My self designed awesome 3D printer
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Pulley_T-MXL-XL-HTD-GT2_N-tooth.scad 18KB

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  1. // Parametric Pulley with multiple belt profiles
  2. // by droftarts January 2012
  3. // Based on pulleys by:
  4. // http://www.thingiverse.com/thing:11256 by me!
  5. // https://github.com/prusajr/PrusaMendel by Josef Prusa
  6. // http://www.thingiverse.com/thing:3104 by GilesBathgate
  7. // http://www.thingiverse.com/thing:2079 by nophead
  8. // dxf tooth data from http://oem.cadregister.com/asp/PPOW_Entry.asp?company=915217&elementID=07807803/METRIC/URETH/WV0025/F
  9. // pulley diameter checked and modelled from data at http://www.sdp-si.com/D265/HTML/D265T016.html
  10. /**
  11. * @name Pulley
  12. * @category Printed
  13. * @using 1 x m3 nut, normal or nyloc
  14. * @using 1 x m3x10 set screw or 1 x m3x8 grub screw
  15. */
  16. // retrieved from https://www.thingiverse.com/thing:16627
  17. // tuneable constants
  18. teeth = 20; // Number of teeth, standard Mendel T5 belt = 8, gives Outside Diameter of 11.88mm
  19. profile = 12; // 1=MXL 2=40DP 3=XL 4=H 5=T2.5 6=T5 7=T10 8=AT5 9=HTD_3mm 10=HTD_5mm 11=HTD_8mm 12=GT2_2mm 13=GT2_3mm 14=GT2_5mm
  20. motor_shaft = 5.2; // NEMA17 motor shaft exact diameter = 5
  21. m3_dia = 3.2; // 3mm hole diameter
  22. m3_nut_hex = 1; // 1 for hex, 0 for square nut
  23. m3_nut_flats = 5.7; // normal M3 hex nut exact width = 5.5
  24. m3_nut_depth = 2.7; // normal M3 hex nut exact depth = 2.4, nyloc = 4
  25. retainer = 1; // Belt retainer above teeth, 0 = No, 1 = Yes
  26. retainer_ht = 1.5; // height of retainer flange over pulley, standard = 1.5
  27. idler = 0; // Belt retainer below teeth, 0 = No, 1 = Yes
  28. idler_ht = 1.5; // height of idler flange over pulley, standard = 1.5
  29. pulley_t_ht = 7.3; // length of toothed part of pulley, standard = 12
  30. pulley_b_ht = 7; // pulley base height, standard = 8. Set to same as idler_ht if you want an idler but no pulley.
  31. pulley_b_dia = 16; // pulley base diameter, standard = 20
  32. no_of_nuts = 0; // number of captive nuts required, standard = 1
  33. nut_angle = 90; // angle between nuts, standard = 90
  34. nut_shaft_distance = 1.2; // distance between inner face of nut and shaft, can be negative.
  35. // ********************************
  36. // ** Scaling tooth for good fit **
  37. // ********************************
  38. /* To improve fit of belt to pulley, set the following constant. Decrease or increase by 0.1mm at a time. We are modelling the *BELT* tooth here, not the tooth on the pulley. Increasing the number will *decrease* the pulley tooth size. Increasing the tooth width will also scale proportionately the tooth depth, to maintain the shape of the tooth, and increase how far into the pulley the tooth is indented. Can be negative */
  39. additional_tooth_width = 0.2; //mm
  40. // If you need more tooth depth than this provides, adjust the following constant. However, this will cause the shape of the tooth to change.
