models contain brim

README.md

@@ -1,6 +1,6 @@
 # lampshades models
 
-My lampshade on the Ikea lamp is similar to [HEKTOGRAM](https://www.ikea.com/cz/cs/p/hektogram-stojaci-cteci-lampa-stribrna-bila-80477710/) was broken. As a owner of 3D printing I tried to make new lapmshade.
+My lampshade on the stand lamp [Eglo 93917](https://www.eglo.cz/katalog/interierova-svitidla/stojaci/93917-up-2) was broken. As a owner of 3D printing I tried to make new lapmshade.
 
 I have two versions of lampshades; both are made in amazing [OpenSCAD](https://openscad.org) and are fully customizable.
 
@@ -14,6 +14,8 @@ My first models contain nuts as part of lampshade, but it wasn't a good design,
 
 Thanks to decision to separate lampshade and nut (the original set up of the lamp btw.) I'm fully flexible.
 
+Models contain brims to support hold on the printing plate. You must cut the brim before installation.
+
 I wish you a lot of fun with modeling (and printing).
 
 ## how to install dependencies for nut?

lampshade_conical.scad

@@ -3,6 +3,9 @@ bottom_d = 44;
 top_d = 170;
 facets = 40;
 
+bottom_brim_thickness = 20;
+bottom_brim_height = 2;
+
 bottom_r=bottom_d/2;
 top_r=top_d/2;
 thickness=2;
@@ -11,4 +14,11 @@ difference() {
 cylinder(height, bottom_r, top_r, $fn=facets);
 translate([0,0,-0.01])
     cylinder(height+0.02, bottom_r-thickness, top_r-thickness, $fn=facets);
+}
+
+// brim
+difference() {
+    cylinder(1, bottom_d/2+bottom_brim_thickness, bottom_d/2+bottom_brim_thickness);
+    translate([0,0,-0.01])
+    cylinder(bottom_brim_height+0.02, bottom_d/2, bottom_d/2);
 }

lampshade_curved.scad

@@ -3,6 +3,12 @@ thickness = 2;
 top_d = 179;
 bottom_d = 44;
 
+bottom_brim_thickness = 20;
+bottom_brim_height = 2;
+
+start_of_bottom = (bottom_d/2)^2/curved_factor;
+
+translate([0,0,-start_of_bottom])
 difference() {
     rotate_extrude($fn=200)
     difference() {
@@ -12,6 +18,13 @@ difference() {
     cylinder(top_d, bottom_d/2, bottom_d/2);
 }
 
+// brim
+difference() {
+    cylinder(1, bottom_d/2+bottom_brim_thickness, bottom_d/2+bottom_brim_thickness);
+    translate([0,0,-0.01])
+    cylinder(bottom_brim_height+0.02, bottom_d/2, bottom_d/2);
+}
+
 function point(i, R) = [
   i,
   i*i/R
@@ -20,6 +33,6 @@ function point(i, R) = [
 function bowl(height, x) = (
  concat(
     [ for (i = [0:1:height]) point(i, x) ],
-    [[0,height*height/x]]
+    [[0,height^2/x]]
  )
 );

nut.scad

@@ -1,7 +1,7 @@
 use <threadlib/threadlib.scad>
 
-turns = 2;
+turns = 1;
-bottom_d = 70;
+bottom_d = 85;
 diameter = 42;
 len_between_threads = 3;
 holder_height = 5;