Printing Convex Overhangs

[Roxy]

It was interesting to see how faithfully the printer captured the facets of the sphere. The sphere didn't have enough geometry to make it smooth. I want to try to print a golf ball with dimples. That would be a good test.

The code at the bottom has the fineness of the sphere turned up so you will have a better approximation of the sphere. It will take a minute or two to compile.

y95-03.jpg y95-04.jpg

And adding that second sphere(r=20) command will save you a lot of plastic and print time. It will hollow out the sphere which will give you an extra data point. At the start of the print you will be trying to bridge out at almost 90 degrees and you will see how well you can do that on outer perimeters. Once you get up halfway, you will be trying to bridge out on inner perimeters. I have more problems with outer perimeters, but inner perimeters have their own set of issues. And that is why I cut a corner into the sphere. Corners cause me a lot of trouble on both inner and outer perimeters but in different ways. I suspect you are going to see a difference in behavior once you get past the half way mark.

z=83.75; difference() { sphere(r=25, $fn=100);
sphere(r=20);
translate([0,0,-30]) cube([40,40,60]);
translate([-20,-25,-z]) cube([60,60,60]);
}
translate([-25/2,-25/2,-(z-60+1)]) cube([25,25,1.1]);


If you want to see what the changes to the code do, take a look at the attached .STL