diff --git a/src/stores/useModelStore.ts b/src/stores/useModelStore.ts
index 3f1e0ef..87f7584 100644
--- a/src/stores/useModelStore.ts
+++ b/src/stores/useModelStore.ts
@@ -163,6 +163,9 @@ export const useModelStore = create<ModelStore>((set) => ({
   xrSupported: null,
   setXrSupported: (xrSupported) => set({ xrSupported }),
 
+  scaleRatio: SCALE_PRESETS.find(p => p.label === '1:1')!,
+  setScaleRatio: (scaleRatio) => set({ scaleRatio }),
+
   opacity: 1,
   setOpacity: (opacity) => set({ opacity }),