  41. additional_tooth_depth = 0; //mm
  42. // calculated constants
  43. nut_elevation = pulley_b_ht/2;
  44. m3_nut_points = 2*((m3_nut_flats/2)/cos(30)); // This is needed for the nut trap
  45. // The following set the pulley diameter for a given number of teeth
  46. MXL_pulley_dia = tooth_spacing (2.032,0.254);
  47. 40DP_pulley_dia = tooth_spacing (2.07264,0.1778);
  48. XL_pulley_dia = tooth_spacing (5.08,0.254);
  49. H_pulley_dia = tooth_spacing (9.525,0.381);
  50. T2_5_pulley_dia = tooth_spaceing_curvefit (0.7467,0.796,1.026);
  51. T5_pulley_dia = tooth_spaceing_curvefit (0.6523,1.591,1.064);
  52. T10_pulley_dia = tooth_spacing (10,0.93);
  53. AT5_pulley_dia = tooth_spaceing_curvefit (0.6523,1.591,1.064);
  54. HTD_3mm_pulley_dia = tooth_spacing (3,0.381);
  55. HTD_5mm_pulley_dia = tooth_spacing (5,0.5715);
  56. HTD_8mm_pulley_dia = tooth_spacing (8,0.6858);
  57. GT2_2mm_pulley_dia = tooth_spacing (2,0.254);
  58. GT2_3mm_pulley_dia = tooth_spacing (3,0.381);
  59. GT2_5mm_pulley_dia = tooth_spacing (5,0.5715);
  60. // The following calls the pulley creation part, and passes the pulley diameter and tooth width to that module
  61. module gt2_pulley() {
  62. if ( profile == 1 ) { pulley ( "MXL" , MXL_pulley_dia , 0.508 , 1.321 ); }
  63. if ( profile == 2 ) { pulley ( "40 D.P." , 40DP_pulley_dia , 0.457 , 1.226 ); }
  64. if ( profile == 3 ) { pulley ( "XL" , XL_pulley_dia , 1.27, 3.051 ); }
  65. if ( profile == 4 ) { pulley ( "H" , H_pulley_dia ,1.905 , 5.359 ); }
  66. if ( profile == 5 ) { pulley ( "T2.5" , T2_5_pulley_dia , 0.7 , 1.678 ); }
  67. if ( profile == 6 ) { pulley ( "T5" , T5_pulley_dia , 1.19 , 3.264 ); }
  68. if ( profile == 7 ) { pulley ( "T10" , T10_pulley_dia , 2.5 , 6.13 ); }
  69. if ( profile == 8 ) { pulley ( "AT5" , AT5_pulley_dia , 1.19 , 4.268 ); }
  70. if ( profile == 9 ) { pulley ( "HTD 3mm" , HTD_3mm_pulley_dia , 1.289 , 2.27 ); }
  71. if ( profile == 10 ) { pulley ( "HTD 5mm" , HTD_5mm_pulley_dia , 2.199 , 3.781 ); }
  72. if ( profile == 11 ) { pulley ( "HTD 8mm" , HTD_8mm_pulley_dia , 3.607 , 6.603 ); }
  73. if ( profile == 12 ) { pulley ( "GT2 2mm" , GT2_2mm_pulley_dia , 0.764 , 1.494 ); }
  74. if ( profile == 13 ) { pulley ( "GT2 3mm" , GT2_3mm_pulley_dia , 1.169 , 2.31 ); }
  75. if ( profile == 14 ) { pulley ( "GT2 5mm" , GT2_5mm_pulley_dia , 1.969 , 3.952 ); }
  76. }
  77. //gt2_pulley();
  78. // Functions
  79. function tooth_spaceing_curvefit (b,c,d)
  80. = ((c * pow(teeth,d)) / (b + pow(teeth,d))) * teeth ;
  81. function tooth_spacing(tooth_pitch,pitch_line_offset)
  82. = (2*((teeth*tooth_pitch)/(3.14159265*2)-pitch_line_offset)) ;
  83. // Main Module
  84. module pulley( belt_type , pulley_OD , tooth_depth , tooth_width )
  85. {
  86. echo (str("Belt type = ",belt_type,"; Number of teeth = ",teeth,"; Pulley Outside Diameter = ",pulley_OD,"mm "));
