+// properties of the knives
+nknives = 3;
+widths = [15.5, 15.8, 19.0];
+handlelenbase = 75;
+handlelendelta = [-15, 0, 10];
+locations = [-35, 0, 37];
+bladew = 5; // 2.5
+maxhandledepth = 45;
+
+templatescale = 27.2 / 19.6;
+
+coverlonglen = 120; // xxx
+covershortlen = 70; // xxx
+
+// other tuneables
+front = 5;
+back = 5;
+height = 50;
+minsidein = 4;
+minsideout = 4;
+
+frontbackslop = 0.25;
+
+knifewidthslop = 2.0;
+
+screwbackdepth = 6.0 - 1.0;
+screwdia = 4.0 + 0.5;
+screwcsinkdia = 9.8 + 1.0;
+
+screwabove = 15;
+
+coverthick = 2.4;
+coverside = coverthick;
+
+covertopwing = 15;
+covertopwingbase = 20;
+coveredge = 3;
+
+holesize = 12.5;
+holestrut = 7;
+holeedge = 4;
+
+holeoffx = 0.33;
+holeoffy = 0.23;
+
+indentdepth = 1;
+indentoutersize = holesize + 2.15;
+indentinnersize = indentoutersize - indentdepth * 3.0;
+
+pegstem = 3.5;
+peghead = 10;
+pegstemheight = 2;
+pegheight = 9;
+peglen = 12;
+
+recessblockwidth = peghead + pegstem*3;
+recessblockheight = peglen/2 + pegstem*1.5;
+
+pegsloph = 0.5;
+pegslopv = 0.5;
+pegslopl = 0.5;
+
+pegdepthproportion = 0.80;
+
+// computed
+
+function width(k) = widths[k] + knifewidthslop;
+
+side = minsidein + screwcsinkdia + minsideout;
+totaldepth = front + maxhandledepth + back;
+
+minkx = locations[0] - width(0) /2;
+maxkx = locations[nknives-1] + width(nknives-1)/2;
+
+minx = minkx - side;
+maxx = maxkx + side;
+
+holepitch = holesize+holestrut;
+
+pegrecess = pegdepthproportion*totaldepth - 0.5*peglen;
+
+module ImportTemplate(w,k,t) {
+ fn = str("knifeblock-knives-t",k,t,".dxf");
+ echo(fn);
+ translate([0,0, -w/2])
+ linear_extrude(height=w)
+ scale(templatescale) import(file=fn, convexity=100);
+}
+
+module Knife(k){
+ ImportTemplate(bladew, k,"bl");
+ hull(){
+ ImportTemplate(width(k), k,"hl");
+ translate([-100,0,0])
+ ImportTemplate(width(k), k,"hl");
+ }
+}
+
+module DoKnife(k){
+ translate([locations[k],0,0]){
+ rotate([0,90,0])
+ translate([-(handlelenbase + handlelendelta[k]),0,0])
+ Knife(k);
+ }
+}
+
+module DoKnives(){
+ for (k=[0:nknives-1])
+ DoKnife(k);
+}
+
+module ScrewHole(){
+ translate([0,-50,0])
+ rotate([-90,0,0])
+ cylinder(r=screwdia/2, h=150, $fn=40);
+ translate([0, totaldepth-front - screwbackdepth, 0])
+ rotate([90,0,0])
+ cylinder(r=screwcsinkdia/2 / (sqrt(3)/2), h=100, $fn=6);
+}
+
+module PegTemplate(apex){
+ for (mx=[0,1]) for (my=[0,1]) {
+ mirror([mx,0,0]) mirror([0,my,0])
+ polygon([[-0.1, -0.1],
+ [pegstem/2, -0.1],
+ [pegstem/2, pegstemheight/2],
+ [peghead/2, pegheight /2],
+ [-0.1, pegheight /2 + apex]]);
+ }
+}
+
+module AtSides(){
+ translate([minx,0,0]) child(0);
+ translate([maxx,0,0]) mirror([1,0,0]) child(1);
+}
+
+module BlockPegSlot(){
+ translate([recessblockwidth/2, pegrecess - peglen, -height]){
+ rotate([-90,0,0]) linear_extrude(height=totaldepth){
+ PegTemplate(peghead/2 * 1.2);
+ }
+ }
+}
+
+module DecorativeIndents(){
+ translate([0, -front, 0])
+ rotate([90,0,0])
+ HexGrid(-height, 0, minx,maxx) {
+ hull(){
+ translate([0, 0, -indentdepth])
+ cylinder(r=indentinnersize/2, h=indentdepth, $fn=40);
+ cylinder(r=indentoutersize/2, h=indentdepth, $fn=40);
+ }
+ }
+}
+
+module Block(){
+ sidemidx = minsideout + screwcsinkdia/2;
+
+ difference(){
+ mirror([0,0,1]) {
+ translate([minx, -front, 0])
