$fn=100;
dis=35;
hei=20;
scr1=0;
scr2=0;

module base_holder() {
    union() {
        difference() {
            union(){
                hull() {
                    translate([-4,-4,-0])cube([1,8,5]);
                    translate([12.5-13-19.8,-7.5,-0])cube([0.0001,15,5]);
                }
                translate([0,0,0])scale([3.3,2.75,0.5])cylinder(d=12,h=10);
            }
            translate([7,-18,-1])cube([15,36,10]);
            translate([0,0,-1])scale([3.3,2.75,0.5])cylinder(d=10,h=14);
        }
        translate([7,13.93,0])cylinder(h=5,d=2.95);
        translate([7,-13.93,0])cylinder(h=5,d=2.95);
    }
}

union() {
    for (i=[0:3]) {
        translate([0,dis*i,0]) base_holder();
    };
    translate([-.5,0,0]) difference() {
        translate([-23,-7.5,0])cube([3.5,dis*3+15,5]) ;
        translate([-23.5,dis*0.5,2.5])rotate([0,90,0])cylinder(h=10,d=scr1);
        translate([-20.4,dis*0.5,2.5])rotate([0,90,0])cylinder(h=1,d1=4,d2=scr2);
        translate([-23.5,dis*2.5,2.5])rotate([0,90,0])cylinder(h=4,d=scr1);
        translate([-20.4,dis*2.5,2.5])rotate([0,90,0])cylinder(h=1,d1=4,d2=scr2);
    }
};
//p2
union() {
translate([-0.5,0,hei]) union() {
    translate([0,0,0]) difference() {
    union(){
        hull() {
            translate([-4,-4,-0])cube([1,8,5]);
            translate([12.5-13-19.8,-7.5,-0])cube([0.0001,15,5]);
        }
        translate([0,0,0])cylinder(h=5,d=10);
    }
    
    hull() {
        translate([0,0,-1])cylinder(h=7,d=8);
        translate([1,0,-1])cylinder(h=7,d=7.5);
    }
    translate([2,-18,-1])cube([15,36,10]);
};
        translate([0,dis,0]) difference() {
    union(){
        hull() {
            translate([-4,-4,-0])cube([1,8,5]);
            translate([12.5-13-19.8,-7.5,-0])cube([0.0001,15,5]);
        }
        translate([0,0,0])cylinder(h=5,d=10);
    }
    
    hull() {
        translate([0,0,-1])cylinder(h=7,d=8);
        translate([1,0,-1])cylinder(h=7,d=7.5);
    }
    translate([2,-18,-1])cube([15,36,10]);
};
            translate([0,dis*2,0]) difference() {
    union(){
        hull() {
            translate([-4,-4,-0])cube([1,8,5]);
            translate([12.5-13-19.8,-7.5,-0])cube([0.0001,15,5]);
        }
        translate([0,0,0])cylinder(h=5,d=10);
    }
    
    hull() {
        translate([0,0,-1])cylinder(h=7,d=8);
        translate([1,0,-1])cylinder(h=7,d=7.5);
    }
    translate([2,-18,-1])cube([15,36,10]);
};
                translate([0,dis*3,0]) difference() {
    union(){
        hull() {
            translate([-4,-4,-0])cube([1,8,5]);
            translate([12.5-13-19.8,-7.5,-0])cube([0.0001,15,5]);
        }
        translate([0,0,0])cylinder(h=5,d=10);
    }
    
    hull() {
        translate([0,0,-1])cylinder(h=7,d=8);
        translate([1,0,-1])cylinder(h=7,d=7.5);
    }
    translate([2,-18,-1])cube([15,36,10]);
};
                    difference() {
    translate([-23,-7.5,0])cube([3,dis*3+15,5]) ;
    translate([-23.5,dis*0.5,2.5])rotate([0,90,0])cylinder(h=10,d=scr1);
        translate([-20.9,dis*0.5,2.5])rotate([0,90,0])cylinder(h=1,d1=4,d2=scr2);
    translate([-23.5,dis*2.5,2.5])rotate([0,90,0])cylinder(h=4,d=scr1);
    translate([-20.9,dis*2.5,2.5])rotate([0,90,0])cylinder(h=1,d1=scr1,d2=scr2);
};
    };
};