  87. tooth_distance_from_centre = sqrt( pow(pulley_OD/2,2) - pow((tooth_width+additional_tooth_width)/2,2));
  88. tooth_width_scale = (tooth_width + additional_tooth_width ) / tooth_width;
  89. tooth_depth_scale = ((tooth_depth + additional_tooth_depth ) / tooth_depth) ;
  90. // ************************************************************************
  91. // *** uncomment the following line if pulley is wider than puller base ***
  92. // ************************************************************************
  93. // translate ([0,0, pulley_b_ht + pulley_t_ht + retainer_ht ]) rotate ([0,180,0])
  94. difference()
  95. {
  96. union()
  97. {
  98. //base
  99. if ( pulley_b_ht < 2 ) { echo ("CAN'T DRAW PULLEY BASE, HEIGHT LESS THAN 2!!!"); } else {
  100. rotate_extrude($fn=pulley_b_dia*2)
  101. {
  102. square([pulley_b_dia/2-1,pulley_b_ht]);
  103. square([pulley_b_dia/2,pulley_b_ht-1]);
  104. translate([pulley_b_dia/2-1,pulley_b_ht-1]) circle(1);
  105. }
  106. }
  107. difference()
  108. {
  109. //shaft - diameter is outside diameter of pulley
  110. translate([0,0,pulley_b_ht])
  111. rotate ([0,0,360/(teeth*4)])
  112. cylinder(r=pulley_OD/2,h=pulley_t_ht, $fn=teeth*4);
  113. //teeth - cut out of shaft
  114. for(i=[1:teeth])
  115. rotate([0,0,i*(360/teeth)])
  116. translate([0,-tooth_distance_from_centre,pulley_b_ht -1])
  117. scale ([ tooth_width_scale , tooth_depth_scale , 1 ])
  118. {
  119. if ( profile == 1 ) { MXL();}
  120. if ( profile == 2 ) { 40DP();}
  121. if ( profile == 3 ) { XL();}
  122. if ( profile == 4 ) { H();}
  123. if ( profile == 5 ) { T2_5();}
  124. if ( profile == 6 ) { T5();}
  125. if ( profile == 7 ) { T10();}
  126. if ( profile == 8 ) { AT5();}
  127. if ( profile == 9 ) { HTD_3mm();}
  128. if ( profile == 10 ) { HTD_5mm();}
  129. if ( profile == 11 ) { HTD_8mm();}
  130. if ( profile == 12 ) { GT2_2mm();}
  131. if ( profile == 13 ) { GT2_3mm();}
  132. if ( profile == 14 ) { GT2_5mm();}
  133. }
  134. }
  135. //belt retainer / idler
  136. if ( retainer > 0 ) {translate ([0,0, pulley_b_ht + pulley_t_ht ])
  137. rotate_extrude($fn=teeth*4)
  138. polygon([[0,0],[pulley_OD/2,0],[pulley_OD/2 + retainer_ht , retainer_ht],[0 , retainer_ht],[0,0]]);}
  139. if ( idler > 0 ) {translate ([0,0, pulley_b_ht - idler_ht ])
  140. rotate_extrude($fn=teeth*4)
  141. polygon([[0,0],[pulley_OD/2 + idler_ht,0],[pulley_OD/2 , idler_ht],[0 , idler_ht],[0,0]]);}
  142. }
  143. //hole for motor shaft
  144. translate([0,0,-1])cylinder(r=motor_shaft/2,h=pulley_b_ht + pulley_t_ht + retainer_ht + 2,$fn=motor_shaft*4);
  145. //captive nut and grub screw holes
  146. if ( pulley_b_ht < m3_nut_flats && no_of_nuts > 0) { echo ("CAN'T DRAW CAPTIVE NUTS, HEIGHT LESS THAN NUT DIAMETER!!!"); } else {
