Frequent tipster Danny Korem explains the AutoCAD settings that can help you display your linetypes properly, regardless of scale.
"Do you want your layouts with viewports to look good, no matter what the scale is? Sometimes it's confusing to output your linework in several scales side-by-side — and it might become frustrating. In addition, while you are doing this, the clock is ticking.
"As with many other things, the feature you need is pretty well hidden within AutoCAD. In the Home ribbon, Properties panel, in the linetype list, click Other and you are halfway there. When accessing the Linetype Manager dialog box, note the four buttons in the upper right; click Show Details. If PSLTSCALE is set to 1 or checked (as in the screenshot below), LTSCALE is governed by the viewport scale. If not, the viewports will reflect the general linetype, as in the case of model space. In such a case it won't look uniform in different scales in layouts with multi-scaled viewports.
"The factors at the lower right behave as if you went to the Properties palette and set a number as a default for your future linework."
Notes from Cadalyst Tip Reviewer Brian Benton: Before paper space (yes, that long ago) there was only one view to worry about: model space. It was easy; set LTSCALE once and you were good. With multiple layout tabs, however, one may wonder what to set the LTSCALE to. The answer is simple — you don’t have to set it to anything. Set LTSCALE to 1 and set PSLTSCALE to 1 (or On); this will allow AutoCAD to do its magic behind the scenes and adjust the linetypes according to the scale of the viewport. Once again, AutoCAD does the work for you.