diff --git a/src/kiri/conf.js b/src/kiri/conf.js
index f829a6ec..d30ad979 100644
--- a/src/kiri/conf.js
+++ b/src/kiri/conf.js
@@ -479,6 +479,7 @@
                     processName: "default",
                     laserOffset: 0.25,
                     laserSliceHeight: 1,
+                    laserSliceHeightMin: 0,
                     laserSliceSingle: false,
                     outputTileSpacing: 1,
                     outputTileScaling: 1,
diff --git a/src/kiri/init.js b/src/kiri/init.js
index a6d73824..4556d872 100644
--- a/src/kiri/init.js
+++ b/src/kiri/init.js
@@ -1352,7 +1352,8 @@
             sliceBottomLayers:   UC.newInput(LANG.sl_lbot_s, {title:LANG.sl_lbot_l, convert:UC.toInt, modes:FDM}),
 
             laserOffset:         UC.newInput(LANG.ls_offs_s, {title:LANG.ls_offs_l, convert:UC.toFloat, modes:LASER}),
-            laserSliceHeight:    UC.newInput(LANG.ls_lahi_s, {title:LANG.ls_lahi_l, convert:UC.toFloat, modes:LASER}),
+            laserSliceHeight:    UC.newInput(LANG.ls_lahi_s, {title:LANG.ls_lahi_l, convert:UC.toFloat, modes:LASER, trigger: true}),
+            laserSliceHeightMin: UC.newInput(LANG.ls_lahm_s, {title:LANG.ls_lahm_l, convert:UC.toFloat, modes:LASER, show:() => { return UI.laserSliceHeight.value == 0 }}),
             laserSliceSingle:    UC.newBoolean(LANG.ls_sngl_s, onBooleanClick, {title:LANG.ls_sngl_l, modes:LASER}),
 
             fdmInfill:           UC.newGroup(LANG.fi_menu, $('settings'), {modes:FDM, marker:true}),
diff --git a/src/kiri/slicer.js b/src/kiri/slicer.js
index 9f528d22..de012f8c 100644
--- a/src/kiri/slicer.js
+++ b/src/kiri/slicer.js
@@ -241,6 +241,18 @@
             // use Z indices in auto slice mode for laser
             // find unique z-index offsets for slicing
             let zl = zOrdered
+            // if zIncMin also present, then merge adjacent
+            // slices less than that value
+            if (zIncMin) {
+                let last = undefined;
+                zl = zl.filter(v => {
+                    if (last !== undefined && v - last < zIncMin) {
+                        return false;
+                    }
+                    last = v;
+                    return true;
+                });
+            }
             for (i = 0; i < zl.length - 1; i++) {
                 zIndexes.push((zl[i] + zl[i+1]) / 2);
             }
diff --git a/src/kiri/ui.js b/src/kiri/ui.js
index 90b14aa8..27e18e41 100644
--- a/src/kiri/ui.js
+++ b/src/kiri/ui.js
@@ -122,7 +122,7 @@
         });
     }
 
-    function setMode(mode) {
+    function setMode(mode, nohide) {
         Object.keys(groupShow).forEach(group => {
             updateGroupShow(group);
         });
@@ -130,7 +130,9 @@
         hasModes.forEach(function(div) {
             div.setMode(div._group && !groupShow[div._group] ? NOMODE : mode);
         });
-        hidePoppers();
+        if (!nohide) {
+            hidePoppers();
+        }
     }
 
     function setExpert(bool) {
@@ -326,8 +328,9 @@
         };
         el.setMode = function(mode) {
             let show = opt.expert === undefined || (opt.expert === letExpert);
+            let test = !opt.show || (opt.show && opt.show());
             let disp = opt.visible ? opt.visible() : true;
-            el.setVisible(el.hasMode(mode) && show && disp);
+            el.setVisible(el.hasMode(mode) && test && show && disp);
         }
         el.hasMode = function(mode) {
             if (mode === NOMODE) return false;
@@ -569,6 +572,9 @@
             });
             ip.addEventListener('blur', function(event) {
                 action(event);
+                if (opt.trigger) {
+                    setMode(letMode, true);
+                }
             });
         }
         if (!ip.convert) ip.convert = raw.bind(ip);
diff --git a/src/mode/laser/driver.js b/src/mode/laser/driver.js
index 948d8a5b..39eda463 100644
--- a/src/mode/laser/driver.js
+++ b/src/mode/laser/driver.js
@@ -40,7 +40,9 @@
         }
 
         SLICER.sliceWidget(widget, {
-            height: proc.laserSliceHeight, single: proc.laserSliceSingle
+            single: proc.laserSliceSingle,
+            height: proc.laserSliceHeight,
+            minHeight: proc.laserSliceHeight === 0 ? proc.laserSliceHeightMin : 0
         }, function(slices) {
             widget.slices = slices;
             slices.forEach(function(slice, index) {
diff --git a/web/kiri/lang/en.js b/web/kiri/lang/en.js
index 27d72651..5b8e54f5 100644
--- a/web/kiri/lang/en.js
+++ b/web/kiri/lang/en.js
@@ -224,6 +224,8 @@ kiri.lang['en-us'] = {
     ls_offs_l:      "adjust for beam width\nin millimeters",
     ls_lahi_s:      "height",
     ls_lahi_l:      "layer height\nin millimeters\n0 = auto/detect",
+    ls_lahm_s:      "min",
+    ls_lahm_l:      "layer height minimum\nwill merge auto slices\nunder this thickness\nin millimeters",
     ls_sngl_s:      "single",
     ls_sngl_l:      "perform only one slice\nat specified layer height",