diff --git a/src/bin/3dView/Data/BuildNodeData.ts b/src/bin/3dView/Data/BuildNodeData.ts
index bf6fad3..4196820 100644
--- a/src/bin/3dView/Data/BuildNodeData.ts
+++ b/src/bin/3dView/Data/BuildNodeData.ts
@@ -12,6 +12,12 @@ export interface NodeData {
     topNode?: boolean
     excluded?: boolean
     inGrain?: boolean
+    /**
+     * The vertical spacing between nodes on this cable (cm).
+     * Used by GrainCableFill to offset the grain surface half a spacing above the top node,
+     * matching the 2D bin view behaviour.
+     */
+    nodeSpacing: number
 }
 
 export function BuildNodeData(cables: CableData[]): NodeData[] {
@@ -31,23 +37,13 @@ export function BuildNodeData(cables: CableData[]): NodeData[] {
 
         const spacing = height / nodeCount;
 
-        
-        grainCable.celcius.forEach((celcius,i) => {
-            
+        grainCable.celcius.forEach((celcius, i) => {
+
             const nodeY = bottomY + (i * spacing);
 
             const humidity = grainCable.relativeHumidity[i] || undefined;
             const moisture = grainCable.moisture[i] || undefined;
             let t = celcius
-            //this is for testing to force a single node to a specific temp
-            // if (i === 0) {
-            //     t = -10
-            // }            
-            // if (i === 1) {
-            //     t = 30
-            // }
-
-
 
             nodeData.push({
                 cableIndex: cableIndex,
@@ -57,13 +53,11 @@ export function BuildNodeData(cables: CableData[]): NodeData[] {
                 celcius: t,
                 humidity: humidity,
                 moisture: moisture,
-                topNode: grainCable.topNode === i+1, //top node tracking starts at 1 not 0 so add one to the index
+                topNode: grainCable.topNode === i + 1,
                 excluded: grainCable.excludedNodes?.includes(i) ?? false,
-                inGrain: i+1 <= grainCable.topNode
-                // optional: (may want to add this to the node data later)
-                // normalizedHeight: (nodeY - bottomY) / height
+                inGrain: i + 1 <= grainCable.topNode || !grainCable.topNode,
+                nodeSpacing: spacing,
             })
-
         })
     })
 
diff --git a/src/bin/3dView/Scene/Bin3dView.tsx b/src/bin/3dView/Scene/Bin3dView.tsx
index 8c0c377..45fcdb6 100644
--- a/src/bin/3dView/Scene/Bin3dView.tsx
+++ b/src/bin/3dView/Scene/Bin3dView.tsx
@@ -8,8 +8,9 @@ import { Vector3 } from "three";
 import { useMemo } from "react";
 import { BuildCableData } from "../Data/BuildCableData";
 import { BuildNodeData } from "../Data/BuildNodeData";
-import Heatmap from "../Systems/Heatmap/HeatMapAlpha";
 import NodePointCloud from "../Systems/Heatmap/NodePointCloud";
+import { pond } from "protobuf-ts/pond";
+import GrainCableFill from "../Systems/Inventory/GrainCableFill";
 
 interface Props {
     /**
@@ -37,6 +38,29 @@ export default function Bin3dView(props: Props){
     const cableData = useMemo(() => BuildCableData(bin), [bin]);
     const nodeData = useMemo(() => BuildNodeData(cableData), [cableData]);
 
+    const grainInventory = () => {
+        if(bin.inventoryControl() === pond.BinInventoryControl.BIN_INVENTORY_CONTROL_AUTOMATIC ||
+           bin.inventoryControl() === pond.BinInventoryControl.BIN_INVENTORY_CONTROL_HYBRID_CABLE){
+            return (
+                <GrainCableFill 
+                    diameter={bin.diameter()}
+                    nodes={nodeData}
+                    sidewallHeight={bin.sidewallHeight()}
+                    fallbackFillPercent={fillPercent}
+                    hopperHeight={bin.hopperHeight()}
+                    grainOpacity={0.3}
+                />
+            )
+        }else if (fillPercent){
+            <GrainFillFlat
+            diameter={bin.diameter()}
+            sidewallHeight={bin.sidewallHeight()}
+            hopperHeight={bin.hopperHeight()}
+            fillPercent={fillPercent}
+        />
+        }
+    }
+
     return (
             <Canvas>
               <group scale={[1/scale, 1/scale, 1/scale]}>
@@ -54,14 +78,7 @@ export default function Bin3dView(props: Props){
                 />
 
