![](https://www.openscad.info/wp-content/uploads/2020/06/Selection_970-1024x499.png)
This simple Tutorial will walk you through the process of making a cylindrical pipe.
In this Tutorial you will only need two commands:
- cylinder();
- difference();
Bebgin by creating a new model in OpenSCAD then add your first cylinder. We will make the cylinder with a Radius of 10 and a Height of 100. The cylinder will not be centered.
cylinder( r=10,h=100);
Press F5 to Render the Preview. The Press the Reset View Icon and the Magnify Icon to fully reset and center your view.
![](https://i1.wp.com/www.openscad.info/wp-content/uploads/2020/06/Untitled.scad-—-OpenSCAD_971.png?fit=900%2C468&ssl=1)
Add the second cylinder, which will be subtracted later:
cylinder(r=10,h=100); cylinder(r=9,h=100);
Press F5, it seems like nothing happened, but the cylinder was added.
![](https://i2.wp.com/www.openscad.info/wp-content/uploads/2020/06/Untitled.scad-—-OpenSCAD_972.png?fit=900%2C468&ssl=1)
Place a # in front of the first cylinder and press f5, you will see the second cylinder inside the first.
#cylinder (r=10,h=100); cylinder (r=9,h=100);
![](https://i1.wp.com/www.openscad.info/wp-content/uploads/2020/06/Untitled.scad-—-OpenSCAD_973.png?fit=900%2C468&ssl=1)
Remove the # and add the difference command in front of the two cylinders. Place a Left Curly Bracket after the difference() and after the second cylinder.
difference(){ cylinder (r=10,h=100); cylinder (r=9,h=100); }
![](https://i2.wp.com/www.openscad.info/wp-content/uploads/2020/06/Untitled.scad-—-OpenSCAD_974.png?fit=900%2C468&ssl=1)
The opening will look like it is partially closed off, however in the final render it will be open. Press f6 to get a final render.
![](https://i0.wp.com/www.openscad.info/wp-content/uploads/2020/06/Selection_970.png?fit=900%2C439&ssl=1)