diff --git a/src/kiri/print.js b/src/kiri/print.js
index b45fab6a..e1b35ef7 100644
--- a/src/kiri/print.js
+++ b/src/kiri/print.js
@@ -808,7 +808,9 @@
      */
     function addPrintPoints(input, output, startPoint, tool) {
         if (startPoint && input.length > 0) {
-            addOutput(output, startPoint, 0, undefined, tool);
+            lastPoint = startPoint;
+            // TODO: revisit seek to origin as the first move
+            // addOutput(output, startPoint, 0, undefined, tool);
         }
         output.appendAll(input);
     }
diff --git a/src/kiri/worker.js b/src/kiri/worker.js
index 8ebf74e4..0d399c46 100644
--- a/src/kiri/worker.js
+++ b/src/kiri/worker.js
@@ -74,11 +74,21 @@ KIRI.worker = {
 
         let rotation = (Math.PI/180) * (settings.device.bedBelt ? 45 : 0);
         if (rotation) {
-            let bounds = widget.getBoundingBox(true);
+            // need min y for post-rotation offset in prepare
+            let vert = widget.vertices;
+            let miny = Infinity;
+            for (let i=0, l=vert.length; i<l; ) {
+                let x = vert[i++];
+                let y = vert[i++];
+                let z = vert[i++];
+                if (z < 0.01) miny = Math.min(miny, y);
+            }
+
+            widget.getBoundingBox(true);
             let track = widget.track;
-            // console.log(widget.id, '\n', track.pos, '\n', track.box, '\n', '\n---\n')
             xpos = track.pos.x;
-            ypos = track.pos.y + settings.device.bedDepth / 2 - track.box.h / 2;
+            ypos = settings.device.bedDepth / 2 + track.pos.y + miny;
+
             widget.mesh = null;
             widget.points = null;
             widget.loadVertices(widget.vertices);
@@ -112,7 +122,6 @@ KIRI.worker = {
                     let dy = (wbb.max.y + wbb.min.y)/2;
                     let dz = wbb.min.z;
                     widget.rotinfo = { angle: 45, dy, dz, xpos, ypos };
-                    // console.log(widget.id, '\n', widget.belt, '\n', widget.rotinfo, '\n===\n')
                     send.data({ rotinfo: widget.rotinfo });
                 }
             }
diff --git a/src/mode/fdm/export.js b/src/mode/fdm/export.js
index 41c85a26..a6f6f235 100644
--- a/src/mode/fdm/export.js
+++ b/src/mode/fdm/export.js
@@ -182,20 +182,20 @@
                 append(";; " + comment);
             }
             let o = [!rate && !newpos.e ? 'G0' : 'G1'];
-            // put out x,y,z in belt mode if not engage/retract
-            let xyz = newpos.x || newpos.y || newpos.z;
-            let emit = { x: xyz && isBelt, y: xyz && isBelt, z: xyz && isBelt };
-            if (typeof newpos.x === 'number') {
+            let emit = { x: false, y: false, z: false };
+            if (typeof newpos.x === 'number' && newpos.x !== pos.x) {
                 pos.x = newpos.x;
                 emit.x = true;
             }
-            if (typeof newpos.y === 'number') {
+            if (typeof newpos.y === 'number' && newpos.y !== pos.y) {
                 pos.y = newpos.y;
                 emit.y = true;
+                if (isBelt) emit.z = true;
             }
-            if (typeof newpos.z === 'number') {
+            if (typeof newpos.z === 'number' && newpos.z !== pos.z) {
                 pos.z = newpos.z;
                 emit.z = true;
+                if (isBelt) emit.y = true;
             }
             let epos = isBelt ? { x: pos.x, y: pos.y, z: pos.z } : pos;
             if (isBelt) {
@@ -249,11 +249,14 @@
                     (process.firstSliceHeight || process.sliceHeight) : path.height);
 
             subst.z = zpos = path.z;
-            // subst.z = (zpos + path.height).toFixed(3);
             subst.Z = subst.z;
             subst.layer = layer;
             subst.height = path.height.toFixed(3);
 
+            if (isBelt) {
+                pos.z = zpos;
+            }
+
             if (pauseCmd && pause.indexOf(layer) >= 0) {
                 appendAllSub(pauseCmd)
             }
diff --git a/src/mode/fdm/prepare.js b/src/mode/fdm/prepare.js
index 6aebf308..75d45e10 100644
--- a/src/mode/fdm/prepare.js
+++ b/src/mode/fdm/prepare.js
@@ -292,9 +292,9 @@
             let offset = widget.mesh ? Object.clone(widget.mesh.position) : {x:0, y:0, z:0};
             if (isBelt) {
                 offset.x = widget.rotinfo.xpos;
-                offset.y = widget.belt.miny;
+                offset.y = -widget.belt.midy;
                 offset.y += widget.rotinfo.ypos * beltfact;
-                offset.z = widget.rotinfo.ypos * beltfact;
+                offset.z  = widget.rotinfo.ypos * beltfact;
             } else {
                 // when rafts used this is non-zero
                 offset.z = zoff;
@@ -385,23 +385,28 @@
                 // alter settings for base extrusions (touching the bed)
                 if (isBelt) {
                     let widget = slice.widget;
-                    let lastout, minx = Infinity, maxx = -Infinity, first = false;
+                    let lastout, first = false;
+                    let minz = Infinity, maxy = -Infinity, minx = Infinity, maxx = -Infinity;
+                    let thresh = firstLayerHeight * 1.1;
                     for (let out of tmpout) {
                         let point = out.point;
                         let belty = out.belty = -point.y + point.z * bfactor;
-                        if (out.emit && belty < firstLayerHeight && lastout && lastout.belty < firstLayerHeight) {
+                        if (out.emit && belty < thresh && lastout && lastout.belty < thresh) {
                             out.speed = firstLayerRate;
                             out.emit *= firstLayerMult;
                             minx = Math.min(minx, point.x, lastout.point.x);
                             maxx = Math.max(maxx, point.x, lastout.point.x);
+                            maxy = Math.max(maxy, point.y);
+                            minz = Math.min(minz, point.z);
                             first = out;
                         }
                         lastout = out;
                     }
                     // add brim, if specified
                     if (first && firstLayerBrim) {
-                        let {emit, tool, point} = first;
-                        let {x, y, z} = point;
+                        let {emit, tool } = first;
+                        let y = maxy;
+                        let z = minz;
                         let b = Math.max(firstLayerBrim, 1);
                         print.addOutput(tmpout, newPoint(minx - b, y, z), 0,    firstLayerSeek, tool);
                         print.addOutput(tmpout, newPoint(minx - 0, y, z), emit, firstLayerRate, tool);
diff --git a/src/mode/fdm/slice.js b/src/mode/fdm/slice.js
index 65b776a8..994583fa 100644
--- a/src/mode/fdm/slice.js
+++ b/src/mode/fdm/slice.js
@@ -275,6 +275,7 @@
                     bounds.merge(top.poly.bounds);
                 }
                 widget.belt.miny = -bounds.miny;
+                widget.belt.midy = (bounds.miny + bounds.maxy) / 2;
             }
 
             // report slicing complete