diff --git a/assembly.scad b/assembly.scad
index abc554b..6a587f1 100644
--- a/assembly.scad
+++ b/assembly.scad
@@ -1,10 +1,40 @@
 use <supports.scad>;
 use <plate.scad>;
 
-for(x=[0:3]) {
-    for(y=[0:1])
-        translate([60*x,60*y,0])
-            plate4x4(thickness=4);
+pcb_size = 60; // the PCB is 60x60mm square
+pcb_depth = 7.57; // the PCB is 7.57mm deep, overall (including connector + lEDs)
+connector_depth=5.7; // the connector on the bottom of the PCB is 5.8mm thick.
+pcb_thickness= 1.7; // the PCB itself (just the board, w/o components) is roughly 1.7mm thick
+
+pcbs_long = 4;
+pcbs_wide = 2;
+
+wall_width = 5; // width of walls above the top of the supports
+
+support_depth=10; // depth of support structure wall
+tolerance = 0.4;
+
+wall_height = (pcb_depth-connector_depth)+4; // height of walls above the top of the supports
+
+rotate([180,0,0]) {
+    translate([pcb_size/2,-pcb_size/2-pcb_size, -support_depth-pcb_thickness]) {
+        for(x=[0:pcbs_long-1]) {
+            for(y=[0:pcbs_wide-1]) {
+                translate([pcb_size*x,pcb_size*y,0]) {
+                   //%import("pcb-single.stl");
+                }
+            }
+        }
+    }
 }
 
-box();
\ No newline at end of file
+intersection() {
+    translate([-wall_width-tolerance,-wall_width-tolerance,0])
+        cube([wall_width+tolerance+pcb_size,wall_width+tolerance+pcb_size,50]);
+    union() {
+        box();
+        translate([0,0,wall_height+support_depth]) {
+            color("red") plate();
+        };
+    }
+}
\ No newline at end of file
diff --git a/plate.scad b/plate.scad
index d1e7bea..dd087b0 100644
--- a/plate.scad
+++ b/plate.scad
@@ -1,8 +1,28 @@
 // this SCAD file defines the top plate for the case of a neotrellis monome-compatible grid controller.
 // the file is designed to be parametric, for easier testing.
-// TODO tolerances
 // first, we declare some parameters, that will be useful to tweak while testing the model:
 
+pcb_size = 60; // the PCB is 60x60mm square
+pcb_depth = 7.57; // the PCB is 7.57mm deep, overall (including connector + lEDs)
+connector_depth=5.7; // the connector on the bottom of the PCB is 5.8mm thick.
+pcb_thickness= 1.7; // the PCB itself (just the board, w/o components) is roughly 1.7mm thick
+
+support_width=5; // width of support structure walls
+support_depth=10; // depth of support structure wall
+floor_depth = 1; // depth of the bottom floor of the support
+
+wall_height = (pcb_depth-connector_depth)+4; // height of walls above the top of the supports
+wall_width = 5; // width of walls above the top of the supports
+
+cutout_width=25; // width of the cutouts in the support structure, for wires etc
+cutout_depth=5; // depth of the cutouts in the support structure
+
+pcbs_wide=2; // how many trellis PCBs are in the grid, width-wise
+pcbs_long=4; // how many trellis PCBs are in the grid, length-wise
+
+hole_size = 4; // size of the holes in which the top plate pegs sit
+hole_depth = 15; // depth of the holes in which the top plate pegs sit
+
 // Button size (in mm)
 button_size = 10;
 // Spacing between buttons (in mm)
@@ -12,23 +32,49 @@ tolerance = 0.4;
 // outer spacing - spacing between the edge of the silicon part and the buttons
 outer_spacing = 2.5;
 
-// module for a 4x4 unit of the top plate.
-module plate4x4(thickness) {
+plate_thickness = 4;
+
+// module for the entire plate
+module plate() {
     difference() {
-        cube(
-        [outer_spacing*2+button_size*4+spacing*3,
-         outer_spacing*2+button_size*4+spacing*3,
-        thickness]);
-        for(x=[0:3]) {
-            for(y=[0:3]) {
-            translate(
-                [outer_spacing-(tolerance/2)+((button_size+spacing)*x),
-                outer_spacing-(tolerance/2)+((button_size+spacing)*y),
-                -0.5])
-                cube([button_size+tolerance,button_size+tolerance,thickness+1]);
+        translate([-(wall_width+tolerance),-(wall_width+tolerance)]) {
+                cube(
+                [pcb_size*pcbs_long+(wall_width+tolerance)*2,
+                pcb_size*pcbs_wide+(wall_width+tolerance)*2,
+                plate_thickness]);
+        }
+        for(x=[0:pcbs_long-1]){
+            for(y=[0:pcbs_wide-1]) {
+                translate([x*pcb_size,y*pcb_size,0])
+                    plate4x4(plate_thickness);
             }
         }
     }
+        // mounting pegs 
+       translate([-tolerance-wall_width/2,-tolerance-wall_width/2,-plate_thickness]){
+           cube([hole_size-tolerance,hole_size-tolerance,hole_depth], center=true);
+       }
+       translate([tolerance+wall_width/2+(pcbs_long*pcb_size),-tolerance-wall_width/2,-plate_thickness]){
+           cube([hole_size-tolerance,hole_size-tolerance,hole_depth], center=true);
+       }
+       translate([tolerance+wall_width/2+(pcbs_long*pcb_size),tolerance+wall_width/2+(pcbs_wide*pcb_size),-plate_thickness]){
+           cube([hole_size-tolerance,hole_size-tolerance,hole_depth], center=true);
+       }
+       translate([-tolerance-wall_width/2,tolerance+wall_width/2+(pcbs_wide*pcb_size),-plate_thickness]){
+           cube([hole_size-tolerance,hole_size-tolerance,hole_depth], center=true);
+       }
+}
+// module for the holes in a 4x4 unit of the top plate.
+module plate4x4(thickness) {
+    for(x=[0:3]) {
+        for(y=[0:3]) {
+        translate(
+            [outer_spacing-(tolerance/2)+((button_size+spacing)*x),
+            outer_spacing-(tolerance/2)+((button_size+spacing)*y),
+            -0.5])
+            cube([button_size+tolerance,button_size+tolerance,thickness+1]);
+        }
+    }
 }
 
-plate4x4(1);
\ No newline at end of file
+plate();
\ No newline at end of file
diff --git a/supports.scad b/supports.scad
index 8bec631..487ca2c 100644
--- a/supports.scad
+++ b/supports.scad
@@ -33,7 +33,7 @@ rotate([180,0,0]) {
         for(x=[0:pcbs_long-1]) {
             for(y=[0:pcbs_wide-1]) {
                 translate([pcb_size*x,pcb_size*y,0]) {
-                //   %import("pcb-single.stl");
+                   %import("pcb-single.stl");
                 }
             }
         }
@@ -69,7 +69,7 @@ module box() {
             // create large outer box
             translate([-(wall_width+tolerance),-(wall_width+tolerance)]) {
                 difference() {
-                    // outer cute
+                    // outer cube
                     cube(
                     [pcb_size*pcbs_long+(wall_width+tolerance)*2,
                     pcb_size*pcbs_wide+(wall_width+tolerance)*2,