diff --git a/hardware/Makefile b/hardware/Makefile
index ac9f5ed..0e515bb 100644
--- a/hardware/Makefile
+++ b/hardware/Makefile
@@ -25,7 +25,8 @@
 PREFIX=intval3
 
 OPENSCAD=openscad
-OPENSCAD_OPTIONS=-D VERBOSE=false
+OPENSCAD_OPTIONS_STL=--enable sort-stl -D VERBOSE=false
+OPENSCAD_OPTIONS_DXF=-D VERBOSE=false
 
 STL=./stl
 DXF=./dxf
@@ -48,7 +49,7 @@ cleanall:
 # Dependencies for models
 
 $(MODELS) : $(STL)/$(PREFIX)_%.stl : $(PREFIX).scad
-	$(OPENSCAD) $(OPENSCAD_OPTIONS) -o $@ -D MODEL=\"$(subst $(PREFIX)_,,$(subst .stl,,$(@F)))\" $<
+	$(OPENSCAD) $(OPENSCAD_OPTIONS_STL) -o $@ -D MODEL=\"$(subst $(PREFIX)_,,$(subst .stl,,$(@F)))\" $<
 
 $(LASER) : $(DXF)/$(PREFIX)_%.dxf : $(PREFIX).scad
-	$(OPENSCAD) $(OPENSCAD_OPTIONS) -o $@ -D LASER=\"$(subst $(PREFIX)_,,$(subst .dxf,,$(@F)))\" $<
\ No newline at end of file
+	$(OPENSCAD) $(OPENSCAD_OPTIONS_DXF) -o $@ -D LASER=\"$(subst $(PREFIX)_,,$(subst .dxf,,$(@F)))\" $<
\ No newline at end of file