he wants to print it in one piece.. so it will prevent overhang and needs of support

ah I see... btw I think "he" is a she....

Jesse,

Nice work so far. I started work on another parametric spool hub yesterday. I included my script. Feel free to use all, some or none of it. Forgive the mess, I kinda threw it together quickly without thinking of others reading it.

A couple features that I was shooting for:

Entirely printable (including center hub)
Interlocking connection in center of hub
Ability to change inside and out side of hub seperately
Tapper ability for both inside and outside of hub
low amount of plastic used
filament holes to hold during spooling then to tie loose end

This looks good.  I think I might grab this and tinker wit it sometime.  What about making the joins symmetrical so that the 2 halves are actually identical?  That way if something breaks, etc you can interchange.

Nice work so far. I started work on another parametric spool hub yesterday. I included my script. Feel free to use all, some or none of it. Forgive the mess, I kinda threw it together quickly without thinking of others reading it.

A couple features that I was shooting for:

Entirely printable (including center hub)
Interlocking connection in center of hub
Ability to change inside and out side of hub seperately
Tapper ability for both inside and outside of hub
low amount of plastic used
filament holes to hold during spooling then to tie loose end

I know you would like them to be one piece, but maybe you can use something here?

Here's a prototype, scaled to approximately the size of a cupcake. 

PLA at 0.4 mm layers and 33% infill.

There's plenty of room to remove material.  I haven't started with that yet.

OpenSCAD code

difference(){
    cylinder(r1=10,r2=5,h=5,$fn=50);
    cylinder(r=2,h=10,$fn=50);
}

translate([0,0,10])
difference(){
    cylinder(r1=5,r2=10,h=5,$fn=50);
    cylinder(r=2,h=10,$fn=50);
}


translate([0,0,3])
difference(){
    cylinder(r=5,h=10,$fn=50);
    cylinder(r=2,h=10,$fn=50);
}

The angles are nearly 30, 60, 90.