diff --git a/resources/views/rd/fire-shutter-drawing/index.blade.php b/resources/views/rd/fire-shutter-drawing/index.blade.php
index 5b2bf7dd..59c01cf1 100644
--- a/resources/views/rd/fire-shutter-drawing/index.blade.php
+++ b/resources/views/rd/fire-shutter-drawing/index.blade.php
@@ -1241,7 +1241,7 @@ function fs3dBuild() {
         const motorR = b.shaftDia * 0.45;
         const shaftSprocketR = 70; // 브라켓 높이(180mm) 내 크기 (ø140)
         const motorSprocketR = 30; // 모터측 작은 스프로켓 (ø60)
-        const motorZ = -(shaftSprocketR + motorSprocketR + 170); // 모터 Z 오프셋 (슬랫 감김 간섭 방지 +150mm)
+        const motorZ = -(shaftSprocketR + motorSprocketR + 95); // 모터 Z 오프셋 (슬랫 감김 간섭 방지 +75mm)
         // 브라켓: Z 중심은 샤프트(0)와 모터(motorZ) 사이
         const motorBkGeo = new THREE.BoxGeometry(motorBkThick, motorBkH, motorBkW);
         const motorBk = new THREE.Mesh(motorBkGeo, bracketMat);
@@ -1348,23 +1348,6 @@ function fs3dBuild() {
         chainLine.position.x = shaftSprocketX;
         meshes.motor.add(chainLine);
 
-        // 체인 직선 두께 (상/하단 — 스프로켓 반지름 차이만큼 기울기 적용)
-        const tangentLen = Math.sqrt(Math.pow(R1 - R2, 2) + motorZ * motorZ);
-        if (tangentLen > 10) {
-            const halfZ = motorZ / 2;
-            const chainTilt = Math.atan2(R1 - R2, Math.abs(motorZ)); // 반지름 차이에 의한 기울기
-            // 상단 직선
-            const csGeo = new THREE.BoxGeometry(6, 4, tangentLen);
-            const csTop = new THREE.Mesh(csGeo, chainMat);
-            csTop.position.set(shaftSprocketX, (R1 + R2) / 2, halfZ);
-            csTop.rotation.x = chainTilt;
-            meshes.motor.add(csTop);
-            // 하단 직선
-            const csBot = new THREE.Mesh(csGeo.clone(), chainMat);
-            csBot.position.set(shaftSprocketX, -(R1 + R2) / 2, halfZ);
-            csBot.rotation.x = -chainTilt;
-            meshes.motor.add(csBot);
-        }
 
         meshes.motor.position.set(0, shaftY, 0);
         scene.add(meshes.motor);