diff --git a/release.md b/release.md
index 1da419f1..9dce24f1 100644
--- a/release.md
+++ b/release.md
@@ -14,6 +14,7 @@ Full docs @ https://docs.grid.space/projects/kiri-moto
 
 ## Mesh:Tool
 
+* `C` multi-body identification and isolation
 * `-` parameterize svg and image import
 
 
diff --git a/src/mesh/api.js b/src/mesh/api.js
index 9073c6ac..6cc3a27e 100644
--- a/src/mesh/api.js
+++ b/src/mesh/api.js
@@ -400,6 +400,26 @@ const tool = {
         });
     },
 
+    isolate(models) {
+        models = fallback(models);
+        api.log.emit('isolating bodies').pin();
+        let promises = [];
+        let mcore = new Matrix4().makeRotationX(Math.PI / 2);
+        for (let m of models) {
+            let p = worker.model_isolate({ id: m.id }).then(bodies => {
+                bodies = bodies.map(vert => new mesh.model({
+                    file: m.file,
+                    mesh: vert.toFloat32()
+                })).map( nm => nm.applyMatrix4(mcore.clone().multiply(m.mesh.matrixWorld)) );
+                mesh.api.group.new(bodies, undefined, "isolate").setSelected();
+            });
+            promises.push(p);
+        }
+        Promise.all(promises).then(() => {
+            api.log.emit('isolation complete').unpin();
+        });
+    },
+
     mapFaces(models) {
         models = fallback(models);
         api.log.emit('mapping faces').pin();
diff --git a/src/mesh/build.js b/src/mesh/build.js
index b20b9564..c05a0f6c 100644
--- a/src/mesh/build.js
+++ b/src/mesh/build.js
@@ -377,6 +377,7 @@ function ui_build() {
             h.div({ _: "repair", class: "head" }),
             // h.div({ class: "vsep" }),
             h.button({ _: 'analyze', onclick: tool.analyze }),
+            h.button({ _: 'isolate', onclick: tool.isolate }),
             h.button({ _: 'patch', onclick: tool.repair }),
             // h.button({ _: 'rebuild', onclick: tool.rebuild }),
             h.button({ _: 'clean', onclick: tool.clean }),
diff --git a/src/mesh/tool.js b/src/mesh/tool.js
index 8324616d..5fe8a615 100644
--- a/src/mesh/tool.js
+++ b/src/mesh/tool.js
@@ -101,7 +101,7 @@ mesh.tool = class MeshTool {
     }
 
     generateFaceMap(vertices) {
-        this.checkVertices(vertices, 3);
+        this.vertices = this.checkVertices(vertices, 3);
         const normals = this.normals = [];
         const sides = this.sides = [];
         const _va = new THREE.Vector3();
@@ -158,12 +158,13 @@ mesh.tool = class MeshTool {
         return sides.map(side => this.side2face[side].filter(v => v != face)).flat();
     }
 
-    findConnectedSurface(faces, radians, filterZ) {
-        const found = {};
+    // depends on generateFaceMap() being run first
+    findConnectedSurface(faces, radians, filterZ, found = {}) {
         const norms = this.normals;
         if (filterZ) {
             faces = faces.filter(f => norms[f][2] >= filterZ);
         }
+        const checked = {};
         const check = faces.slice();
         for (let face of faces) {
             found[face] = 1;
@@ -173,11 +174,17 @@ mesh.tool = class MeshTool {
         while (check.length) {
             const face = check.shift();
             const norm = norms[face];
+            // if (!norm || norm.length < 3) {
+            //     throw `invalid face ${face}`;
+            // }
             if (filterZ !== undefined && norm[2] < filterZ) {
                 continue;
             }
-            const fadj = this.getAdjacentFaces(face).filter(f => !found[f]);
+            const fadj = this.getAdjacentFaces(face);
             for (let f of fadj) {
+                if (found[f] || checked[f]) {
+                    continue;
+                }
                 // #1 most accurate
                 // const nf = this.normals[f];
                 // _v1.set(nf[0], nf[1], nf[2]);
@@ -195,6 +202,7 @@ mesh.tool = class MeshTool {
                 if (fn <= radians) {
                     faces.push(f);
                     check.push(f)
+                    checked[f] = 1;
                     found[f] = 1;
                 }
             }
@@ -202,6 +210,29 @@ mesh.tool = class MeshTool {
         return faces;
     }
 
+    // depends on generateFaceMap() being run first
+    isolateBodies() {
+        const verts = this.checkVertices(this.vertices);
+        const bodies = [];
+        const used = {};
+        for (let i=0, l=this.normals.length-1; i<l; i++) {
+            if (used[i]) {
+                continue;
+            }
+            const body = this.findConnectedSurface([i], Infinity, undefined, used);
+            if (body.length) {
+                // todo: pre-allocate known length
+                // then copy array regions from verts to bverts
+                const bverts = [];
+                for (let f of body) {
+                    bverts.push(...verts.slice(f*9, f*9+9));
+                }
+                bodies.push(bverts);
+            }
+        }
+        return bodies;
+    }
+
     /**
      * finds edge lines which are line segments on a single face.
      * construct ordered line maps with array of connected edges.
diff --git a/src/mesh/work.js b/src/mesh/work.js
index f6dcb3fd..78733972 100644
--- a/src/mesh/work.js
+++ b/src/mesh/work.js
@@ -76,16 +76,21 @@ function analyze(id, opt = {}) {
     return tool;
 }
 
-function mapFaces(id, opt = {}) {
+function isolateBodies(id) {
+    let tool = mapFaces(id);
+    log(`${id} | isolating bodies`);
+    return tool.isolateBodies();
+}
+
+function mapFaces(id) {
     let rec = cache[id];
     let { geo, tool } = rec;
     if (!tool) {
         tool = rec.tool = new mesh.tool();
     }
-    const vertices = geo.attributes.position.array;
     if (!tool.normals) {
         log(`${id} | generating face map`);
-        tool.generateFaceMap(vertices);
+        tool.generateFaceMap(geo.attributes.position.array);
     }
     return tool;
 }
@@ -275,11 +280,16 @@ let model = {
     },
 
     mapFaces(data) {
-        let { id, opt } = data;
-        let tool = mapFaces(id, opt);
+        let { id } = data;
+        let tool = mapFaces(id);
         return { mapped: true };
     },
 
+    isolate(data) {
+        let { id } = data;
+        return isolateBodies(id);
+    },
+
     // given model and point, locate matching vertices, lines, and faces
     select(data) {
         let { id, x, y, z, a, b, c, matrix, surface } = data;