+ cube([maxx-minx, totaldepth, height]);
+ }
+ for (x=[minx + sidemidx, maxx - sidemidx]) {
+ translate([x, 0, -screwabove])
+ ScrewHole();
+ }
+ for (yshift=[-1,1])
+ translate([0, yshift * frontbackslop, 0])
+ DoKnives();
+ AtSides() { BlockPegSlot(); BlockPegSlot(); }
+ DecorativeIndents();
+ }
+}
+
+module BlockPrint(){ ////toplevel
+ rotate([0,0,90])
+ Block();
+}
+
+module CoverTemplate(){
+ linear_extrude(height=coverthick)
+ polygon([[minx, 0],
+ [maxx, 0],
+ [maxx, coverlonglen+0.1],
+ [maxx - coverside, coverlonglen+0.1],
+ [minx, covershortlen+0.1]]);
+}
+
+module CoverSide(len){
+ translate([0, 0 ,0]) {
+ rotate([90,0,90])
+ linear_extrude(height=coverside)
+ polygon([[0, 0],
+ [0, totaldepth],
+ [covertopwing, totaldepth],
+ [covertopwingbase, coverside + coverthick],
+ [len - covertopwingbase, coverside + coverthick],
+ [len - covertopwing, totaldepth],
+ [len, totaldepth],
+ [len, 0]]);
+ cube([recessblockwidth, recessblockheight, totaldepth]);
+ }
+}
+
+module Peg(){
+ echo("peg angle slope (must be <1)",
+ (peghead-pegstem)/(pegheight-pegstemheight));
+ dx = pegsloph;
+ dy = pegslopv;
+ rotate([90,0,0]) {
+ linear_extrude(height=peglen-pegslopl) {
+ intersection(){
+ translate([-dx,-dy,0]) PegTemplate(0);
+ translate([-dx,+dy,0]) PegTemplate(0);
+ translate([+dx,+dy,0]) PegTemplate(0);
+ translate([+dx,-dy,0]) PegTemplate(0);
+ }
+ }
+ }
+}
+
+module CoverPegSlot(coverlen){
+ translate([recessblockwidth/2, 0, -1]){
+ linear_extrude(height= 1 + pegrecess + 0.5*peglen){
+ PegTemplate(0);
+ }
+ }
+}
+
+module HolesScope(){
+ intersection_for (dx=[-1,+1]) {
+ intersection_for (dy=[-1,+1]) {
+ translate([dx * holeedge, dy * holeedge, -5])
+ scale([1,1,10])
+ CoverTemplate();
+ }
+ }
+}
+
+module HexGrid(xa,xb,ya,yb) {
+ imin = floor(xa / holepitch);
+ imax = ceil(xb / holepitch);
+ jmin = floor(ya / (sqrt(3)*holepitch));
+ jmax = ceil(yb / (sqrt(3)*holepitch));
+ echo("HexGrid ",imin,imax,jmin,jmax);
+ for (i=[imin:imax]) {
+ for (j=[jmin:jmax]) {
+ translate([(j * sqrt(3) + holeoffx) * holepitch,
+ (i + 0.5 + holeoffy) * holepitch,
+ 0]) {
+ child();
+ translate([sqrt(3)/2 * holepitch, -0.5 * holepitch, 0])
+ child();
+ }
+ }
+ }
+}
+
+module Hole(){
+ cylinder(r=holesize/2, h=40, $fn=40);
+}
+
+module Holes(){
+ intersection(){
+ translate([0, 0, -20])
+ HexGrid(0, coverlonglen, minx, maxx)
+ Hole();
+ HolesScope();
+ }
+}
+
+module CoverCover(){
+ difference(){
+ CoverTemplate();
+ Holes();
+ }
+}
+
+module Cover(){
+ difference(){
+ union(){
+ CoverCover();
+ AtSides() { CoverSide(covershortlen); CoverSide(coverlonglen); }
+ }
+ AtSides() { CoverPegSlot(); CoverPegSlot(); }
+ }
+}
+
+module CoverAligned(){
+ translate([0,-front,-height])
+ rotate([-90,0,0])
+ Cover();
+}
+
+module DemoPeg(){
+ translate([recessblockwidth/2, pegrecess, -height])
+ Peg();
+}
+
+module Demo(){ ////toplevel
+ %Block();
+ DoKnives();
+ color([0,0,1]) CoverAligned();
+ color([1,0,0]) AtSides() { DemoPeg(); DemoPeg(); }
+}
+
+module Pegs(){ ////toplevel
+ Peg();
+ translate([-peghead-3, 0,0]) Peg();
+}
+
+module CoverParts(){ ////toplevel
+ Cover();
+ translate([0, coverlonglen, pegheight/2-pegslopv])
+ Pegs();
+}
+
+module FrontDemo(){ ////toplevel
+ color([1,0,1]) Block();
+ color([1,0,1]) CoverAligned();
+ color([0,0,0]) DoKnives();