from koko.lib.shapes import * from math import sqrt # One cad unit is 1cm cad.mm_per_unit = 10 # laser kerf is orders of magnitude less than material thickness # shopbot kerf is same order as material thickness, so joint design needs modification # Some parameters are size related. Some of the design is based on how the machinen behaves # TODO # Laser version # 1) Slightly increase size of center pin for better fit # 2) Add bigger chamfer to end of center pin # 3) Make center pin base triangular for extra strength # Shop bot version # 1) Sort out dogs on slots # 2) Increase material thickness # 3) Make slots slightly taller, SB cuts around line so end of tang is currently an 'exact fit', needs some play # 4) increase length of tang to improve machine = 'laser' #machine = 'shopbot' if machine == 'laser': # setup for Epilog Laser and 3mm ply k = 0.17/cad.mm_per_unit # Tool Kerf t = 3.0/cad.mm_per_unit # Material thickness c = 0.2/cad.mm_per_unit # Material Compliance. Estimate of the amount of non-elastic deformation that will occur once on the contact surfaces of the interferance fit #sl = 50/cad.mm_per_unit # Test part length #sh = 20/cad.mm_per_unit # Test part height tang_indent = 3 scale = 53/cad.mm_per_unit # 50 mm major part defining scale hingeslotw = 1.5/cad.mm_per_unit hingesloth = 50/cad.mm_per_unit # rough guide to expected size of slots hingetab = 3/cad.mm_per_unit elif machine == 'shopbot': # setup for shopbot 10mm ply # machine setup on vs around vector is also different k = 6/cad.mm_per_unit # Tool Kerf t = 12/cad.mm_per_unit #11.2/cad.mm_per_unit # Material thickness c = 0.5/cad.mm_per_unit # Material Compliance. Estimate of the amount of non-elastic deformation that will occur once on the contact surfaces of the interferance fit #sl = 150/cad.mm_per_unit # Test part length #sh = 80/cad.mm_per_unit # Test part height tang_indent = 4 scale = 200/cad.mm_per_unit # 50 mm major part defining scale hingeslotw = 7/cad.mm_per_unit # just over kerfs hingesloth = 150/cad.mm_per_unit # rough guide to expected size of slots hingetab = 10/cad.mm_per_unit # Joint size definitions j_ph = t # Pin height. All pins / tangs are same height. if j_ph < (3*k): j_ph = (3*k) # Minimum pin height has to allow for a tool cut down the center j_cpl = t*2 # Center locating pin length beyond edge of material, should be slightly longer than tangs to help ease joint assembly j_tl = t*1.8 # Tang length beyond edge of material j_tl2 = j_cpl*tang_indent # Tang length back into material from edge j_fsh = (j_ph/3)*1.05 #k # Flexure slot height in tang, add a bit to make sure tool fits if j_ph is only 3*k j_fullh = j_ph*6 # Full joint height, should be sum of parts # Joint part A - with the tangs # Origin of joint is half way up join on the boundary edge of the material # Made by adding a chunk of material and then cutting out tangs. # Add rect make it overlap by j_cpl*0.1 with existing material to gaurentee no math error gaps. jointa_add = rectangle(-(j_cpl*0.1), j_cpl, -j_fullh/2, j_fullh/2) # Remove material all around upper half of center locating pin and upper tang jointa_remove = (rectangle(-j_tl2,0, (j_ph*2.5)-(k*0.1),(j_ph*2.5)+(k*1)) # thin free movement cut back into material on upper edge of upper tang. Make slightly bigger than kerf to gaurentee tool fits + rectangle(0,t-c, (j_ph*2.5)-(k*0.1),j_fullh/2) + triangle(t-c,j_ph*2.5, t-c,j_fullh/2, t+c,j_fullh/2) # preasure fit edge slope on upper tang (take off kerf to aid pressure fit). Need to be careful that tool still fits + triangle(j_tl*0.8,j_fullh/2, j_tl,j_fullh/2, j_tl,j_ph*2.0) # chamfer upper side of upper tang + rectangle(j_tl,j_cpl, j_ph/2,j_fullh/2) # remove material beyond end of tang #+ triangle(-(t*1.5),-(t*1.5), -(t*1.8),-(t*1.5), -(t*1.8),-(t*1.8)) # chamfer lower side of upper tang + rectangle(-j_tl2,j_cpl, j_ph*0.5,j_ph*1.5) # remove material between tang and center locating pin + triangle(j_cpl*0.9,j_ph*0.5, j_cpl,j_ph*0.5, j_cpl,j_ph*0.4) # chamfer upper side of center locating pin + rectangle(-j_tl2,j_tl*0.6, j_ph*2-(j_fsh/2), j_ph*2+(j_fsh/2)) # Flexure slot in middle of tang ) # Reflect the above around the line of symetry of the joint jointa_remove = jointa_remove + reflect_y(jointa_remove, 0) # Joint part B - the holes # Must add dogs to the corners of these holes jointb_remove = ( rectangle(-t/2, t/2, j_ph*0.9, j_ph*2.7) + circle(-t/2, (j_ph*0.9)+k/2, k/2) + circle(-t/2, (j_ph*2.7)-k/2, k/2) + circle(t/2, (j_ph*0.9)+k/2, k/2) + circle(t/2, (j_ph*2.7)-k/2, k/2) + rectangle(-t/2, t/2, -(j_ph*0.5), j_ph*0.5) + circle(-t/2, -(j_ph*0.5)+k/2, k/2) + circle(-t/2, (j_ph*0.5)-k/2, k/2) + circle(t/2, -(j_ph*0.5)+k/2, k/2) + circle(t/2, (j_ph*0.5)-k/2, k/2) + rectangle(-t/2, t/2, -j_ph*2.7, -j_ph*0.9) + circle(-t/2, -(j_ph*0.9)-k/2, k/2) + circle(-t/2, -(j_ph*2.7)+k/2, k/2) + circle(t/2, -(j_ph*0.9)-k/2, k/2) + circle(t/2, -(j_ph*2.7)+k/2, k/2) ) # Some wall part size defs ww = scale*2.5 # WallWidth wh = scale # WallHeight cw = ww/10 # CrenelWidth # Make a slot pattern hinge centered on 0,0 def make_hinge(width, height): # calc actual height of slots ht = math.floor(height / hingesloth) print "number of hinge slots", ht ht = (height - ((ht+1)*hingetab))/ht # set start position x = -width/2 y = -(height/2 + ht/2 - hingetab/2) hinge = rectangle(x, x+hingeslotw, y, y+ht) #simple rect to start shape, will get included twice while(x < width/2): # slot pattern a y = -(height/2 + ht/2) while(y < height/2): hinge += rectangle(x, x+hingeslotw, y, y+ht) y += ht+hingetab # slot pattern b x += hingeslotw*2 y = -(height/2 - hingetab) while(y < height/2): hinge += rectangle(x, x+hingeslotw, y, y+ht) y += ht+hingetab x += hingeslotw*2 return hinge # Make a window centered on 0,0 def make_window(width, height): window = rectangle(-width/2, width/2, -height/2, height/2) window += taper_x_y(rectangle(-width/2, width/2, height/2, height), 0, height/2, height, 1, 0.2) return window # Make some stone pattern for side of walls def make_stones(width, height): ws = (width/3) * 0.9 hs = (height/3) * 0.9 stones = rounded_rectangle(-(width/2), -(width/2-ws), -(height/2), -(height/2-hs), ws*0.2) stones += rounded_rectangle(-(width/2), -(width/2-ws), -(hs/2), (hs/2), ws*0.2) stones += rounded_rectangle(-(ws/2), (ws/2), -(hs/2), (hs/2), ws*0.2) stones += rounded_rectangle(-(ws/2), (ws/2), (height/2-hs), (height/2), ws*0.2) stones += rounded_rectangle((width/2-ws), (width/2), -(hs/2), (hs/2), ws*0.2) return stones # Make a piece of wall centered on 0,0 def make_wall_a(width, height, crenelw): # Main body of wall wall = rectangle(-width/2, width/2, -height/2, height/2) # Crenelations x = (-ww/2)+cw while(x < (ww/2)): wall -= rectangle(x, x+cw, (wh/2)-(cw/2), wh/2) x += cw*2 # Add joint parts wall += move(jointa_add, width/2, 0) wall -= move(jointa_remove, width/2, 0) wall += move(reflect_x(jointa_add, 0), -width/2, 0) wall -= move(reflect_x(jointa_remove, 0), -width/2, 0) # Add some decoration wall -= move(make_window(cw/3, cw*2/3), -cw*1.5, cw/2) wall -= move(make_stones(cw*2.5, cw*1.5), cw*1.5, 0) return wall def make_wall_b(width, height, crenelw): # Main body of wall wall = rectangle(-width/2, width/2, -height/2, height/2) # Crenelations x = (-ww/2)+cw while(x < (ww/2)): wall -= rectangle(x, x+cw, (wh/2)-(cw/2), wh/2) x += cw*2 # Add joint parts wall -= move(jointb_remove, (width/2)*0.9, 0) wall -= move(jointb_remove, -(width/2)*0.9, 0) # Add some decoration wall -= move(make_window(cw/3, cw*2/3), -cw, cw/2) wall -= move(make_window(cw/3, cw*2/3), cw, cw/2) return wall # Make a tower section roughly 6 sections wide # width = a single section # origin is not at center but on left hand edge def make_tower(swidth, height, crenelw): twidth = swidth*(4+(3*0.6)+0.25) # Basic rect for body tower = rectangle(0, twidth, -height/2, height/2) # Add some hinges tower -= move(make_hinge(swidth*0.6, height), swidth*1.3, 0) tower -= move(make_hinge(swidth*0.6, height), swidth*2.9, 0) tower -= move(make_hinge(swidth*0.6, height), swidth*4.5, 0) # Add some crenelations x = swidth*0.5 - cw*1.5 while(x< swidth): tower -= rectangle(x, x+cw, (height/2)-(cw/2), height/2) x += cw*2 x = swidth*2.1 - cw*1.5 while(x< (swidth*2.6)): tower -= rectangle(x, x+cw, (height/2)-(cw/2), height/2) x += cw*2 x = swidth*3.7 - cw*1.5 while(x< (swidth*4.2)): tower -= rectangle(x, x+cw, (height/2)-(cw/2), height/2) x += cw*2 x = swidth*5.3 - cw*1.5 while(x< (swidth*5.8)): tower -= rectangle(x, x+cw, (height/2)-(cw/2), height/2) x += cw*2 # Add joints to form this section into a cuboid tower += reflect_x(jointa_add, 0) tower -= reflect_x(jointa_remove, 0) tower -= move(jointb_remove, swidth*(5.8+0.1), 0) # Add some joints for walls tower -= move(jointb_remove, swidth*0.5, -(height/2-wh/2)) tower -= move(jointb_remove, swidth*2.1, -(height/2-wh/2)) tower -= move(jointb_remove, swidth*3.7, -(height/2-wh/2)) tower -= move(jointb_remove, swidth*5.3, -(height/2-wh/2)) # Add some decoration tower -= move(make_window(cw/3, cw*2/3), swidth*0.5, (height/2)-cw*3) tower -= move(make_window(cw/3, cw*2/3), swidth*2.1, (height/2)-cw*3) tower -= move(make_window(cw/3, cw*2/3), swidth*3.7, (height/2)-cw*3) tower -= move(make_window(cw/3, cw*2/3), swidth*5.3, (height/2)-cw*3) return tower parts = ( make_tower(scale, scale*2.5, cw) #move(make_wall_a(ww, wh, cw), 0, 0) #+ move(make_wall_b(ww, wh, cw), ww*1.2, 0) ) cad.shape = parts