diff --git a/lib/nom/nom.rb b/lib/nom/nom.rb
index c9fb721..2c11951 100644
--- a/lib/nom/nom.rb
+++ b/lib/nom/nom.rb
@@ -190,9 +190,8 @@ def plot
             end
             input_dat.close
 
-            svg = Tempfile.new(["plot", ".svg"])
+            svg = Tempfile.create(["plot", ".svg"])
             svg.close
-            ObjectSpace.undefine_finalizer(svg) # prevent the svg file from being deleted
 
             plt_erb = IO.read(File.join(File.dirname(File.expand_path(__FILE__)), "nom.plt.erb"))