diff --git a/src/components/ViewerControls.tsx b/src/components/ViewerControls.tsx
index eb0138d..6bd27f6 100644
--- a/src/components/ViewerControls.tsx
+++ b/src/components/ViewerControls.tsx
@@ -146,6 +146,23 @@ export function ViewerControls() {
           </PopoverContent>
         </Popover>
       )}
+      {/* Posicionar (manual mouse placement) */}
+      <Button
+        variant={positionMode ? 'default' : 'outline'}
+        size="sm"
+        className="gap-2 h-9"
+        onClick={() => setPositionMode(!positionMode)}
+        disabled={!activeModelId}
+        title="Arraste: mover · Shift+arraste ou meio: profundidade · Direito: girar · Shift+direito: rotZ"
+      >
+        <Move3D className="h-3.5 w-3.5" />
+        <span className="font-mono text-xs">
+          {positionMode
+            ? `Posicionando${activeModel ? ` · ${activeModel.fileName.slice(0, 14)}` : ''}`
+            : 'Posicionar'}
+        </span>
+      </Button>
+
       {/* Measure tool */}
       <div className="flex items-end gap-1.5">
         <Button