start to move the TSS lysimeter design to openscad

TSS_lysimeter/SS_lysimeter.scad

+// parameters for final rendering
+//$fa = 1;
+//$fs = 0.4;
+
+bottom_plate_radius = 105;
+bottom_plate_height = 5;
+bottom_plate_edge_height = 5.2;
+bottom_plate_edge_thickness = 4.8;
+bottom_plate_slot_depth = 2;
+bottom_plate_slot_width = 3.6;
+bottom_plate_hole_radius = 10;
+
+// bottom plate design
+
+union(){
+    difference(){
+        // the plate
+        cylinder(h=bottom_plate_height, r=bottom_plate_radius, center = true);
+        //body slot
+        difference(){
+            translate([0,0,bottom_plate_height-bottom_plate_slot_depth])
+                cylinder(h=bottom_plate_slot_depth, r =bottom_plate_radius - bottom_plate_edge_thickness, center = true);
+            translate([0,0,bottom_plate_height-bottom_plate_slot_depth])
+                cylinder(h=bottom_plate_slot_depth, r =bottom_plate_radius - bottom_plate_edge_thickness - bottom_plate_slot_width, center = true);
+        }
+        //holes in the bottom plate
+        cylinder(h = bottom_plate_height, r = bottom_plate_hole_radius, center = true);
+
+        for (i=[1:1:2]){
+            n = 8 +(i-1)*6;
+            step = 360/n;
+            r = 40*i;
+            for (angle=[0:step:359]){
+                dx = r*cos(angle);
+                dy = r*sin(angle);
+                translate([dx,dy,0])
+                    cylinder(h = bottom_plate_height, r = bottom_plate_hole_radius, center = true);
+            }
+        } 
+    }
+    
+
+    // the edge
+    difference(){
+        translate([0,0,bottom_plate_height])
+            cylinder(h=bottom_plate_edge_height, r=bottom_plate_radius,center = true);
+        translate([0,0,bottom_plate_height])    
+            cylinder(h=bottom_plate_edge_height, r=bottom_plate_radius - bottom_plate_edge_thickness, center = true);
+    }
+}
+