How to cut an object in two halves?

K8200 3D Printer K8200 - Printer software (repetier, slicer, ...) a
1

Hello,

does anybody know how an existing object (*.stl file) can be cut in two halves, so that both halves can be printed with a big flat surface on the heatbed, without any support structures? Then I want to glue the halves together.

Thanks
Michael

2

I don’t know about any automated software to do that. Personally, I use openscad for such tasks. Simply cut away one half and then the other. Of course you will also have to rotate one of the two halves.

~ Tectu

3

[quote=“Fieldmouse”]Hello,

does anybody know how an existing object (*.stl file) can be cut in two halves, so that both halves can be printed with a big flat surface on the heatbed, without any support structures? Then I want to glue the halves together.

Thanks
Michael[/quote]
U can use netfabb. Basic version is FREE.
I don´t know about the Windows Program, but the Mac App is
very easy tp use, it´s nearly self explaining. Within half an hour
and i´ve understood the needed options of this program
It includes rudimental 3D design options eg cut, but no merge.
Also included is to build simple objects.

Greets
seefew

4

Hello,

[quote=“Tectu”]Personally, I use openscad for such tasks. Simply cut away one half and then the other. Of course you will also have to rotate one of the two halves.
[/quote]

How do you import the *.stl file into OpenScad? I did see the export function for *.stl files, but I find no import function. OpenScad seems to accept only *.scad and *.csg files.

Thanks,
Michael

5

I found out how it works with OpenScad, and I did also make two bores in each half, so that it’s easier to glue the two halves exactly together:

bore_distance = 3;
bore_diameter = 0.1;
bore_length = 0.4;
cubesize = 1000;
intersection() {        // cut off lower half
  rotate([0,180,0])     // [0,0,0] or [0,180,0]
  {
    difference()        // make two bores
    {
      import("full_path_and_filename.stl");
      {
        translate([0, bore_distance / 2, 0]) cylinder(h = 2 * bore_length, r = bore_diameter, center = true, $fn = 20);  
        translate([0, -bore_distance / 2, 0]) cylinder(h = 2 * bore_length, r = bore_diameter, center = true, $fn = 20);  
      }
    }
  }
  translate([-cubesize/2,-cubesize/2,0])   // this is the lower half which is cut away
    cube(cubesize);
}
6

I’m glad it works for you. The import() function is the correct way to import your *.stl.

~ Tectu

7

Hi all,

finally I’ve successfully printed the two halves. Which glue do you recommend for PLA?

Thanks,
Michael

8

I’v glue PLA with Cyanolate glue (superglue)
it worked with ABS but not so good (use acetone to melt ABS the make a ‘fusion’ between parts)

9

Found something really cool for gluing pla together. Friction welding. Here’s the instructions on how to do this. It’s a great article and works really well. http://makezine.com/projects/make-34/skill-builder-finishing-and-post-processing-your-3d-printed-objects/