Actually there are a couple of things that can be done.
The option that
jerry1423 mentioned will effect all solid and sheet bodies in your session, but it's not set in Customer defaults, but rather at...
Preferences -> Visualization -> Visual
...and in the section of the dialog labeled 'General Display Settings', sub-section 'Session Settings', you'll find the option 'Edge Emphasis'. Toggle it ON to get the effect that you're looking for. It will remain ON, from session to session, until you toggle it OFF.
The second approach is to actually edit the width of the edges of a body, but that's done on an body by body basis. To change this setting, go to...
Edit -> Object Display...
...and select the solid/sheet body and hit OK. When the dialog opens, in the section labeled 'Basic' you can select any of nine different edge 'Width'.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
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