diff --git a/cameo/templates/mkmk-simple b/cameo/templates/mkmk-simple
index 1d8a2c8..2b2a912 100755
--- a/cameo/templates/mkmk-simple
+++ b/cameo/templates/mkmk-simple
@@ -13,6 +13,7 @@ PATH=$PATH:/home/moko/svn.openmoko.org/developers/werner/cncmap/gp2rml
 # DRILL		drill diameter range, default: 13mil,14mil
 # MILL_IN	diameter of mill for work inside the board, default: 35mil
 # MILL_OUT	diameter of mill for board edge, default: 35mil
+# BOARD_Z	board tickness, default: 0.8 mm
 #
 
 while [ "$1" ]; do
@@ -30,6 +31,7 @@ fi
 : ${DRILL:="13mil 14mil"}
 : ${MILL_IN:=35mil}
 : ${MILL_OUT:=35mil}
+: ${BOARD_Z:=0.8mm}
 
 rot=
 if [ "$ROT" ]; then
@@ -52,7 +54,7 @@ translate 4mm 4mm	# move to PCB zone assigned to project
 array +3mm +3mm `expr $X + $xi` `expr $Y + $yi`
 z 0 -58.9mm		# board surface (tool fully retracted)
 z 1.5mm			# slack for extending the tool
-z -0.8mm		# board thickness
+z -$BOARD_Z		# board thickness
 z -0.5mm		# tool extra depth
 clear