diff --git a/src/app/commands.rs b/src/app/commands.rs
index b5d720431..6310bc89d 100644
--- a/src/app/commands.rs
+++ b/src/app/commands.rs
@@ -3700,6 +3700,20 @@ impl H7CAD {
                             "UCSICON {sub}: updated {count} viewport(s) + model space."
                         ));
                     }
+                    "" => {
+                        // Bare UCSICON toggles visibility.
+                        self.push_undo_snapshot(i, "UCSICON");
+                        let visible = !self.show_ucs_icon;
+                        self.show_ucs_icon = visible;
+                        for entity in self.tabs[i].scene.document.entities_mut() {
+                            if let acadrust::EntityType::Viewport(vp) = entity {
+                                vp.status.ucs_icon_visible = visible;
+                            }
+                        }
+                        self.tabs[i].dirty = true;
+                        let state = if visible { "ON" } else { "OFF" };
+                        self.command_line.push_output(&format!("UCSICON {state}"));
+                    }
                     _ => {
                         self.command_line.push_info("Usage: UCSICON ON | OFF | NOORIGIN | ORIGIN");
                     }
diff --git a/src/app/view.rs b/src/app/view.rs
index 9001af89d..643a05fdc 100644
--- a/src/app/view.rs
+++ b/src/app/view.rs
@@ -108,7 +108,7 @@ impl H7CAD {
         let viewport_3d: Element<'_, Message> = if is_paper {
             paper_canvas_view(tab)
         } else {
-            shader(ViewportPane::model(&tab.scene))
+            shader(ViewportPane::model(&tab.scene, self.show_viewcube))
                 .width(Fill)
                 .height(Fill)
                 .into()
diff --git a/src/scene/render.rs b/src/scene/render.rs
index 56c6bce90..3e6c4d4bf 100644
--- a/src/scene/render.rs
+++ b/src/scene/render.rs
@@ -88,6 +88,7 @@ pub struct Primitive {
     pub(super) hover_region: Option<usize>,
     /// Background color used to clear the MSAA buffer at the start of each frame.
     pub(super) bg_color: [f32; 4],
+    pub(super) show_viewcube: bool,
 }
 
 // ── shader::Primitive impl ────────────────────────────────────────────────
@@ -120,13 +121,15 @@ impl shader::Primitive for Primitive {
         pipeline.upload_images(device, queue, &self.images);
         pipeline.upload_meshes(device, &self.meshes);
         pipeline.upload_wires(device, &self.wires);
-        pipeline.viewcube.upload(
-            queue,
-            self.cam_rotation,
-            bounds.width as u32,
-            bounds.height as u32,
-            self.hover_region,
-        );
+        if self.show_viewcube {
+            pipeline.viewcube.upload(
+                queue,
+                self.cam_rotation,
+                bounds.width as u32,
+                bounds.height as u32,
+                self.hover_region,
+            );
+        }
     }
 
     fn render(
@@ -137,7 +140,9 @@ impl shader::Primitive for Primitive {
         clip: &Rectangle<u32>,
     ) {
         pipeline.render(encoder, target, *clip, self.bg_color);
-        pipeline.viewcube.render(encoder, target, *clip);
+        if self.show_viewcube {
+            pipeline.viewcube.render(encoder, target, *clip);
+        }
     }
 }
 
@@ -216,6 +221,7 @@ impl Scene {
         &self,
         hover_region: Option<usize>,
         bounds: Rectangle,
+        show_viewcube: bool,
     ) -> Primitive {
         let cam = self.camera.borrow();
         self.selection.borrow_mut().vp_size = (bounds.width, bounds.height);
@@ -242,6 +248,7 @@ impl Scene {
             cam_rotation: cam.view_rotation_mat(),
             hover_region,
             bg_color,
+            show_viewcube,
         }
     }
 
@@ -256,7 +263,7 @@ impl Scene {
     ) -> Primitive {
         let cam = match self.camera_for_viewport(vp_handle) {
             Some(c) => c,
-            None => return self.build_primitive(hover_region, bounds),
+            None => return self.build_primitive(hover_region, bounds, false),
         };
 
         let mut all_wires = self.model_wires_for_viewport(vp_handle);
@@ -275,6 +282,7 @@ impl Scene {
             cam_rotation: cam.view_rotation_mat(),
             hover_region,
             bg_color: self.bg_color,
+            show_viewcube: false,
         }
     }
 
diff --git a/src/scene/viewport_pane.rs b/src/scene/viewport_pane.rs
index af50f44aa..1784ec108 100644
--- a/src/scene/viewport_pane.rs
+++ b/src/scene/viewport_pane.rs
@@ -25,18 +25,19 @@ pub enum ViewportPaneMode {
 pub struct ViewportPane<'a> {
     pub scene: &'a Scene,
     pub mode: ViewportPaneMode,
+    pub show_viewcube: bool,
 }
 
 impl<'a> ViewportPane<'a> {
-    pub fn model(scene: &'a Scene) -> Self {
-        Self { scene, mode: ViewportPaneMode::Model }
+    pub fn model(scene: &'a Scene, show_viewcube: bool) -> Self {
+        Self { scene, mode: ViewportPaneMode::Model, show_viewcube }
     }
 
     /// One paper-space viewport: model content rendered through its own camera.
     /// See [`ViewportPaneMode::Paper`] for why this is currently unused.
     #[allow(dead_code)]
     pub fn paper(scene: &'a Scene, handle: Handle) -> Self {
-        Self { scene, mode: ViewportPaneMode::Paper { handle } }
+        Self { scene, mode: ViewportPaneMode::Paper { handle }, show_viewcube: false }
     }
 }
 
@@ -106,7 +107,7 @@ impl<'a, Msg: std::fmt::Debug + Clone> shader::Program<Msg> for ViewportPane<'a>
     ) -> Self::Primitive {
         match &self.mode {
             ViewportPaneMode::Model => {
-                self.scene.build_primitive(state.hover_region, bounds)
+                self.scene.build_primitive(state.hover_region, bounds, self.show_viewcube)
             }
             ViewportPaneMode::Paper { handle } => {
                 self.scene.build_viewport_primitive(*handle, state.hover_region, bounds)
@@ -122,8 +123,10 @@ impl<'a, Msg: std::fmt::Debug + Clone> shader::Program<Msg> for ViewportPane<'a>
         cursor: mouse::Cursor,
     ) -> Option<iced::widget::Action<Msg>> {
         // ViewCube hover only makes sense in the full model-space view.
-        if matches!(self.mode, ViewportPaneMode::Model) {
+        if matches!(self.mode, ViewportPaneMode::Model) && self.show_viewcube {
             self.scene.update_viewcube_state(state, bounds, cursor);
+        } else {
+            state.hover_region = None;
         }
         let _ = event;
         None
@@ -135,7 +138,7 @@ impl<'a, Msg: std::fmt::Debug + Clone> shader::Program<Msg> for ViewportPane<'a>
         _b: Rectangle,
         _c: mouse::Cursor,
     ) -> mouse::Interaction {
-        if matches!(self.mode, ViewportPaneMode::Model) {
+        if matches!(self.mode, ViewportPaneMode::Model) && self.show_viewcube {
             self.scene.viewcube_mouse_interaction(state)
         } else {
             mouse::Interaction::default()