  147. if ( (pulley_b_dia - motor_shaft)/2 < m3_nut_depth + 3 && no_of_nuts > 0) { echo ("CAN'T DRAW CAPTIVE NUTS, DIAMETER TOO SMALL FOR NUT DEPTH!!!"); } else if (no_of_nuts > 0) {
  148. for(j=[1:no_of_nuts]) rotate([0,0,j*nut_angle])
  149. translate([0,0,nut_elevation])rotate([90,0,0])
  150. union()
  151. {
  152. //entrance
  153. translate([0,-pulley_b_ht/4-0.5,motor_shaft/2+m3_nut_depth/2+nut_shaft_distance]) cube([m3_nut_flats,pulley_b_ht/2+1,m3_nut_depth],center=true);
  154. //nut
  155. if ( m3_nut_hex > 0 )
  156. {
  157. // hex nut
  158. translate([0,0.25,motor_shaft/2+m3_nut_depth/2+nut_shaft_distance]) rotate([0,0,30]) cylinder(r=m3_nut_points/2,h=m3_nut_depth,center=true,$fn=6);
  159. } else {
  160. // square nut
  161. translate([0,0.25,motor_shaft/2+m3_nut_depth/2+nut_shaft_distance]) cube([m3_nut_flats,m3_nut_flats,m3_nut_depth],center=true);
  162. }
  163. //grub screw hole
  164. rotate([0,0,22.5])cylinder(r=m3_dia/2,h=pulley_b_dia/2+1,$fn=8);
  165. }
  166. }}
  167. }
  168. }
  169. // Tooth profile modules
  170. module MXL()
  171. {
  172. linear_extrude(height=pulley_t_ht+2) polygon([[-0.660421,-0.5],[-0.660421,0],[-0.621898,0.006033],[-0.587714,0.023037],[-0.560056,0.049424],[-0.541182,0.083609],[-0.417357,0.424392],[-0.398413,0.458752],[-0.370649,0.48514],[-0.336324,0.502074],[-0.297744,0.508035],[0.297744,0.508035],[0.336268,0.502074],[0.370452,0.48514],[0.39811,0.458752],[0.416983,0.424392],[0.540808,0.083609],[0.559752,0.049424],[0.587516,0.023037],[0.621841,0.006033],[0.660421,0],[0.660421,-0.5]]);
  173. }
  174. module 40DP()
  175. {
  176. linear_extrude(height=pulley_t_ht+2) polygon([[-0.612775,-0.5],[-0.612775,0],[-0.574719,0.010187],[-0.546453,0.0381],[-0.355953,0.3683],[-0.327604,0.405408],[-0.291086,0.433388],[-0.248548,0.451049],[-0.202142,0.4572],[0.202494,0.4572],[0.248653,0.451049],[0.291042,0.433388],[0.327609,0.405408],[0.356306,0.3683],[0.546806,0.0381],[0.574499,0.010187],[0.612775,0],[0.612775,-0.5]]);
  177. }
  178. module XL()
  179. {
  180. linear_extrude(height=pulley_t_ht+2) polygon([[-1.525411,-1],[-1.525411,0],[-1.41777,0.015495],[-1.320712,0.059664],[-1.239661,0.129034],[-1.180042,0.220133],[-0.793044,1.050219],[-0.733574,1.141021],[-0.652507,1.210425],[-0.555366,1.254759],[-0.447675,1.270353],[0.447675,1.270353],[0.555366,1.254759],[0.652507,1.210425],[0.733574,1.141021],[0.793044,1.050219],[1.180042,0.220133],[1.239711,0.129034],[1.320844,0.059664],[1.417919,0.015495],[1.525411,0],[1.525411,-1]]);
  181. }
  182. module H()
  183. {
