diff --git a/Panels/luther_triangle_10hp.scad b/Panels/luther_triangle_10hp.scad
index b4dd892..5288dc7 100644
--- a/Panels/luther_triangle_10hp.scad
+++ b/Panels/luther_triangle_10hp.scad
@@ -33,7 +33,7 @@ $fn=FN;
 // Height of module (mm) - Would not change this if you are using Eurorack
 height = 128.5; // A little less then 3U
 // Thickness of module (mm) - Would not change this if you are using Eurorack
-thickness = 2;  // Website specifies a thickness of 2mm
+thickness = 2;  // Website specifies a thickness of 2mm - but adjust to fit printer specs - often the first layer will be thinner than this
 
 // for inset labels, translating to this height controls label depth
 label_inset_height =  thickness-1;
@@ -53,6 +53,8 @@ hole_dist_side = hp_mm(1.5);
 // Hole distance from the top (mm)
 hole_dist_top = 2.5;
 
+rail_clearance = 9;  // mm from very top/bottom edge and where it is safe to put reinforcing walls; i.e. the thickness of the rail + a safety margin
+
 // margins from edges
 h_margin = hole_dist_side + thickness;
 v_margin = hole_dist_top*2;
@@ -61,14 +63,14 @@ width_mm = hp_mm(width); // where to put the output jacks
 output_column = width_mm - h_margin;
 input_column = h_margin;
 
-working_height = height - v_margin*2 - title_font_size*1.5;
+working_height = height - v_margin*2 - title_font_size;
 working_increment = working_height / 5;
 row_1 = v_margin+12;
 row_2 = working_increment*1 + row_1;
 row_3 = working_increment*2 + row_1;
 row_4 = working_increment*3 + row_1;
 //special-case the top knob
-top_row = height - v_margin - title_font_size*1.5;
+top_row = height - v_margin - title_font_size*2;
 working_width = width_mm - h_margin;
 cv_in = [h_margin, row_1, 0];
 saw_out = [h_margin + working_width/4, row_1, 0];
@@ -88,8 +90,8 @@ c_tune = [width_mm/2, top_row, 0];
 
 f_tune = [h_margin+working_width/8, row_4, 0];
 
-left_rib_x = thickness * 1.2;
-right_rib_x = width_mm - thickness*2.2;
+left_rib_x = thickness * 1;
+right_rib_x = width_mm - thickness*2;
 
 // draw panel, subtract holes
 union() {
@@ -108,12 +110,12 @@ union() {
         translate(pwm_in) audio_jack_3_5mm(); // PWM duty in
 
         // pots
-        translate(fm_lvl) pot_p160(); // fm lvl
-        translate(pwm_duty) pot_p160(); // pwm duty
-        translate(pwm_cv_lvl) pot_p160(); // pwm lvl
+        translate(fm_lvl) pot_p160(anchor_hole="both"); // fm lvl
+        translate(pwm_duty) pot_p160(anchor_hole="both"); // pwm duty
+        translate(pwm_cv_lvl) pot_p160(anchor_hole="both"); // pwm lvl
 
-        translate(c_tune) pot_p160(); // coarse tuning
-        translate(f_tune) pot_p160(); // fine tuning
+        translate(c_tune) pot_p160(anchor_hole="both"); // coarse tuning
+        translate(f_tune) pot_p160(anchor_hole="both"); // fine tuning
 
 /*
         translate([61,height-title_font_size*1.67,label_inset_height]) 
@@ -147,30 +149,30 @@ union() {
     // label the whole thing?
 //    translate([width_mm/2, height-hole_dist_top-10, 0]) label("Fireball VCO", size=10);
 
-    // ribs?
-    //color([.1,.1,.1])
-    translate([left_rib_x, hole_dist_top+4, 0]) wall(h=4, w=height-hole_dist_top*3-4);
-    //color([.1,.1,.1])
-    translate([right_rib_x, hole_dist_top+4, 0]) wall(h=4, w=height-hole_dist_top*3-4);
+    // ribs
+    translate([left_rib_x, rail_clearance, 0])
+        v_wall(h=4, l=height-rail_clearance*2-thickness);
+    translate([right_rib_x, rail_clearance, 0])
+        v_wall(h=4, l=height-rail_clearance*2-thickness);
 
-    // top/bottom ribs?
-    translate([width_mm-hole_dist_top, hole_dist_top+4, 0])
-    rotate([0,0,90])
-    wall(h=4, w=width_mm-hole_dist_top-4);
+    // top horizontal rib
+    translate([left_rib_x, height-rail_clearance-thickness, 0])
+        h_wall(h=4, l=right_rib_x);
 
