Archive for the ‘Tutorial’ Category

AutoCAD Tutorial No. 02 [filter]

Friday, December 15th, 2006

This weeks tutorial will cover another little used command called Filter.

Filter: Creates a list of requirements that an object must meet to be included in a selection set

Filters can be a huge time saver and are extremely flexible to use. Let’s look at a very messy drawing situation. The following picture shows about 75 circles in 4 different colors and 3 different radii. We have red, white, yellow and red circles and radii of 22″, 23″ and 24″.

Now lets say you are asked to find and delete all circles that do not have a radius of 24″. In other words leave only the circles that have a radius of 24″. There are may ways to accomplish this, one is to individually select each circle, run the list command and either leave the circle or delete it. It will probably take 15-20 minutes to select all the circles using this method. There is also the probability that a circle will be missed.


A simpler solution is to use the filter command. Type filter or fi at the command line.


The filter dialogue box will appear. Pick the Select Filter pull down menu and select Circle Radius. The X filter box will now be active. Pull down the menu and select != (Not Equal To) and in the box next to it type in 24 for the radius. Now click on Add to List. The filter has now been added to the filter selection set list. You may have noticed that two items have been added, one look for all circle objects and two find all objects that have a circle radius NOT EQUAL to 24″. Next we will click on the Apply button, causing the dialogue box to dissapear.

Next window the entire group of circles. All circles that fit the filter criteria will now be highlighted. Type erase at the command line or hit the delete key.

All that is left are circle objects with a radius of 24″. The best part is it only took 30 second to to this and the chance of error has been eliminated.


Very specific filter sets can be created to locate just about anything in a drawing. Lets try one more lets eliminate all circle objects that are EITHER NOT 24″ in radius or are NOT yellow. In other words the only objects left are either 24″ in radius and any color or yellow and any radius.

Here is what remains. If you want to try this exercise you can download the AutoCAD file here. Try other combinations like find all blue circles with a radius less than or equal to 23″. Til next week happy filtering.

AutoCAD Tutorial No. 01 [extrim]

Wednesday, December 6th, 2006

I spend a great deal of my week showing / teaching fellow Architects and Engineers how to accomplish tasks and solve problems as they pertain to AutoCAD. Starting this today I will try to post a new AutoCAD tip or tutorial every week.
This weeks tutorial covers a little know and very useful command.

Extrim: Trims all objects at the cutting edge specified by a selected Polyline, Line, Circle, Arc, Ellipse, Text, mtext, or Attribute Definition.

This command was once part of the AutoCAD Express Tools and is now relegated to the command line in release 2007. What this command does is allow the trimming of all objects around a cutting edge with a single pick. It can trim a few objects or hundreds all with a single pick. It is a huge time saver, for example, when trimming around a building on a site plan.

Type some text or mtext and draw a bunch of lines, arcs, polylines, whatever, going thru the text object.


Here is some text with lines going thru it. Issue the extrim command and select the text object. A bounding box will appear around the cutting object.The object (text) will be highlighted. Next left mouse pick any point within the bounding box.

Here is the resulting text trimmed of all lines.

Here is another example: A building with polyline grade lines and some yellow straight lines.

Issue the extrim command and select the blue “building” outline as the cutting edge when prompted at the command line. Next you will be prompted to select the side to trim on.


Here is the result from picking a point outside the “building” boundary.


Here is the result from picking a point within the cutting boundary area.

Pretty cool!