diff --git a/gridfinity_baseplate.scad b/gridfinity_baseplate.scad
index c2adf10..e9dc639 100644
--- a/gridfinity_baseplate.scad
+++ b/gridfinity_baseplate.scad
@@ -25,7 +25,7 @@ module base_lid(num_x, num_y) {
   
   translate([0, 0, 7]) frame_plain(xsize, ysize, trim=0.25);
   difference() {
-    grid_block(xsize, ysize, 1, magnet_diameter=0, screw_depth=0);
+    grid_block(num_x, num_y, 1, magnet_diameter=0, screw_depth=0);
     gridcopy(num_x, num_y) {
       cornercopy(magnet_position) {
         translate([0, 0, 7-magnet_thickness])
@@ -76,4 +76,4 @@ module frame_plain(num_x, num_y, extra_down=0, trim=0) {
     translate([0, 0, trim ? 0 : -0.01]) 
     render() gridcopy(num_x, num_y) pad_oversize(margins=1);
   }
-}
\ No newline at end of file
+}