module base(width, height, screw){
    difference(){
     square([width, height]);
     side_width = height/6;
     translate([side_width/2,side_width/2]) square([width-side_width, height-side_width]);}
   //translate([0,0,-1]) square([width+.75, width/2 + delta]);
   //translate([width+ ,width/2, -2]) 
   //cylinder(4, d=screw, $fn=50); 
}

module moving(width, height,delta, screw){
    short_side = width/2 + delta;
    difference(){   
        square([width+delta/2, short_side]);
        translate([width+delta/4, short_side/2]) circle(d=screw, $fn=50);} 
}

module long_side(width, height){
    %polygon([[0,0], [width,0], [width,width]]);
    polygon([[0, 0], [width, 0], [2*width, width],[1.5*width, width]]);
}
//Millimeters by default
//  multiple by 25.4;
scale = 25.4*3.77;;
screw_diam = 1/8;
diam = scale* screw_diam;
delta = scale*1.5;
* base(scale*6,scale*12);
long_side(width, height);
* moving(scale*6,scale*12,delta,diam);