In this Illustrator CS4 tutorial we’ll create a spiral staircase graphic.

This is a fun twisty shape so grab your pen tool and we’ll start with the stringer stair graphic which is the one in the middle shown above.

It all starts by making the shape on the right. To do that we’re going to make the path below that shape. So to start let’s turn on our grid by going into View/Show Grid and then go back and select View/Snap to Grid.

This will make it easier to make this path with precision. Click with the pen tool to make and anchor point then drag a handle down 10 small squares. Move over to the left and down (left 2 and down 2) 2 big squares and click and drag another anchor point but drag up 10 small squares.

The thickness of your stringer is really up to you. I used 4 small squares. So with our selection tool selected (v), hold option (mac) - (alt for windows) and click and drag the path down 5 small squares. This will duplicate the path. Then with your direct selection tool (a), select the two left anchor points and press command j (mac) - (control on windows) on the keyboard to join the anchor points. This should create a line connecting the two paths. Do this for the right side as well.

Next copy and paste in back. Select the two left anchor points and move to the right one small square. Then select the two right anchor points and move left one small square. i filled mine with light grey so you can see how it should look.

Ok next we’re going to want to select both of these shapes and click the divide button in the pathfinder panel. This will intersect the paths as shown. Now select all these shapes and copy them and paste in back. Move down a bit and click Object/Transform/Reflect (vertical axis). Next we want to go to the top group and select the shapes that make up the outside of the stringer (filled black) and click the unite button on the pathfinder panel. There are three shapes we need to select. The main black center, and the two outer black shapes. Double click the shape to enter isolation mode and shift click the three shapes to select them. Click unite and we’re almost there. Then we need to do the same thing for the bottom shape with one exception. Select the main black center shape and the two outer grey shapes, unite, then fill with grey again. You should have something that looks like the shape on the right.

Now we need to do a little dirty work. Go into the lower stair layer and move the bottom left anchor point of the right outer black shape to the right-bottom anchor point of the center grey shape with the direct selection tool. Then use the convert anchor point tool to square off the corners by removing the handles. Repeat this process for the top stair section with a slightly different process by moving the handles to fill the arch of the center black shape. If you need to cheat by making the arch go slightly behind the black shape then coping and and subtracting go right ahead.

Now we need to move the left black shape from the bottom group into the top group. Select the left grey shape in the top group and the left black shape in the top group and click the unite button on the pathfinder panel. Get your remove anchor point tool and click to remove the anchor point that creates the hole in the shape.

We have one thing left to do. Go into the lower group and copy the right black shape. Get out of the group and paste in front. Fill with a lighter grey. Draw a rectangle over the area that represents the front piece. Select that rectangle and the copied right black shape and press command (mac) - (control windows) 7 and make a clipping mask. And that’s it. Now you can just add your gradients and center bar (rectangle with a gradient fill) and you’re done. Watch the video tutorial below for more help.

I hope you enjoyed making a nice stair graphic. Use this to try and make the graphic representing the treads. Good luck.