-    translate([width_mm-hole_dist_top, height-hole_dist_top-4.5, 0])  //4.5?
-    rotate([0,0,90])
-    wall(h=4, w=width_mm-hole_dist_top-4);
+    // middle horizontal rib
+    translate([left_rib_x, top_row-rail_clearance, 0])
+        h_wall(h=4, l=right_rib_x);
 
+    // bottom horizontal rib
+    translate([left_rib_x, rail_clearance, 0])
+        h_wall(h=4, l=right_rib_x);
+
+    // one more vertical to mount the circuit board to, dead center
+    translate([width_mm/2-thickness/2, rail_clearance, 0])
+    v_wall(h=4, l=top_row-rail_clearance*2);
     
-    translate([hole_dist_top, top_row-12, 0])
-    v_wall(h=4, w=width_mm-hole_dist_top*2);
-
-
-    // one more to mount the circuit board to, dead center
-    //color([.1,.1,.1])
-    translate([width_mm/2-thickness/2, hole_dist_top+4, 0])
-    wall(h=6, w=top_row-16.5);
+    translate([width_mm/2-thickness/2+1.15/2, rail_clearance, 0])
+    pcb_holder(h=10, l=top_row-rail_clearance*2, th=1.15, wall_thickness=1);
 
 //    color([1,0,0])
 //    translate([62,height-10,thickness-.1])
@@ -252,10 +254,15 @@ module toggle_switch_6_8mm() {
     translate([0, 0, -1]) cylinder(r=3.4, h=thickness*2+1);
 }
 // http://www.mouser.com/ds/2/414/Datasheet_RotaryPanelPot_P160series-1133272.pdf
-module pot_p160() {
+module pot_p160(anchor_hole="left") {
     translate([0, 0, -1]) cylinder(r=3.75, h=thickness*2);
     // hole for anchor; with translate() ends up being h-1 deep
-    translate([7.8, 0, -1]) cylinder(r=1.5, h=thickness);
+    if (anchor_hole=="left" || anchor_hole=="both") {
+        translate([7.8, 0, -1]) cylinder(r=1.5, h=thickness);
+    }
+    if (anchor_hole=="right" || anchor_hole=="both") {
+        translate([-7.8, 0, -1]) cylinder(r=1.5, h=thickness);
+    }
 }
 
 module pot_wh148() {
@@ -277,14 +284,32 @@ module title(string, size=12, halign="center", font=font_for_title) {
     text(string, size, halign=halign, font=font);
 }
 
-// draw a "vertical" wall to mount a circuit board sideways on
-// h = z height, e.g. height of the board
-module wall(h, w) {
-    translate([0, 0, -h]) cube(size = [thickness, w, h]);
+// draw a "vertical" wall
+// h = z height, i.e. how tall the wall is coming out of the panel
+// l = length of the wall along the panel
+module v_wall(h, l, th=thickness) {
+    translate([0, 0, -h]) cube(size = [th, l, h]);
 }
 
-module v_wall(h, w) {
-    translate([0, 0, -h]) cube(size = [w, thickness, h]);
+// draw a horizontal wall (across the panel)
+// h = z height, how far the wall comes out of the panel
+// l = length of the wall along the panel
+module h_wall(h, l, th=thickness) {
+    translate([0, 0, -h]) cube(size = [l, th, h]);
+}
+
+// draws two walls in parallel, close together so a PCB can fit between
+// h = how deep to make the walls; a little extra is probably good
+// l = length of the side of the board that will be seated in the slit, with tolerances
+// th = thickness of the PCB, with tolerances
+// wall_thickness = how thick to make each wall of the holder
+// e.g.: Radio Shaek is 51mm x 70mm and 1.2mm thick
+module pcb_holder(h, l, th, wall_thickness=thickness) {
+    translate([0-(wall_thickness+th)/2, 0, 0])
+    v_wall(h, l, wall_thickness);
+
+    translate([(wall_thickness+th)/2, 0, 0])
+    v_wall(h, l, wall_thickness);
 }
 
 
diff --git a/Panels/luther_triangle_10hp_pcb_holder.stl b/Panels/luther_triangle_10hp_pcb_holder.stl
new file mode 100644
index 0000000..86b55a8
Binary files /dev/null and b/Panels/luther_triangle_10hp_pcb_holder.stl differ