diff --git a/sources/scripts/dotgrid.js b/sources/scripts/dotgrid.js
index a27674b..9e63829 100644
--- a/sources/scripts/dotgrid.js
+++ b/sources/scripts/dotgrid.js
@@ -212,7 +212,7 @@ function Dotgrid(width,height,grid_x,grid_y,block_x,block_y,thickness = 3,lineca
 
     fs.readFile(paths[0], 'utf-8', (err, data) => {
       if(err){ alert("An error ocurred reading the file :" + err.message); return; }
-      dotgrid.tool.import(JSON.parse(data.toString().trim()));
+      dotgrid.tool.replace(JSON.parse(data.toString().trim()));
       dotgrid.draw();
     });
   }
@@ -468,7 +468,7 @@ function Dotgrid(width,height,grid_x,grid_y,block_x,block_y,thickness = 3,lineca
 
     var reader = new FileReader();
     reader.onload = function(e){
-      dotgrid.tool.import(JSON.parse(e.target.result.toString().trim()));
+      dotgrid.tool.replace(JSON.parse(e.target.result.toString().trim()));
       dotgrid.draw();
     };
     reader.readAsText(file);
diff --git a/sources/scripts/tool.js b/sources/scripts/tool.js
index e3ca831..909b91a 100644
--- a/sources/scripts/tool.js
+++ b/sources/scripts/tool.js
@@ -175,6 +175,16 @@ function Tool()
     return JSON.stringify(copy(target), null, 2);
   }
 
+  this.replace = function(layers)
+  {
+    if(layers.length != 3){ console.log("Incompatible"); return; }
+    
+    this.layers = layers;
+    this.clear();
+    dotgrid.draw();
+    dotgrid.history.push(this.layers);
+  }
+
   this.import = function(layer)
   {
     this.layers[this.index] = this.layers[this.index].concat(layer)