Convert Drawings Between CTB and STB

If you’ve ever gone to print a drawing and saw CTB files in the Plot dialog when you expected STB, or vice versa, then this post is for you.

AutoCAD LT drawings can only use one kind of plot style table at a time – you have to choose between named styles and color-dependent styles.

Switching from STB to CTB is very straightforward. Simply run the command CONVERTPSTYLES, acknowledge the warning (“Yes, I really want to do this.”), and you’re done.

Going the other way, however, is a little trickier. Before you can use CONVERTPSTYLES to change a drawing from CTB to STB, you first need to convert the appropriate CTB file with the CONVERTCTB command.

If it’s successful, you’ll see this alert:

Then you can run CONVERTPSTYLES to change over your drawing. This time, though, there’s one more step to take – selecting an STB file.

Here’s where the tricky bit comes in: you *must* choose an STB file that was converted from a CTB file. You can’t use any of the out-of-the-box STB files that ship with AutoCAD LT, or any that you created yourself from scratch. If you try, you’ll see something like this:

For this reason, I tend to think of CONVERTPSTYLES as a temporary solution – for drawings you receive from clients, for example – rather than a permanent one.

If you want to change your workflow to always use STB files instead of CTB, I’d start from scratch with an STB template file (several are included with your AutoCAD LT installation).

Comments

[Bryan]

This is a great tip. Much easier to convert pen styles than I had expected within LT.