diff --git a/src/components/ViewerControls.tsx b/src/components/ViewerControls.tsx
index 7b867e4..4cfa60c 100644
--- a/src/components/ViewerControls.tsx
+++ b/src/components/ViewerControls.tsx
@@ -41,12 +41,8 @@ export function ViewerControls() {
 
   const handleExportSelection = useCallback(async () => {
     if (!activeModel || selectedElementKeys.size === 0) return;
-    const canvas = document.querySelector('canvas') as HTMLCanvasElement | null;
-    if (!canvas) { toast.error('Canvas não encontrado'); return; }
-    // Walk the global scene to find selected element nodes
-    const scene = (canvas as unknown as { __r3f?: { fiber?: { scene?: THREE.Scene } } }).__r3f?.fiber?.scene
-      ?? (window as unknown as { __r3fScene?: THREE.Scene }).__r3fScene;
-    // Fallback: scan via DOM-attached three scene exposed by drei? Use traversal of stored models — use document approach
+    const scene = sceneRef.current;
+    if (!scene) { toast.error('Cena 3D não disponível'); return; }
     const objects: THREE.Object3D[] = [];
     const collect = (root: THREE.Object3D) => {
       const modelId = root.userData?.modelId as string | undefined;
@@ -56,7 +52,7 @@ export function ViewerControls() {
         if (selectedElementKeys.has(elementKey(modelId, el))) objects.push(el);
       });
     };
-    if (scene) collect(scene);
+    collect(scene);
     if (objects.length === 0) {
       toast.error('Não foi possível localizar elementos selecionados. Use IFC para seleção persistente.');
       return;