Cannot print the following openscad model

[greengecko 8]

Hi,

I would like to print a sail for a sailing boat and developed a openscad script for that. The model does render and I can export it as an stl file. Now the problem start:

regardless which slicer I use (cura, kisslicer) the resulting gcode file contains errors (e.g. kisslicer adds some funny bits at the edges of the sail) and cura does a weird thing and displaces the layer during mid print for about a cm (the gcode looks fine though).

Could someone tell me how to clean this file?

Here is the openscad code (I commented out some of the parts to be able to print just one sail)

and I attach also the resulting stl file.

I have the suspicion that the difference between two spheres does result in some funny misoriented triangles. But even netfabb does not find an error and hence the routine does not repair it. A hint how to clean the model (stl) file would be great.

link to stl file http://www.bvwk69.de/sail.stl

Thanks in advance.

$fn=200;

rotate([-90,0,0])difference()

{

union()

{

//

//difference()

//{

//translate([0,1,82]) scale([5,0.5,0.8]) sphere(13);

//union()

//{

//translate([0,3,82]) scale([5,0.5,0.8]) sphere(11);

//translate([90,0,50])cube([150,40,100],center=true);

//translate([-90,0,50])cube([150,40,100],center=true);

//

//}

//}

difference()

{

translate([0,1,40]) scale([3,0.5,1]) sphere(31);

union()

{

translate([0,3,40]) scale([3,0.5,1]) sphere(29);

translate([110,0,50])cube([150,40,100],center=true);

translate([-110,0,50])cube([150,40,100],center=true);

}

}

}

union(){

translate([-50,2.7,0])color("Red")cube([100,20,200]);

cylinder(100,2.9,2.9);

}

}

[greengecko 8]

I solved the layer shift problem. It had to do with too tight belts and and too loose pulleys.

As always if two problems happen at once we tend to think about only a single cause.

So in this case it is a win to cura, which slices fine and kisslicer creates some funny artifacts. Still I have no idea how to repair an visually fine stl file. Meshlab is far too complicated to do this and netfab would just not find anything to repair. Is there another software for repairing models?