About units

[helpme]

Hi everyone i still cant understand about the units

i open acad iso template to work in mm and the insertion scale is also showing in mm.what if i want to draw in meters or cm. iam so confused

[Tiger]

If you want to draw in meters, you change the Units to Meters (type UNITS to open the Units dialogue box) and then you draw in meters. Or change it to centimeters. Or whatever you like.

One thing to keep in mind though, is that if you change UNITS, that doesn't affect what you have aldready drawn. You can't use Units to scale your objects from millimeters to meters. The Units-command controls how AutoCAD scales content (blocks and externals references) that you insert in your drawing.

[ReMark]

Have you seen this tutorial re: Units and Scales?

http://www.cadtutor.net/tutorials/au...and-scales.php

The only way I know that you can specify the units (mm, cm or m) you are drawing in is via the -DWGUNITS command. There you can select from the three most common metric units (millimeters, centimeters and meters) as well as imperial units.

Type the command at the Command Line and follow the prompts. This is what you will see:

Drawing units:
1. Inches
2. Feet
3. Millimeters
4. Centimeters
5. Decimeters
6. Meters
Unit for length <3>: 4

Drawing unit display formats:
1. Scientific
2. Decimal
Linear display format <2>: accept the default

Linear display precision <4>: accept the default

Scale objects from other drawings upon insert? [Yes/No] <Yes>: accept the default

Match INSUNITS to drawing units? [Yes/No] <Yes>: accept the default


** WARNING: you have changed the unit for this drawing database. **
** All new objects will be drawn according to the new unit, but **
** existing objects will not change size unless you specifically **
** ask to have automatic scaling occur. **

Scale objects in current drawing to reflect change in units? [Yes/No] <Yes>: in an empty drawing this is of no consequence

[rkent]

If you are in a blank drawing then simply use UNITS command, set Length to Decimal. Now when you draw you will be thinking in mm or Meters, just as the tutorial talks about, see Remark's post with the link.

That is it, change to Decimal, draw in the unit you want. Enter 1 unit for a line length and it is a mm, or it can be 1 Meter, but not both in the same drawing. In a drawing assumed to be mm then if a meter is needed you will input 1000 in a command, if the unit is Meters then you will input 1 in a command for 1 meter.

Plot scales will be vastly different depending on which unit you are assuming for your drawing as title blocks in a layout will be in mm regardless of your model space assumed unit of mm or M.

Text height will be set depending on whether your drawing is mm or M, and whether or not you are using Annotative scaling. Ditto for dimstyles.