  184. linear_extrude(height=pulley_t_ht+2) polygon([[-2.6797,-1],[-2.6797,0],[-2.600907,0.006138],[-2.525342,0.024024],[-2.45412,0.052881],[-2.388351,0.091909],[-2.329145,0.140328],[-2.277614,0.197358],[-2.234875,0.262205],[-2.202032,0.334091],[-1.75224,1.57093],[-1.719538,1.642815],[-1.676883,1.707663],[-1.62542,1.764693],[-1.566256,1.813112],[-1.500512,1.85214],[-1.4293,1.880997],[-1.353742,1.898883],[-1.274949,1.905021],[1.275281,1.905021],[1.354056,1.898883],[1.429576,1.880997],[1.500731,1.85214],[1.566411,1.813112],[1.625508,1.764693],[1.676919,1.707663],[1.719531,1.642815],[1.752233,1.57093],[2.20273,0.334091],[2.235433,0.262205],[2.278045,0.197358],[2.329455,0.140328],[2.388553,0.091909],[2.454233,0.052881],[2.525384,0.024024],[2.600904,0.006138],[2.6797,0],[2.6797,-1]]);
  185. }
  186. module T2_5()
  187. {
  188. linear_extrude(height=pulley_t_ht+2) polygon([[-0.839258,-0.5],[-0.839258,0],[-0.770246,0.021652],[-0.726369,0.079022],[-0.529167,0.620889],[-0.485025,0.67826],[-0.416278,0.699911],[0.416278,0.699911],[0.484849,0.67826],[0.528814,0.620889],[0.726369,0.079022],[0.770114,0.021652],[0.839258,0],[0.839258,-0.5]]);
  189. }
  190. module T5()
  191. {
  192. linear_extrude(height=pulley_t_ht+2) polygon([[-1.632126,-0.5],[-1.632126,0],[-1.568549,0.004939],[-1.507539,0.019367],[-1.450023,0.042686],[-1.396912,0.074224],[-1.349125,0.113379],[-1.307581,0.159508],[-1.273186,0.211991],[-1.246868,0.270192],[-1.009802,0.920362],[-0.983414,0.978433],[-0.949018,1.030788],[-0.907524,1.076798],[-0.859829,1.115847],[-0.80682,1.147314],[-0.749402,1.170562],[-0.688471,1.184956],[-0.624921,1.189895],[0.624971,1.189895],[0.688622,1.184956],[0.749607,1.170562],[0.807043,1.147314],[0.860055,1.115847],[0.907754,1.076798],[0.949269,1.030788],[0.9837,0.978433],[1.010193,0.920362],[1.246907,0.270192],[1.273295,0.211991],[1.307726,0.159508],[1.349276,0.113379],[1.397039,0.074224],[1.450111,0.042686],[1.507589,0.019367],[1.568563,0.004939],[1.632126,0],[1.632126,-0.5]]);
  193. }
  194. module T10()
  195. {
  196. linear_extrude(height=pulley_t_ht+2) polygon([[-3.06511,-1],[-3.06511,0],[-2.971998,0.007239],[-2.882718,0.028344],[-2.79859,0.062396],[-2.720931,0.108479],[-2.651061,0.165675],[-2.590298,0.233065],[-2.539962,0.309732],[-2.501371,0.394759],[-1.879071,2.105025],[-1.840363,2.190052],[-1.789939,2.266719],[-1.729114,2.334109],[-1.659202,2.391304],[-1.581518,2.437387],[-1.497376,2.47144],[-1.408092,2.492545],[-1.314979,2.499784],[1.314979,2.499784],[1.408091,2.492545],[1.497371,2.47144],[1.581499,2.437387],[1.659158,2.391304],[1.729028,2.334109],[1.789791,2.266719],[1.840127,2.190052],[1.878718,2.105025],[2.501018,0.394759],[2.539726,0.309732],[2.59015,0.233065],[2.650975,0.165675],[2.720887,0.108479],[2.798571,0.062396],[2.882713,0.028344],[2.971997,0.007239],[3.06511,0],[3.06511,-1]]);
  197. }
  198. module AT5()
  199. {
