• プラレールは半径何cｍの急カーブまで曲がれるのか？3Dプリンタしたレールを使いチェック /usePocket.com別館

• (1)レール内側の壁の高さを8mm→3mmに減らし車輪がひっかかるのを防ぐ
• (2)レール外側の壁の高さを8mm→12mmに増やし脱輪防止
• (3)他のレールと連結する部分の壁は8mm→6mmに減らす
• (4)レール幅を38mm→42mmに広げる

• (5)他のレールと連結する凸部分がハメにくいと思っていたら、本物のプラレールにあるフレキシブルさを高めるための溝を入れ忘れていたので、追加。

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$fn=10;

pitch=1/72;
wall_body=12; // normal=8
innerwall_body=3; //normal=8
wall=6; //normal=8
width=42; //normal=38

//main /////////////////////////////////////////////
for (t=[0:pitch:1-pitch]){
    body(t2xy(t),t2xy(t+pitch),t2xy(t+pitch*2));
    }
in(t2xy(1),t2xy(1+pitch));
out(t2xy(0),t2xy(0+pitch));

////////////////////////////////////////////////////
function t2xy(temp)=[50*sin(temp*300),50*cos(temp*300)];

function XY(angle,Ddis,Vdis)=[
sign(Ddis*angle[0])*sqrt(pow(Ddis,2)/(1+pow(angle[1]/angle[0],2)))+sign(Vdis*-angle[1])*sqrt(pow(Vdis,2)/(1+pow(angle[0]/angle[1],2))),
sign(Ddis)*angle[1]/abs(angle[0])*sqrt(pow(Ddis,2)/(1+pow(angle[1]/angle[0],2)))+sign(Vdis)*angle[0]/abs(angle[1])*sqrt(pow(Vdis,2)/(1+pow(angle[0]/angle[1],2)))];

// body
module body(pos1,pos2,pos3){
    Dir1=pos2-pos1;
    Dir2=pos3-pos2;
    linear_extrude(height = 1.5,center=true){
        polygon(points=[pos1+XY(Dir1,0,width/2),pos1+XY(Dir1,0,-width/2),pos2+XY(Dir2,0,-width/2),pos2+XY(Dir2,0,width/2)]);
        }
    linear_extrude(height = wall_body,center=true){
        polygon(points=[pos1+XY(Dir1,0,width/2),pos1+XY(Dir1,0,width/2-1.5),pos2+XY(Dir2,0,width/2-1.5),pos2+XY(Dir2,0,width/2)]);
        polygon(points=[pos1+XY(Dir1,0,-width/2),pos1+XY(Dir1,0,-width/2+1.5),pos2+XY(Dir2,0,-width/2+1.5),pos2+XY(Dir2,0,-width/2)]);
        }
    linear_extrude(height = innerwall_body,center=true){
        polygon(points=[pos1+XY(Dir1,0,9.5),pos1+XY(Dir1,0,8),pos2+XY(Dir2,0,8),pos2+XY(Dir2,0,9.5)]);
        polygon(points=[pos1+XY(Dir1,0,-9.5),pos1+XY(Dir1,0,-8),pos2+XY(Dir2,0,-8),pos2+XY(Dir2,0,-9.5)]);
        }
}

module out (pos1,pos2){
//start out
    Dir=pos2-pos1;
//hiraban
    translate([pos1[0],pos1[1],0]){
    linear_extrude(height = 1.5,center=true){
    polygon(points=[XY(Dir,0,-3),XY(Dir,-7.5,-5),XY(Dir,-7.5,-1),XY(Dir,-3,-1),XY(Dir,-3,1),XY(Dir,-7.5,1),XY(Dir,-7.5,5),XY(Dir,0,3)]);
    }
    linear_extrude(height = wall,center=true){
    polygon(points=[XY(Dir,0,3),XY(Dir,1.5,3),XY(Dir,1.5,8),XY(Dir,0,8),XY(Dir,0,4.5),XY(Dir,-9,6.5),XY(Dir,-9,1),XY(Dir,-7.5,1),XY(Dir,-7.5,5)]);
    polygon(points=[XY(Dir,0,-3),XY(Dir,1.5,-3),XY(Dir,1.5,-8),XY(Dir,0,-8),XY(Dir,0,-4.5),XY(Dir,-9,-6.5),XY(Dir,-9,-1),XY(Dir,-7.5,-1),XY(Dir,-7.5,-5)]);
    }}
}

module in (pos1,pos2){
//start in
    Dir=pos2-pos1;

    translate([pos1[0],pos1[1],0]){
     linear_extrude(height = wall,center=true){
        polygon(points=[XY(Dir,0,-8),XY(Dir,9,-4.5),XY(Dir,9,-9.5),XY(Dir,-1.5,-9.5),XY(Dir,-1.5,9.5),XY(Dir,9,9.5),XY(Dir,9,4.5),XY(Dir,0,8)]);
        polygon(points=[XY(Dir,9,width/2-1.5),XY(Dir,9,width/2),XY(Dir,0,width/2),XY(Dir,0,width/2-1.5)]);
        polygon(points=[XY(Dir,9,-width/2+1.5),XY(Dir,9,-width/2),XY(Dir,0,-width/2),XY(Dir,0,-width/2+1.5)]);
            }
     linear_extrude(height = 1.5,center=true){
        polygon(points=[XY(Dir,0,11),XY(Dir,9,11),XY(Dir,9,width/2-1.5),XY(Dir,0,width/2-1.5)]);
        polygon(points=[XY(Dir,0,-11),XY(Dir,9,-11),XY(Dir,9,-width/2+1.5),XY(Dir,0,-width/2+1.5)]);
     }
     }
 }
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• 作りたい形を指定するだけでプラレールのレールの3Dプリントデータを作成するOpenSCADスクリプト /usePocket.com別館 1 users