I'm not sure how to take a symbol which represents a overturned thrust fault from one AI file and apply it to a solid line in another file. If I create a new symbol from the pattern I want which has two teeth as shown in the attached picture, it only applies those two teeth to the whole line no matter how long it is. I would like the teeth pattern to repeat throughout the whole line if possible.
Use a custom brush.
- Take the artwork you want to repeat over the lines. In your case, the symbol. You can't use symbols in brushes though, so expand the symbol first.
- Drag the artwork to the Brushes panel (Window → Brushes) and from the New Brush dialog select "Scatter Brush" (You could use a pattern brush, but that will either stretch or leave spaces between the repeating artwork). Leave all the options at their default 0/100% since you don't actually want any variance.
- Apply your new brush to your lines. If you set a colorization method in the brush options you can even change the color by simply changing the stroke color.