  200. linear_extrude(height=pulley_t_ht+2) polygon([[-2.134129,-0.75],[-2.134129,0],[-2.058023,0.005488],[-1.984595,0.021547],[-1.914806,0.047569],[-1.849614,0.082947],[-1.789978,0.127073],[-1.736857,0.179338],[-1.691211,0.239136],[-1.653999,0.305859],[-1.349199,0.959203],[-1.286933,1.054635],[-1.201914,1.127346],[-1.099961,1.173664],[-0.986896,1.18992],[0.986543,1.18992],[1.099614,1.173664],[1.201605,1.127346],[1.286729,1.054635],[1.349199,0.959203],[1.653646,0.305859],[1.690859,0.239136],[1.73651,0.179338],[1.789644,0.127073],[1.849305,0.082947],[1.914539,0.047569],[1.984392,0.021547],[2.057906,0.005488],[2.134129,0],[2.134129,-0.75]]);
  201. }
  202. module HTD_3mm()
  203. {
  204. linear_extrude(height=pulley_t_ht+2) polygon([[-1.135062,-0.5],[-1.135062,0],[-1.048323,0.015484],[-0.974284,0.058517],[-0.919162,0.123974],[-0.889176,0.206728],[-0.81721,0.579614],[-0.800806,0.653232],[-0.778384,0.72416],[-0.750244,0.792137],[-0.716685,0.856903],[-0.678005,0.918199],[-0.634505,0.975764],[-0.586483,1.029338],[-0.534238,1.078662],[-0.47807,1.123476],[-0.418278,1.16352],[-0.355162,1.198533],[-0.289019,1.228257],[-0.22015,1.25243],[-0.148854,1.270793],[-0.07543,1.283087],[-0.000176,1.28905],[0.075081,1.283145],[0.148515,1.270895],[0.219827,1.252561],[0.288716,1.228406],[0.354879,1.19869],[0.418018,1.163675],[0.477831,1.123623],[0.534017,1.078795],[0.586276,1.029452],[0.634307,0.975857],[0.677809,0.91827],[0.716481,0.856953],[0.750022,0.792167],[0.778133,0.724174],[0.800511,0.653236],[0.816857,0.579614],[0.888471,0.206728],[0.919014,0.123974],[0.974328,0.058517],[1.048362,0.015484],[1.135062,0],[1.135062,-0.5]]);
  205. }
  206. module HTD_5mm()
  207. {
  208. linear_extrude(height=pulley_t_ht+2) polygon([[-1.89036,-0.75],[-1.89036,0],[-1.741168,0.02669],[-1.61387,0.100806],[-1.518984,0.21342],[-1.467026,0.3556],[-1.427162,0.960967],[-1.398568,1.089602],[-1.359437,1.213531],[-1.310296,1.332296],[-1.251672,1.445441],[-1.184092,1.552509],[-1.108081,1.653042],[-1.024167,1.746585],[-0.932877,1.832681],[-0.834736,1.910872],[-0.730271,1.980701],[-0.62001,2.041713],[-0.504478,2.09345],[-0.384202,2.135455],[-0.259708,2.167271],[-0.131524,2.188443],[-0.000176,2.198511],[0.131296,2.188504],[0.259588,2.167387],[0.384174,2.135616],[0.504527,2.093648],[0.620123,2.04194],[0.730433,1.980949],[0.834934,1.911132],[0.933097,1.832945],[1.024398,1.746846],[1.108311,1.653291],[1.184308,1.552736],[1.251865,1.445639],[1.310455,1.332457],[1.359552,1.213647],[1.39863,1.089664],[1.427162,0.960967],[1.467026,0.3556],[1.518984,0.21342],[1.61387,0.100806],[1.741168,0.02669],[1.89036,0],[1.89036,-0.75]]);
  209. }
  210. module HTD_8mm()
  211. {
