Set pen widths by scale in Manage tab › Settings panel › Additional Settings › Line Weights. Assign pens to categories in Object Styles and to drawn lines in Line Styles. If every line looks the same on screen, turn off Thin Lines.
Or, just ask Mira, a free add-in, to bring a whole view onto your firm's weights.
How to do it in Revit
Step 1: Open the Line Weights dialog
Click Manage tab › Settings panel › Additional Settings › Line Weights.
Step 2: Set model pen widths by scale
On the Model Line Weights tab, each row is a pen (1 to 16) and each column is a view scale. Click a cell and type a width. A width applies to its scale and every larger scale until the next column, so a pen can print thinner on a 1/8" plan than on a 1/4" plan.
Step 3: Add a column for a missing scale
To control a scale that has no column, click Add and pick the scale. Without its own column, a view uses the nearest scale's widths.
Step 4: Set the annotation pens
On the Annotation Line Weights tab, set the pens for section lines, dimension lines and other annotation. These don't change with scale.
Step 5: Assign pens in Object Styles
Click OK, then open Manage tab › Settings panel › Object Styles. For each category, set the Projection and Cut pen. Some categories, such as furniture, have no cut value (Autodesk Help: Object Styles).
Step 6: Set the pens for line styles
For detail and model lines, open Manage tab › Settings panel › Additional Settings › Line Styles and set each style's pen.
Step 7: Check the result with Thin Lines off
Thin Lines (on the Quick Access Toolbar) draws every line at one thin width on screen, whatever its weight. It doesn't affect printing.
Autodesk's own walkthrough is in Specify Line Weights.
What to watch for
Line weight lives in four places. Most line weight problems come from fixing the right line in the wrong place. The Line Weights dialog sets the width of each pen number (model pens change with the view's scale; annotation pens don't). Object Styles sets which pen each category uses, for projection and for cut. Line Styles sets the pen for lines you draw yourself. Overrides change all of that for one view, one filter or one element: Visibility/Graphics (VG), view filters, and Override Graphics in View › By Element.
Fix it at the right level. Change the lowest setting that explains the problem. If every wall cut in every view is too heavy, that's Object Styles, not a VG override in each view. If one view needs lighter furniture, that's VG for that view. An element override is the last resort, because nobody can see it from the outside, and it beats everything below it: filters, the category settings in VG, and Object Styles.
Thin Lines is on. Everything looks the same weight on screen, so a heavy pen goes unnoticed until it prints.
The scale changed. The same pen number prints at a different width at a different scale. Check the column for the view's scale.
The detail came from another project. When a detail is inserted from another file, its view-level VG overrides and By Element overrides travel with it. Object Styles don't: they're a project setting, so the detail takes this project's weights. A detail that looked right in its old project can print differently here.
Near-duplicate line styles came along. Copied details bring their own styles: "Medium Lines (1)", "Solid_02", "Pen 2". Each one looks almost right.
One project's weights are easy to keep straight. The trouble is what arrives from elsewhere: details from a 2011 project, a consultant's drawing, a manufacturer's family. Each brings line styles, text types and fill patterns with names that almost match yours. Fixing them by hand means selecting lines, changing styles and checking prints, detail after detail, and the drift between projects keeps growing. The details stop matching the firm standards your template was built to hold.
Or, just ask Mira to do it.
Mira is an AI thinking partner for Revit that automates the work you repeat and builds tools your team needs.
- Type this in Mira
Change these section lines to our medium line weight.
Select the lines first. Mira makes the change and captures an after-screenshot so you can check it before you save.
How do I adjust line weights in Revit?
How do I display line weights in Revit?
How do I add line weights in Revit?
How do I turn off line weights in Revit?
Why do my lines print thicker than they look?
Try it yourself.
Or bring it to the firm.
The download is free and takes a minute. The firm conversation is where your standards, your library, and your rollout get built. Start wherever makes sense.