Specify adjacent signal or [Arc/Close/Halfwidth/Length/Undo/Width]: <Selection 3rd POINT>
Specify next bespeak or [Arc/Close/Halfwidth/Length/Undo/Width]: <PICK FOURTH POINT>

Depending upon the length of your lines, yous may finish upward with a polyline that looks like this:

Polyline Arrow in AutoCAD

Look at the examples below and then practice drawing polylines and try some of the options available.

Polyline Samples

Below is a sample drawing you tin reproduce using a polyline (it could represent a slot to be cut out with a CNC router. Showtime, call up about how you would draw information technology using lines, arcs and circles.

Polyline Slot

Hither's how you describe it using one polyline:

Remember DDE? Starting time by entering your get-go point, and then (with Ortho or Polar on) move your cursor to the right and type v <ENTER> so A <ENTER> for arc and move your cursor upward and type 2 <ENTER> and so type L <ENTER> (to get back to direct lines) and more your cursor to the left and type five <ENTER> then back to arc (A <ENTER>) and so blazon CL to close the polyline. Wow! That was easy!

Control: PL PLINE
Specify offset point: <pick a point>
Current line-width is 0.0000
Specify next bespeak or [Arc/Halfwidth/Length/Disengage/Width]: 5
Specify adjacent betoken or [Arc/Close/Halfwidth/Length/Undo/Width]: A
Specify endpoint of arc or
[Bending/CEnter/Close/Direction/Halfwidth/Line/Radius/Second pt/Disengage/Width]: 2
Specify endpoint of arc or
[Angle/CEnter/Close/Direction/Halfwidth/Line/Radius/Second pt/Disengage/Width]: Fifty
Specify side by side point or [Arc/Close/Halfwidth/Length/Undo/Width]: 5
Specify next point or [Arc/Close/Halfwidth/Length/Disengage/Width]: A
Specify endpoint of arc or
[Angle/Centre/Shut/Management/Halfwidth/Line/Radius/Second pt/Undo/Width]: CL

To edit a polyline, use the PEDIT control or blazon PE at the command line.

Command: PE
PEDIT Select polyline or [Multiple]: <SELECT A POLYLINE>
Enter an option [Close/Join/Width/Edit vertex / Fit/ Spline/ Decurve/ Ltype gen/Undo]:

One of the most common editing tools is the Join (J) choice. Use this to combine two or more polylines and their endpoints.

Utilize the LINE command to draw a line from 0,0 to v,5. Now use the line command to describe a line from 5,5 to 8,five. This volition get out you with ii line objects that share a common betoken (5,5). Commencement the PEDIT command (PE) and select one of the lines. AutoCAD will ask you if you want to turn it into ane, select Y <ENTER>.

Command: PE PEDIT Select polyline or [Multiple]:
Object selected is not a polyline
Do y'all want to plough it into ane? <ENTER>
Enter an option [Shut/Join/Width/Edit vertex/ Fit/Spline/ Decurve/ Ltype gen/Undo]: J
Select objects: <select a line> 1 institute
Select objects: <select the other line>
ane segments added to polyline
Enter an selection [Close/Bring together/Width/Edit vertex/ Fit/Spline/ Decurve/Ltype gen/Undo]:<ENTER>

Now you lot accept one object (a polyline). This is a handy tool to use for editing. Now the shape is complete and you can offset information technology, scale it, etc., as i object. In 3D, you could also extrude it (if it is closed).

Once y'all accept a polyline, it is sometimes useful to interruption it into the individual segment. For instance, you might want to first segments past varying distances.. To do this, use the Explode command. Information technology is used to divide many other AutoCAD objects besides such as blocks.

Polylines are useful - try to utilize them whenever possible. Sometimes you tin can draw the outside walls of a edifice, kickoff the polyline for the wall thickness, and then explode both of them for more versatility.

Video: Polylines in AutoCAD

Revcloud (Revision Cloud)

Another unlike version of the Polyline control is Revcloud (Revision Deject) control. This is something yous don't want to come across on your drawings when the boss reviews your work. A Revcloud is used to highlight problems, revisions or errors in a cartoon.

Revcloud Example

Y'all might likewise desire to create a Revcloud to highlight a question y'all take with your own work.
To create a Revcloud, start the control. Then set the arc length to about 12 for an architectural drawing, or test out different arc lengths.

Control: REVCLOUD
Minimum arc length: 8.0000 Maximum arc length: eight.0000 Manner: Normal Type: Rectangular
Specify first corner signal or [Arc length/Object/Rectangular/Polygonal/Freehand/Fashion/Modify] <Object>: A <ENTER> Specify minimum length of arc <8.0000>: iv <ENTER>
Specify maximum length of arc <4.0000>: <ENTER>
Specify start corner point or [Arc length/Object/Rectangular/Polygonal/Freehand/Style/Change] <Object>: <Selection FIRST CORNER>
Specify opposite corner: <Option SECOND CORNER>

You might have concluded up with something like this:

Revcloud with Arc Length of 4 units

One thing with revclouds is that information technology can exist hard to define a specific area conspicuously. Therefore, y'all have another option for creating authentic, clean revclouds like the i in the first case. Start by cartoon a polyline over the area you want to highlight, then start the Revcloud command and choose the Object option. Select the polyline and press enter to end the control. This will work on nearly AutoCAD objects.

Video: Revclouds in AutoCAD

Extra Practice: Re-create this cartoon - extra_2-001.gif. You lot will demand to utilise the Arc option when cartoon the polyline. Try to draw information technology as one line, but if you have trouble, describe ii polylines and bring together them. After drawing information technology, employ the Spline pick of PEDIT to modify the polyline. Once yous have the spline, utilise the Decurve option.

Extra Practise: Depict the exercise from Lesson 1-4 equally a polyline. This is also a good chance to review your input options.

Extra Practise: Copy this drawing - extra_2-002.gif. The center line in the middle indicates that both halves are the same. Create ane polyline, so outset it to get the smaller one.