OK guys, I finally was able to talk to the friend and ex-neighbor that gave me the PC with the AutoCAD LT on it. I told him I found the AutoCAD and tried to use it but was having problems.  His first words were "Oops, I meant to uninstall that program".  He said that he quit using it because he also started having problems using it.  He said that as soon as he got everything unpacked in his new house, he would find the install disk and mail it to me.  He felt sure that a reinstall would fix it. He just never had time to do it.

In the mean time, I pulled out an old copy of MicroStation V8 XM that I had from before I retired.  It installed fine, but I didn't have a license for it and it would only run for 30 min and then shut down. So, I called a good friend at the company I used to work for. I knew that they had more licenses than they needed so he checked-out a license for me to use for a while and emailed it to me - I think it's good for a couple of years.

I did have some training and a a few years using using MicroStation before I retired so it's all coming back to me as I use it.  MicroStation, IMO, is a much more intuitive program and the more I doodle with it, the easier it is to use.  So, I don't think I'll have a need for the AutoCAD LT on the PC and will probably uninstall it.

Thanks for trying to help but it seems like the problem I was having wes due to a broken AutoCAD LT and not my inexperience with it.

John Connor wrote: Drawing the 12x9 using the Rectangle command > Dimension option would be much easier and there would be no trimming involved.

True, but I wasn't trying to teach Ted how to draw a rectangle. I was using a rectilinear task as an example of how to perform basic Cartesian coordinate entry in some simple AutoCAD commands.

Teach a man to draw a rectangle, he can only draw rectangles. Teach him how to enter coordinates, he can draw any damn thing in the universe. Fish, day. Catch, life. As it were.

KegTed wrote: Hi Folks, I'm a retired "t-square and triangle" drafter and I'm trying to learn something new in my old age.  A neighbor friend (a retired engineer) gave me a PC that has AutoCAD LT 2013 installed on it. I wanted to try drawing  the floor plan of the townhouse that my wife and I live in.  After a lot of fiddling around, I found the line drawing tool.  But every time I begin to draw a line by picking the first point with the mouse, the display and input switches to what I'd call 'Polar Coordinates'.  In other words, it prompts for distance and angle for the second point.  That type of input is completely foreign to me. How can I switch the input method to to 'Rectangular (x, y) coordinate' input?

Ted,

This is Basic AutoCAD. Since you're new to the program, you'll need to start at the very beginning.

Cartesian (i.e. X,Y,Z) coordinates can always be entered on the command line when Acad asks you for a point, a distance, or an angle. Cartesian coordinates work just like a sheet of graph paper; the bottom line of the grid is the X axis, which is numbered from left to right, and the left line of the grid is the Y axis, which is numbered from bottom to top. Coordinates are always measured from the axes - X first (distance from the 0 in a horizontal direction), then Y (distance form the 0 in a vertical direction). The point where the X and Y axis cross each other is called the 0,0 origin point. In CAD circles, it's usually just called 0,0.

Cartesian coordinates in Acad operate in two 'modes', Absolute, and Relative. Absolute coordinates are always measured from the 0,0 origin point, but Relative coordinates are measured from the last point you entered or clicked. Positive numbers always count to the right in the X direction, and up in the Y direction, while negative numbers draw to the left in the X direction and down in the Y direction.

If you start the Line command and type in "2,1", the first point of the line will be 2 units to the right of the 0,0 origin, and 1 unit up from the 0,0 origin. This is an Absolute coordinate.

Relative coordinates are entered by putting the @ symbol in front of the number when you type them in. So, when Acad asks you for the next point point, and you type in "@12,9", the line will be drawn 12 units to the right of the first point, and 9 units up from the first point. If you enter "@6,4" for the next point, the resulting line will be drawn 6 units over and 4 units up from the *previous point*, not from the first point or from the origin. Relative coordinates are always measured from the *last point you entered.*

Quick exercise:
To draw a rectangle that's 12x9, start the Line command, pick a random point for the first point, then type:
@12,0 <<draws a horizontal line 12 units long, 0 units tall, left to right>>
@0,9 <<draws a vertical line 0 units long, 9 units tall,bottom to top>>
@-12,0 <<draws another horizontal line 12 units long, 0 units tall, but it draws from right to left because of the - sign>>
@0,-9 <<draws another vertical line 0 units long, 12 units tall, but draws it from top to bottom because of the - sign>>

Another basic construction method in Acad is to draw horizontal and vertical lines using Ortho mode (toggle it on/off at the bottom left  of the Acad window or by using Function key F8 on your keyboard), then using the Offset command to create parallel copies of these lines at set distance.

Draw a horizontal line.
Draw a vertical line that overlaps the horizontal line slightly
Click the Offset command from the Modify panel of the Home ribbon tab
When asked for an offset distance, enter 9
Click the horizontal line, then choose which side you want it to copy to <<a parallel copy of the line is created, 9 units away from the original, on the side you chose>>
Exit the Offset command
Restart the Offset command
When asked for an offset distance, enter 12
Click the vertical line, then choose which side you want it to copy to <<a parallel copy of the line is created, 12 units away from the original, on the side you chose>>
Exit the Offset command

Now you have a 12x9 rectangle, but the ends overlap. Use the Trim command to trim off the excess.

There are easier and quicker ways to do these things, but the preceding examples are meant to teach you basic methods of entering coordinates and distances into AutoCAD. These techniques are the basics that you need to construct simple, orthagonal room layouts.*

Bonus exercise:
*After you have created the outline of the room, try using the Offset and Trim commands to create an outer boundary representing the wall thickness, using a .5 unit offset distance.

Happy CADing.


Edited by TheWillCAD - 10.Jul.2015 at 18:51

John Connor wrote: You're making this more frustrating than it needs to be. How would you have drawn the same line if you were still doing it manually on a drafting board?  Come on...think. By the way, the line would be 2.2361 in length, drawn at an angle of 26.5651.

(Thinking......)
Doing it manually, I would have drawn a vertical construction line 2" to the right and a horizontal construction line 1" to the top.  The intersection would be the endpoint for the line.

I was hoping that I could do that with AutoCAD LT by dragging the cursor to the right and keying in 2' and then move the cursor to the top and key in 1" and then click to accept the point but that does not work.

Thanks.

John Connor wrote: Well that image would have been best included in your very first post.  All the while I thought you were talking about the coordinates that are displayed in the lower left hand corner of the screen.  Seems you were referring to Dynamic Input which is what you see near your crosshairs.  Disable the feature.  There is an icon on the System Tray at the bottom of your screen to do so.

Hi John, I really appreciate the help that you've given me. I disabled the Dynamic input as you suggested but it still wanted me to input a line by distance and angle.

I just want to draw an object by starting in the lower-left corner.  The first segment is 5" long to the right, next segment is at an angle 2" to the right and 1" to the top - I do not know the angle in degrees.  It's hard (for me) to believe that there's not an easy way to toggle between polar and rectangular input.

When I discovered this AutoCAD LT 2013 on the PC my friend gave me I thought WOW, this is something I can use to kill time and maybe make a useful sketch every now and then.  But it's turning out to be more frustrating than relaxing.    I think I'll just put this AutoCAD LT thing back in the box and for get it.

Thanks again for trying to help.