diff --git a/src/model/model.cpp b/src/model/model.cpp
index b61ab60..b37e8f7 100644
--- a/src/model/model.cpp
+++ b/src/model/model.cpp
@@ -699,7 +699,7 @@ bool block::canPrint() const
     return false;
 }
 
-block::block_info block::save(yaml &root) const
+block::block_info block::save(yaml root) const
 {
     aim_vector4 min{ 1e6, 1e6, 1e6, 1e6 }, max{ -1e6, -1e6, -1e6, -1e6 };
     for (auto &v : md.vertices)
@@ -796,7 +796,7 @@ void model::print(const std::string &fn, AxisSystem as) const
     print_obj(fn + ".obj");
 }
 
-void model::save(yaml &root) const
+void model::save(yaml root) const
 {
     aim_vector4 min{ 1e6, 1e6, 1e6, 1e6 }, max{ -1e6, -1e6, -1e6, -1e6 };
 
diff --git a/src/model/model.h b/src/model/model.h
index 0989c20..4cccfc1 100644
--- a/src/model/model.h
+++ b/src/model/model.h
@@ -347,7 +347,7 @@ struct block
 
     std::string printMtl() const;
     std::string printObj(int v_offset, int n_offset, int uv_offset, AxisSystem as) const;
-    block_info save(yaml &root) const;
+    block_info save(yaml root) const;
 
     bool canPrint() const;
     bool isEngineFx() const;
@@ -365,7 +365,7 @@ struct model
 
     void print(const std::string &fn, AxisSystem) const;
     void printFbx(const std::string &fn, AxisSystem) const;
-    void save(yaml &root) const;
+    void save(yaml root) const;
 };
 
 float scale_mult();