33 lines
1.3 KiB
OpenSCAD
33 lines
1.3 KiB
OpenSCAD
|
screw_gear(8, 4, 2, 8, 18, 32);
|
||
|
|
|
||
|
|
module screw_gear(outer_radius, inner_radius, thickness, thread_length, precision, total_length)
|
||
|
|
{
|
||
|
|
linear_extrude(height=total_length, twist=360*total_length/thread_length, slices=360)
|
||
|
|
polygon(
|
||
|
|
points = screw_crosssection(outer_radius, inner_radius, thickness, thread_length, precision),
|
||
|
|
paths = [ range((precision+8)*2) ]
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
function screw_crosssection(outer_radius, inner_radius, thickness, thread_length, precision) =
|
||
|
|
concat(
|
||
|
|
[ for (x=[1 : 8]) polar(outer_radius, thickness*360/thread_length*x/8) ],
|
||
|
|
[ for (x=[1 : precision])
|
||
|
|
polar(
|
||
|
|
outer_radius-(outer_radius-inner_radius)*x/precision,
|
||
|
|
thickness*360/thread_length + x/precision*(180-(thickness*360/thread_length))
|
||
|
|
)
|
||
|
|
],
|
||
|
|
[ for (x=[1 : 8]) polar(inner_radius, 180 + thickness*360/thread_length*x/8) ],
|
||
|
|
[ for (x=[1 : precision])
|
||
|
|
polar(
|
||
|
|
inner_radius+(outer_radius-inner_radius)*x/precision,
|
||
|
|
180 + thickness*360/thread_length + x/precision*(180-(thickness*360/thread_length))
|
||
|
|
)
|
||
|
|
]
|
||
|
|
);
|
||
|
|
|
||
|
|
function polar(r,theta) = r*[sin(theta), cos(theta)]; // convert polar to cartesian coordinates
|
||
|
|
|
||
|
|
function range(n) = [ for(x = [0 : n-1]) x ];
|