diff --git a/js/build_utils.js b/js/build_utils.js
index 927a265..48103ff 100644
--- a/js/build_utils.js
+++ b/js/build_utils.js
@@ -231,8 +231,15 @@ function expandItem(item) {
 }
 
 class Item {
-    constructor(item_obj) {
-        this.statMap = expandItem(item_obj);
+    constructor(item_obj = null) {
+        if (item_obj) { this.statMap = expandItem(item_obj); }
+        else { this.statMap = new Map(); }
+    }
+
+    copy() {
+        const ret = new Item();
+        ret.statMap = new Map(this.statMap);
+        return ret;
     }
 }
 
diff --git a/js/builder_graph.js b/js/builder_graph.js
index 5325574..22b0a60 100644
--- a/js/builder_graph.js
+++ b/js/builder_graph.js
@@ -203,8 +203,8 @@ class ItemPowderingNode extends ComputeNode {
 
     compute_func(input_map) {
         const powdering = input_map.get('powdering');
-        const item = {}; 
-        item.statMap = new Map(input_map.get('item').statMap);  // TODO: performance
+        const input_item = input_map.get('item');
+        const item = input_item.copy(); // TODO: performance
 
         const max_slots = item.statMap.get('slots');
         item.statMap.set('powders', powdering.slice(0, max_slots));
@@ -1021,7 +1021,7 @@ function builder_graph_init() {
     let weapon_image = document.getElementById("weapon-img");
     let weapon_dps = document.getElementById("weapon-dps");
     new WeaponInputDisplayNode('weapon-type', weapon_image, weapon_dps).link_to(item_nodes[8]);
-    
+
     // linking to atree verification
     atree_validate.link_to(level_input, 'level');
 
diff --git a/js/craft.js b/js/craft.js
index db30aef..e6a15d2 100644
--- a/js/craft.js
+++ b/js/craft.js
@@ -397,4 +397,8 @@ class Craft{
         statMap.set("crafted", true);
         this.statMap = statMap;
     }
+
+    copy() {
+        return new Craft(this.recipe, this.mat_tiers, this.ingreds, this.atkSpd, this.hash.slice(3));
+    }
 }
diff --git a/js/custom.js b/js/custom.js
index 4a6e94c..171a470 100644
--- a/js/custom.js
+++ b/js/custom.js
@@ -336,4 +336,7 @@ class Custom {
         this.statMap.set("restrict", "Custom Item")
     }
 
+    copy() {
+        return new Custom(new Map(this.statMap));
+    }
 }
diff --git a/js/load.js b/js/load.js
index 2a504cd..8b4e713 100644
--- a/js/load.js
+++ b/js/load.js
@@ -254,5 +254,4 @@ function init_maps() {
             redirectMap.set(item.id, item.remapID);
         }
     }
-    console.log(itemMap);
 }