Index: trunk/src/obj_arc.c
===================================================================
--- trunk/src/obj_arc.c	(revision 27925)
+++ trunk/src/obj_arc.c	(revision 27926)
@@ -929,7 +929,7 @@
 {
 	pcb_coord_t thickness = arc->Thickness;
 
-	if (!arc->Thickness)
+	if (arc->Thickness < 0)
 		return;
 
 	if (delayed_terms_enabled && (arc->term != NULL)) {