diff --git a/src/components/three/viewCubeBus.ts b/src/components/three/viewCubeBus.ts
index cf9e3b8..85bbadc 100644
--- a/src/components/three/viewCubeBus.ts
+++ b/src/components/three/viewCubeBus.ts
@@ -164,7 +164,11 @@ export function pushModelFaceNormal(normalWorld: THREE.Vector3, calGroupWorldQua
   const cubeWorld = calibration.pendingCube;
   const inv = calGroupWorldQuat.clone().invert();
   const cubeLocal = cubeWorld.clone().applyQuaternion(inv).normalize();
-  const modelLocal = normalWorld.clone().applyQuaternion(inv).normalize();
+  const modelLocalRaw = normalWorld.clone().applyQuaternion(inv).normalize();
+  // Snap near-axial picks (chamfered or slightly off faces) to the closest
+  // principal axis. This dramatically improves robustness when picking faces
+  // from an orthographic head-on view.
+  const modelLocal = snapToPrincipalAxis(modelLocalRaw, 12);
   calibration.pairs.push({ cube: cubeLocal, model: modelLocal });
   calibration.pendingCube = null;