Thingiverse link: http://www.thingiverse.com/thing:208591

Settings: MakerWare .3mm/low in two batches (to get the two colors).

Technical notes: We used the following settings in the Thingiverse Customizer, which makes a sturdy, compact model that can be difficult to put together but stays together well even when tossed around.

Sides = 3 and 6Technical notes, OpenSCAD flavor: This is one of my first OpenSCAD designs so it is kind of a hack, but here is the code I wrote to make the Poly-Snap tiles:

Snaps = 3

Side Length = 25

Thickness = 3.5

Border = 3.5

Clearance = .17

Lengthen = .3

// mathgrrl polysnap tiles

////////////////////////////////////////////////////////////////

// PARAMETERS //////////////////////////////////////////////////

/* [Shape] */

// Choose the number of sides for the tile

sides = 5; // [3,4,5,6,7,8,9,10,11,12]

// Choose the number of snaps on each side

snaps = 3; // [2,3,4,5,6,7,8]

/* [Size] */

// Set the length of each side, in mm

side_length = 25;

// Set the thickness of the tile, in mm

thickness = 3.5;

// Set the border thickness, in mm

border = 3.5;

/* [Adjust Fit] */

// Add extra space between snaps, in mm

clearance = .17;

// Add extra length to the snaps, in mm

lengthen = .3;

//radius depends on side length

radius = side_length/(2*sin(180/sides));

//inside radius depends on the border thickness

inside = radius-border/(cos(180/sides));

//width of each snap depends on number of snaps

snapwidth = radius*sin(180/sides)/snaps;

////////////////////////////////////////////////////////////////

// RENDERS /////////////////////////////////////////////////////

union(){

//make the polygon base

poly_maker();

//make the snaps

snap_maker();

}

////////////////////////////////////////////////////////////////

// MODULES /////////////////////////////////////////////////////

//build the polygon shape of the tile

//shape is made up of n=sides wedges that are rotated around

module poly_maker(){

//subtract the smaller polygon from the larger polygon

difference(){

//extrude to thicken the polygon

linear_extrude(height=thickness,center=true){

//rotate the wedge n=sides times at angle of 360/n each time

for(i=[0:sides]){

//rotation is around the z-axis [0,0,1]

rotate(i*360/sides,[0,0,1])

//make triangular wedge with angle based on number of sides

polygon(

//the three vertices of the triangle

points = [[0-.1,0-.1], //tweaks fix CGAL errors

[radius,0-.01],

[radius*cos(360/sides)-.01,radius*sin(360/sides)+.01]],

//the order to connect the three vertices above

paths = [[0,1,2]]

);

}

}

//extrude to thicken the center polygon that will be the hole

linear_extrude(height=thickness+2,center=true){

//rotate the wedge n=sides times at angle of 360/n each time

for(i=[0:sides]){

//rotation is around the z-axis [0,0,1]

rotate(i*360/sides,[0,0,1])

//make triangular wedge with angle based on number of sides

polygon(

//the three vertices of the triangle

points = [[0-.2,0-.2], //tweaks fix CGAL errors

[inside,0-.01],

[inside*cos(360/sides)-.01,inside*sin(360/sides)+.01]],

//the order to connect the three vertices above

paths = [[0,1,2]]

);

}

}

}

}

//build the snaps around the tile

//try the commands alone with i=1 and i=2 to see how this works

//remember to read from the bottom to the top to make sense of this

module snap_maker(){

//rotate the side of snaps n=sides times at angle of 360/n each time

for(i=[0:sides]){

//rotation is around the z-axis [0,0,1]

rotate(i*360/sides,[0,0,1])

//build snaps for first side at the origin and move into positions

for(i=[0:snaps-1]){

//read the rest of the commands from bottom to top

//translate the snap to the first side

translate([radius,0,-thickness/2])

//rotate the snap to correct angle for first side

rotate(180/sides)

//for i^th snap translate 2*i snapwidths over from origin

translate([0,2*i*snapwidth,0])

//rounded box for snap made from a box and cylinder

union(){

//cube part of snap shape at the origin

cube([thickness/2+lengthen,snapwidth-clearance,thickness]);

//post at back of snap to avoid loose teeth

//shifted a bit right to avoid overhangs when sides=3

translate([-.5,.5,0])

cube([thickness/2,snapwidth-clearance-.5,thickness]);

//round part of snap shape at the origin

//move cylinder to the end of the box

translate([thickness/2+lengthen,

snapwidth-clearance,

thickness/2])

//rotate cylinder to match box orientation

rotate(90,[0,1,0])

rotate(90,[1,0,0])

//cylinder of the correct size to match box

cylinder(

r=thickness/2,

h=snapwidth-clearance,

$fn=16 //number of sides

);

}

}

}

}

Update: These Poly-Snap triangle tiles were used by owens on Thingiverse to make a beautiful model of a toroidal polyhedron. So cool!

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