                 {/* grain - cylinder*/}
-                {fillPercent !== undefined && (
-                    <GrainFillFlat
-                        diameter={bin.diameter()}
-                        sidewallHeight={bin.sidewallHeight()}
-                        hopperHeight={bin.hopperHeight()}
-                        fillPercent={fillPercent}
-                    />
-                )}
+                {grainInventory()}
                 {/* cables */}
                 <BinCables cableData={cableData} nodeData={nodeData} bin={bin} binCenter={binCenter}/>
                 <NodePointCloud bin={bin} nodes={nodeData} />
diff --git a/src/bin/3dView/Systems/Inventory/GrainCableFill.tsx b/src/bin/3dView/Systems/Inventory/GrainCableFill.tsx
new file mode 100644
index 0000000..0ae8a2e
--- /dev/null
+++ b/src/bin/3dView/Systems/Inventory/GrainCableFill.tsx
@@ -0,0 +1,329 @@
+import { useMemo } from "react";
+import * as THREE from "three";
+import { NodeData } from "../../Data/BuildNodeData";
+import Cone from "3dModels/Shapes/3D/Cone";
+import { Vector3, Euler } from "three";
+import Cylinder from "3dModels/Shapes/3D/Cylinder";
+
+interface Props {
+    diameter: number;
+    sidewallHeight: number;
+    hopperHeight?: number;
+    nodes: NodeData[];
+    grainOpacity?: number
+    /**
+     * Fallback flat fill percent (0–1) used when no top nodes are available.
+     * If undefined and no top nodes exist, nothing is rendered.
+     */
+    fallbackFillPercent?: number;
+}
+
+// Tuning knobs
+const RADIAL_RINGS = 24;   // vertex rings radiating outward from center
+const THETA_SEGMENTS = 36; // vertices around each ring
+
+/**
+ * Inverse-distance weighted interpolation of Y height at a given (x, z) point.
+ * Each top node contributes a weighted Y based on its horizontal distance from the point.
+ * The power parameter controls how sharply nearer nodes dominate (2 = standard IDW).
+ */
+function idwHeight(
+    x: number,
+    z: number,
+    anchors: { x: number; z: number; y: number }[],
+    power = 2
+): number {
+    let totalWeight = 0;
+    let weightedY = 0;
+
+    for (const anchor of anchors) {
+        const dx = x - anchor.x;
+        const dz = z - anchor.z;
+        const distSq = dx * dx + dz * dz;
+
+        // If we're sitting exactly on an anchor, return its Y immediately
+        if (distSq < 0.001) return anchor.y;
+
+        const weight = 1 / Math.pow(distSq, power / 2);
+        totalWeight += weight;
+        weightedY += anchor.y * weight;
+    }
+
+    return weightedY / totalWeight;
+}
+
+export default function GrainCableFill(props: Props) {
+    const {
+        diameter,
+        sidewallHeight,
+        hopperHeight = 0,
+        nodes,
+        fallbackFillPercent,
+        grainOpacity
+    } = props;
+
+    const binRadius = diameter / 2;
+    // Slightly inset to avoid z-fighting with the shell
+    const grainRadius = binRadius * 0.98;
+    const grainColour = "#fff302";
+
+    // --- Collect top nodes (non-excluded, inGrain) ---
+    const topNodes = useMemo(() =>
+        nodes.filter(n => n.topNode && n.inGrain && !n.excluded),
+        [nodes]
+    );
+
+    // --- Build surface anchors: top node Y + half spacing offset ---
+    // This places the grain line halfway between the top node and the node above it,
+    // matching the 2D bin view convention.
+    const anchors = useMemo(() =>
+        topNodes.map(n => ({
+            x: n.position.x,
+            z: n.position.z,
+            y: n.position.y + n.nodeSpacing * 0.5,
+        })),
+        [topNodes]
+    );
+
+    // --- Wall clamp: average of all anchor Y values ---
+    // Prevents grain from piling up at the wall where there are no cables.
+    const wallY = useMemo(() => {
+        if (anchors.length === 0) return -sidewallHeight / 2;
+        return anchors.reduce((sum, a) => sum + a.y, 0) / anchors.length;
+    }, [anchors, sidewallHeight]);
+
+    // --- Build the polar surface mesh ---
+    const surfaceGeometry = useMemo(() => {
+        if (anchors.length === 0) return null;
+
+        // Total vertices: center point + (RADIAL_RINGS * THETA_SEGMENTS) ring vertices
+        const ringCount = RADIAL_RINGS;
+        const segCount = THETA_SEGMENTS;
+        const vertexCount = 1 + ringCount * segCount;
+
+        const positions = new Float32Array(vertexCount * 3);
+        const normals = new Float32Array(vertexCount * 3);
+        const uvs = new Float32Array(vertexCount * 2);
+
+        // Center vertex
+        const centerY = idwHeight(0, 0, anchors);
