Marcel Aubin has been using AutoCAD since release 1.4 and wants to share with us a tip that he finds very useful.
"This simple tip relies on the .X, .Y, .Z, .XY, .XZ, and .YZ filters. I'll give a few examples to illustrate their usefulness.
"Example 1: I want to put text in the exact center of a box. I call up the Text command, use the C justify mode, and type in .X. Then I click the center of the base of the box Osnap using the middle Osnap. AutoCAD picks up only the x value of the coordinate and prompts me that it needs y and z, so I click the middle of one side of the rectangle and AutoCAD picks up the y and z values from the side's coordinate. It then assembles those values into a point, which is in the exact center of the box.
"Example 2: I want to move an object in the z direction. I start the Move command, select the object, and when asked for a source point I pick a specific point (using Osnaps). Thereafter, when prompted for the destination point, I first type .XY and pick the exact same point. But since I've used the .XY filter, AutoCAD then wants a value for z; just type it in."
Notes from Cadalyst Tip Patrol: This is a great tip that can help you draw more accurately. Here's the concept: when you create any type of object, you place that object in an x,y,z coordinate system. These filters will make certain that you are using specific values in any axis by copying that value from a preexisting object. You can use these filters to find intersects of lines, to make an object co-linear, or to help when drawing in 3D.