  212. linear_extrude(height=pulley_t_ht+2) polygon([[-3.301471,-1],[-3.301471,0],[-3.16611,0.012093],[-3.038062,0.047068],[-2.919646,0.10297],[-2.813182,0.177844],[-2.720989,0.269734],[-2.645387,0.376684],[-2.588694,0.496739],[-2.553229,0.627944],[-2.460801,1.470025],[-2.411413,1.691917],[-2.343887,1.905691],[-2.259126,2.110563],[-2.158035,2.30575],[-2.041518,2.490467],[-1.910478,2.66393],[-1.76582,2.825356],[-1.608446,2.973961],[-1.439261,3.10896],[-1.259169,3.22957],[-1.069074,3.335006],[-0.869878,3.424485],[-0.662487,3.497224],[-0.447804,3.552437],[-0.226732,3.589341],[-0.000176,3.607153],[0.226511,3.589461],[0.447712,3.552654],[0.66252,3.497516],[0.870027,3.424833],[1.069329,3.33539],[1.259517,3.229973],[1.439687,3.109367],[1.608931,2.974358],[1.766344,2.825731],[1.911018,2.664271],[2.042047,2.490765],[2.158526,2.305998],[2.259547,2.110755],[2.344204,1.905821],[2.411591,1.691983],[2.460801,1.470025],[2.553229,0.627944],[2.588592,0.496739],[2.645238,0.376684],[2.720834,0.269734],[2.81305,0.177844],[2.919553,0.10297],[3.038012,0.047068],[3.166095,0.012093],[3.301471,0],[3.301471,-1]]);
  213. }
  214. module GT2_2mm()
  215. {
  216. linear_extrude(height=pulley_t_ht+2) polygon([[0.747183,-0.5],[0.747183,0],[0.647876,0.037218],[0.598311,0.130528],[0.578556,0.238423],[0.547158,0.343077],[0.504649,0.443762],[0.451556,0.53975],[0.358229,0.636924],[0.2484,0.707276],[0.127259,0.750044],[0,0.76447],[-0.127259,0.750044],[-0.2484,0.707276],[-0.358229,0.636924],[-0.451556,0.53975],[-0.504797,0.443762],[-0.547291,0.343077],[-0.578605,0.238423],[-0.598311,0.130528],[-0.648009,0.037218],[-0.747183,0],[-0.747183,-0.5]]);
  217. }
  218. module GT2_3mm()
  219. {
  220. linear_extrude(height=pulley_t_ht+2) polygon([[-1.155171,-0.5],[-1.155171,0],[-1.065317,0.016448],[-0.989057,0.062001],[-0.93297,0.130969],[-0.90364,0.217664],[-0.863705,0.408181],[-0.800056,0.591388],[-0.713587,0.765004],[-0.60519,0.926747],[-0.469751,1.032548],[-0.320719,1.108119],[-0.162625,1.153462],[0,1.168577],[0.162625,1.153462],[0.320719,1.108119],[0.469751,1.032548],[0.60519,0.926747],[0.713587,0.765004],[0.800056,0.591388],[0.863705,0.408181],[0.90364,0.217664],[0.932921,0.130969],[0.988924,0.062001],[1.065168,0.016448],[1.155171,0],[1.155171,-0.5]]);
  221. }
  222. module GT2_5mm()
  223. {
  224. linear_extrude(height=pulley_t_ht+2) polygon([[-1.975908,-0.75],[-1.975908,0],[-1.797959,0.03212],[-1.646634,0.121224],[-1.534534,0.256431],[-1.474258,0.426861],[-1.446911,0.570808],[-1.411774,0.712722],[-1.368964,0.852287],[-1.318597,0.989189],[-1.260788,1.123115],[-1.195654,1.25375],[-1.12331,1.380781],[-1.043869,1.503892],[-0.935264,1.612278],[-0.817959,1.706414],[-0.693181,1.786237],[-0.562151,1.851687],[-0.426095,1.9027],[-0.286235,1.939214],[-0.143795,1.961168],[0,1.9685],[0.143796,1.961168],[0.286235,1.939214],[0.426095,1.9027],[0.562151,1.851687],[0.693181,1.786237],[0.817959,1.706414],[0.935263,1.612278],[1.043869,1.503892],[1.123207,1.380781],[1.195509,1.25375],[1.26065,1.123115],[1.318507,0.989189],[1.368956,0.852287],[1.411872,0.712722],[1.447132,0.570808],[1.474611,0.426861],[1.534583,0.256431],[1.646678,0.121223],[1.798064,0.03212],[1.975908,0],[1.975908,-0.75]]);
  225. }