+        positions[0] = 0;
+        positions[1] = centerY;
+        positions[2] = 0;
+        normals[0] = 0; normals[1] = 1; normals[2] = 0;
+        uvs[0] = 0.5; uvs[1] = 0.5;
+
+        // Ring vertices
+        for (let ring = 0; ring < ringCount; ring++) {
+            // sqrt distribution for even area density across rings
+            const t = Math.sqrt((ring + 1) / ringCount);
+            const r = t * grainRadius;
+
+            for (let seg = 0; seg < segCount; seg++) {
+                const angle = (seg / segCount) * Math.PI * 2;
+                const x = Math.cos(angle) * r;
+                const z = Math.sin(angle) * r;
+
+                // Outermost ring clamps to wall average; inner rings interpolate
+                //const isOuterRing = ring === ringCount - 1;
+                // const y = idwHeight(x, z, anchors);
+                const rawY = idwHeight(x, z, anchors);
+
+                // Blend outer 20% of radius toward wallY
+                const edgeStart = 0.8; // start taper at 80% radius
+                const blendT = Math.max(0, (t - edgeStart) / (1 - edgeStart));
+                
+                // smoothstep
+                const s = blendT * blendT * (3 - 2 * blendT);
+                
+                const y = rawY * (1 - s) + wallY * s;
+
+                // Clamp Y to valid range: no higher than roof base, no lower than bin floor
+                const clampedY = Math.max(
+                    -sidewallHeight / 2,
+                    Math.min(sidewallHeight / 2, y)
+                );
+
+                const vi = (1 + ring * segCount + seg) * 3;
+                positions[vi] = x;
+                positions[vi + 1] = clampedY;
+                positions[vi + 2] = z;
+
+                // Approximate normals — pointing up (will look fine for grain)
+                normals[vi] = 0; normals[vi + 1] = 1; normals[vi + 2] = 0;
+
+                const ui = (1 + ring * segCount + seg) * 2;
+                uvs[ui] = (x / grainRadius) * 0.5 + 0.5;
+                uvs[ui + 1] = (z / grainRadius) * 0.5 + 0.5;
+            }
+        }
+
+        // --- Build triangle indices ---
+        // Center fan: triangles from center point to first ring
+        const indexList: number[] = [];
+
+        for (let seg = 0; seg < segCount; seg++) {
+            const next = (seg + 1) % segCount;
+            indexList.push(0, 1 + seg, 1 + next);
+        }
+
+        // Ring quads: two triangles per quad between adjacent rings
+        for (let ring = 0; ring < ringCount - 1; ring++) {
+            for (let seg = 0; seg < segCount; seg++) {
+                const next = (seg + 1) % segCount;
+
+                const a = 1 + ring * segCount + seg;
+                const b = 1 + ring * segCount + next;
+                const c = 1 + (ring + 1) * segCount + seg;
+                const d = 1 + (ring + 1) * segCount + next;
+
+                indexList.push(a, c, b);
+                indexList.push(b, c, d);
+            }
+        }
+
+        const geo = new THREE.BufferGeometry();
+        geo.setAttribute("position", new THREE.BufferAttribute(positions, 3));
+        geo.setAttribute("normal", new THREE.BufferAttribute(normals, 3));
+        geo.setAttribute("uv", new THREE.BufferAttribute(uvs, 2));
+        geo.setIndex(indexList);
+        geo.computeVertexNormals(); // smooth out the approximated normals
+
+        return geo;
+    }, [anchors, wallY, grainRadius, sidewallHeight]);
+
+    // --- Hopper fill (reuse existing cone approach) ---
+    // The surface mesh handles the cylindrical portion.
+    // The hopper below is always fully filled if the surface is above the bin floor.
+    const lowestSurfaceY = useMemo(() => {
+        if (anchors.length === 0) return -sidewallHeight / 2;
+        return Math.min(...anchors.map(a => a.y), wallY);
+    }, [anchors, wallY, sidewallHeight]);
+
+    const hopperIsActive = hopperHeight > 0 && lowestSurfaceY > -sidewallHeight / 2;
+
+    const hopperPosition = useMemo(
+        () => new Vector3(0, -(sidewallHeight / 2 + hopperHeight / 2), 0),
+        [sidewallHeight, hopperHeight]
+    );
+
+    const hopperRotation = useMemo(() => new Euler(Math.PI, 0, 0), []);
+
+    // --- Fallback: flat fill when no top nodes ---
+    const fallbackGeometry = useMemo(() => {
+        if (anchors.length > 0 || fallbackFillPercent === undefined) return null;
+
+        const radius = diameter / 2;
+        const fbRadius = radius * 0.98;
