tube-crossdrill-jig.scad

   1 // -*- C -*-
   2
   3 //$fs=0.1;
   4 //$fa=3;
   5 $fs=0.2;
   6 $fa=6;
   7
   8 rearwallthick = 3;
   9 basethick = 2;
  10 mainframeendthick = 2.5;
  11
  12 tubedia = 16 + 0.8;
  13 tubetubethick=2;
  14 tubetubetopslop=1;
  15
  16 boltholedia = 6.5 + 0.5;
  17 boltholeslotshorter = 6;
  18 mainframeholedia = 5 + 0.5;
  19
  20 // "slot" refers to the things in the base of the drill press stand
  21 backslotedgespace = 55;
  22 slotwidth = 11.5;
  23 backslotmid2screwhole = 17;
  24 slotplugheight = 5.5;
  25 slotplugshorterlen = 8;
  26 slotpluglongerlen = 18;
  27
  28 slotslope = 11.0 / 18.5;
  29
  30 // "keepslot" refers to the screws in the wooden jig block
  31 keepslotstartz = 20;
  32 keepslotlen = 25;
  33 keepslotx = backslotedgespace / 2;
  34 keepslotwidth = 4;
  35
  36 mainframeextraside = 15;
  37 mainframeextrafront = 15;
  38
  39 rearwallstrengthwidth = 10;
  40 keepslotclear = 10;
  41
  42 // computed values
  43
  44 slotslopediag = sqrt(1 + slotslope*slotslope);
  45 slotwidthx = slotwidth * slotslopediag;
  46
  47 slotxperlen = slotslope / slotslopediag;
  48 slotyperlen =         1 / slotslopediag;
  49
  50 mainframeholex = backslotedgespace/2 + slotwidth/sqrt(2) +
  51   backslotmid2screwhole / sqrt(2);
  52
  53 mainframeholey = -backslotmid2screwhole / sqrt(2);
  54
  55 mainframemaxx = mainframeholex + mainframeextraside;
  56 mainframeminy = mainframeholey - mainframeextrafront;
  57 mainframemaxz = keepslotstartz + keepslotlen;
  58
  59 module MainFrame(){
  60   for (m=[0,1]) {
  61     mirror([m,0,0]) {
  62       translate([-1, mainframeminy, 0])
  63         cube([mainframemaxx+1, -mainframeminy, basethick]);
  64       translate([-1, -rearwallthick, 0])
  65         cube([mainframemaxx+1, rearwallthick, mainframemaxz]);
  66
  67       for (x=[keepslotx - keepslotclear, mainframemaxx - 0.5]) {
  68         translate([x,0,0])
  69           rotate([90,0,-90])
  70           linear_extrude(height=mainframeendthick)
  71           polygon([[-mainframeminy, 0],
  72                    [0, mainframemaxz],
  73                    [0, 0]]);
  74       }
  75
  76       translate([backslotedgespace/2, 0, 1])
  77         mirror([0,0,1])
  78         linear_extrude(height=slotplugheight+1)
  79         polygon([[0,0],
  80                  [slotwidthx, 0],
  81                  [slotwidthx + slotplugshorterlen * slotxperlen,
  82                   -slotplugshorterlen * slotyperlen],
  83                  [slotpluglongerlen * slotxperlen,
  84                   -slotpluglongerlen * slotyperlen]]);
  85       translate([-1,
  86                  -rearwallthick - boltholeslotshorter + 0.2,
  87                  tubedia + tubetubetopslop + tubetubethick + 4])
  88         cube([keepslotx - keepslotclear + 1,
  89               boltholeslotshorter + 0.5,
  90               rearwallstrengthwidth]);
  91     }
  92   }
  93 }
  94
  95 module TubeThing(extralen, dia, extraheight, underheight){
  96   effheight = tubetubetopslop + extraheight + underheight;
  97   len = -mainframeminy + extralen * 2;
  98   translate([0, mainframeminy - extralen, -underheight]) {
  99     translate([0,0, dia/2 + effheight])
 100       rotate([-90,0,0]) cylinder(h=len, r=dia/2);
 101     translate([-dia/2, 0, 0])
 102       cube([dia, len, effheight + dia/2]);
 103   }
 104 }
 105
 106 module Jig(){
 107   difference(){
 108     union(){
 109       MainFrame();
 110       TubeThing(0, tubedia+tubetubethick*2, -tubetubethick, 0);
 111     }
 112     union(){
 113       translate([0,0,-0.1])
 114         TubeThing(10, tubedia, 0, 5);
 115       translate([-boltholedia/2, mainframeminy - 1, -5])
 116         cube([boltholedia,
 117               -mainframeminy + 1 - rearwallthick - boltholeslotshorter,
 118               mainframemaxz + 10]);
 119       for (m=[0,1]) {
 120         mirror([m,0,0]) {
 121           translate([mainframeholex, mainframeholey, -30])
 122             cylinder(h=basethick+40, r=mainframeholedia/2);
 123           translate([keepslotx - keepslotwidth/2,
 124                      -10, keepslotstartz])
 125             cube([keepslotwidth, 20, keepslotlen + 10]);
 126         }
 127       }
 128     }
 129   }
 130 }
 131
 132 //MainFrame();
 133 //TubeThing(0, tubedia);
 134
 135 rotate([-90,0,0])
 136   Jig();