On 9/30/2023 6:02 AM, Karl Exler wrote:
what is the preferred way to round edges of standard objects e.g an
cylinder(h=3,r=5) ?
As Revar says, using BOSL2 is the easiest.
If you want to DIY for some reason, the usual rounding techniques
involve positioning round things and then either hulling them or filling
in between them.
Here are two ways to make a rounded cylinder:
module roundcyl_hull(r, h, roundr) {
hull() {
for (z = [roundr, h-roundr]) {
translate([0,0,z]) rotate_extrude()
translate([r-roundr, 0]) circle(r=roundr);
}
}
}
roundcyl_hull(10, 20, 2);
module roundcyl_fill(r, h, roundr) {
for (z = [roundr, h-roundr]) {
translate([0,0,z]) rotate_extrude()
translate([r-roundr, 0]) circle(r=roundr);
}
cylinder(h=h, r=r-roundr);
translate([0,0,roundr]) cylinder(h=h-roundr*2, r=r);
}
translate([20,0,0]) roundcyl_fill(10, 20, 2);
Note that the "fill" variant (on the right) has a slight ridge at the
top and bottom. That's because the circle being extruded has only 7
sides, and doesn't have a vertex pointing up that extends all the way to
the actual radius, while the fill cylinder does extend to the full
height. This can be addressed by forcing the circle to have a multiple
of four sides.
Note also that there are several corner cases that this doesn't attempt
to address. Both will, for instance, get into trouble if the cylinder
radius or height are less than twice the rounding radius.
On 9/30/2023 6:02 AM, Karl Exler wrote:
> what is the preferred way to round edges of standard objects e.g an
> cylinder(h=3,r=5) ?
As Revar says, using BOSL2 is the easiest.
If you want to DIY for some reason, the usual rounding techniques
involve positioning round things and then either hulling them or filling
in between them.
Here are two ways to make a rounded cylinder:
module roundcyl_hull(r, h, roundr) {
hull() {
for (z = [roundr, h-roundr]) {
translate([0,0,z]) rotate_extrude()
translate([r-roundr, 0]) circle(r=roundr);
}
}
}
roundcyl_hull(10, 20, 2);
module roundcyl_fill(r, h, roundr) {
for (z = [roundr, h-roundr]) {
translate([0,0,z]) rotate_extrude()
translate([r-roundr, 0]) circle(r=roundr);
}
cylinder(h=h, r=r-roundr);
translate([0,0,roundr]) cylinder(h=h-roundr*2, r=r);
}
translate([20,0,0]) roundcyl_fill(10, 20, 2);
Note that the "fill" variant (on the right) has a slight ridge at the
top and bottom. That's because the circle being extruded has only 7
sides, and doesn't have a vertex pointing up that extends all the way to
the actual radius, while the fill cylinder does extend to the full
height. This can be addressed by forcing the circle to have a multiple
of four sides.
Note also that there are several corner cases that this doesn't attempt
to address. Both will, for instance, get into trouble if the cylinder
radius or height are less than twice the rounding radius.
