diff --git a/resources/views/rd/fire-shutter-drawing/index.blade.php b/resources/views/rd/fire-shutter-drawing/index.blade.php
index 36a68bee..2a0296b6 100644
--- a/resources/views/rd/fire-shutter-drawing/index.blade.php
+++ b/resources/views/rd/fire-shutter-drawing/index.blade.php
@@ -257,7 +257,7 @@
                         <!-- 개폐율: 한 행 -->
                         <div class="flex items-center gap-2 mb-1">
                             <label class="text-[10px] text-slate-500 font-bold shrink-0" style="width:24px;">개폐</label>
-                            <input type="range" id="shutterPos" min="0" max="100" value="50" class="flex-1 accent-blue-500" style="height:3px;" oninput="fs3dShutterPos(this.value)">
+                            <input type="range" id="shutterPos" min="0" max="100" value="100" class="flex-1 accent-blue-500" style="height:3px;" oninput="fs3dShutterPos(this.value)">
                             <span id="shutterPosLabel" class="text-[10px] text-blue-400 font-black shrink-0" style="width:28px;text-align:right;">100%</span>
                         </div>
                         <!-- 투명도: 한 행 -->
@@ -406,7 +406,7 @@
         // Shutter Box
         sb: { width:2280, height:380, depth:500, thickness:1.6, shaftDia:80, bracketW:10, motorSide:'right', viewMode:'side', showShaft:true, showSlatRoll:true, showMotor:true, showBrake:true, showSpring:true },
         // 3D
-        td: { shutterPos:50, caseOpacity:0.3, lightPreset:'default', bgColor:'#ffffff', show:{ case:true, shaft:true, motor:true, rails:true, slats:true, bottomBar:true, wall:false, slatRoll:true } },
+        td: { shutterPos:100, caseOpacity:0.3, lightPreset:'default', bgColor:'#ffffff', show:{ case:true, shaft:true, motor:true, rails:true, slats:true, bottomBar:true, wall:false, slatRoll:true } },
         // Wall (벽체)
         wall: { wing:600, thick:600, topMargin:300, color:'#a1887f', opacity:30 },
         // View
@@ -2436,12 +2436,14 @@ function createRailGroup() {
             meshes.slats.add(lineGroup);
         }
 
-        // === SLAT ROLL (샤프트에 감긴 슬랫 — 샤프트 전체에 두껍게 감기는 실린더) ===
+        // === SLAT ROLL (샤프트에 감긴 슬랫 — 항상 최소 반 바퀴 감김 표시) ===
         const rolledH = H - shutterH;
-        if (rolledH > 0) {
+        {   // 스크린 100% 내려도 샤프트에 최소 감김량 표시 (물리적 연결)
+            const minRollH = H * 0.08;
+            const effectiveRolledH = Math.max(rolledH, minRollH);
             const wrapThick = S.productType === 'steel' ? 10 : 1;
             const shaftR = b.shaftDia / 2;
-            const rollThick = Math.max(Math.sqrt(rolledH * wrapThick / Math.PI), 8);
+            const rollThick = Math.max(Math.sqrt(effectiveRolledH * wrapThick / Math.PI), 8);
             const rollOuterR = shaftR + rollThick;
             const rollLen = W - 30 - stubPinVisible * 2; // 샤프트 관 길이에 맞춤