+        const cylinderVolume = Math.PI * radius * radius * sidewallHeight;
+        const hopperVolume = hopperHeight > 0
+            ? (1 / 3) * Math.PI * radius * radius * hopperHeight
+            : 0;
+        const totalVolume = cylinderVolume + hopperVolume;
+        const filledVolume = totalVolume * fallbackFillPercent;
+
+        let hopperFillHeight = 0;
+        let cylinderFillHeight = 0;
+
+        if (hopperHeight > 0 && filledVolume <= hopperVolume) {
+            const ratio = filledVolume / hopperVolume;
+            hopperFillHeight = hopperHeight * Math.pow(ratio, 1 / 3);
+            cylinderFillHeight = 0;
+        } else {
+            hopperFillHeight = hopperHeight;
+            const remaining = filledVolume - hopperVolume;
+            cylinderFillHeight = Math.max(0, remaining / (Math.PI * radius * radius));
+        }
+
+        return { fbRadius, hopperFillHeight, cylinderFillHeight };
+    }, [anchors.length, fallbackFillPercent, diameter, sidewallHeight, hopperHeight]);
+
+    // --- Render fallback ---
+    if (anchors.length === 0) {
+        if (!fallbackGeometry) return null;
+
+        const { fbRadius, hopperFillHeight, cylinderFillHeight } = fallbackGeometry;
+
+        return (
+            <>
+                {hopperHeight > 0 && hopperFillHeight > 0 && (
+                    <Cone
+                        geometry={{
+                            radius: fbRadius * (hopperFillHeight / hopperHeight),
+                            height: hopperFillHeight,
+                            radialSegments: 20,
+                            openEnded: false,
+                        }}
+                        position={new Vector3(0, -(sidewallHeight / 2 + hopperHeight) + hopperFillHeight / 2, 0)}
+                        rotation={new Euler(Math.PI, 0, 0)}
+                        colour={grainColour}
+                        roughness={1}
+                        metalness={0}
+                        opacity={grainOpacity}
+                    />
+                )}
+                {cylinderFillHeight > 0 && (
+                    <mesh position={new Vector3(0, -sidewallHeight / 2 + cylinderFillHeight / 2, 0)}>
+                        <cylinderGeometry args={[fbRadius, fbRadius, cylinderFillHeight, 20, 1, false]} />
+                        <meshStandardMaterial color={grainColour} roughness={1} metalness={0} opacity={grainOpacity}/>
+                    </mesh>
+                )}
+            </>
+        );
+    }
+
+    // --- Render cable-driven surface ---
+    return (
+        <>
+            {/* Interpolated grain surface */}
+            {surfaceGeometry && (
+                <mesh geometry={surfaceGeometry}>
+                    <meshStandardMaterial
+                        color={grainColour}
+                        roughness={1}
+                        metalness={0}
+                        side={THREE.DoubleSide}
+                        transparent
+                        opacity={grainOpacity}
+                        depthWrite={false}
+                    />
+                </mesh>
+            )}
+
+            {/* Cylindrical body of grain below the surface down to the bin floor / hopper top */}
+            <Cylinder 
+                position={new Vector3(0, -sidewallHeight / 2 + wallY / 2 + sidewallHeight / 4, 0)}
+                geometry={{
+                    height: sidewallHeight / 2 + wallY,
+                    radiusBottom: grainRadius,
+                    radiusTop: grainRadius,
+                    radialSegments: THETA_SEGMENTS,
+                    heightSegments: 1,
+                    openEnded: false
+                }}
+                colour={grainColour}
+                roughness={1}
+                opacity={grainOpacity}
+                depthWrite={false}
+            />
+
+            {/* Hopper fill — always full when grain surface exists above the floor */}
+            {hopperIsActive && (
+                <Cone
+                    geometry={{
+                        radius: grainRadius,
+                        height: hopperHeight,
+                        radialSegments: THETA_SEGMENTS,
+                        openEnded: false,
+                    }}
+                    position={hopperPosition}
+                    rotation={hopperRotation}
+                    colour={grainColour}
+                    roughness={1}
+                    metalness={0}
+                    opacity={grainOpacity}
+                />
+            )}
+        </>
+    );
+}
\ No newline at end of file