Curtain rods of all kinds and shapes come ready made in many stores, where you can expect to pay reasonable or sometimes not-so-reasonable prices, depending upon how elaborate a rod you choose. But most shower curtain rods come in standard sizes and configurations designed to fit the most common bathtub and shower shapes -- which may not fit the space you have in mind. If you have this dilemma, take comfort in knowing you can make one yourself inexpensively.
Use a flexible measuring tape to measure the total length -- including the bend -- of the L-shaped area you want your curtain rod to cover and cut a piece of 1-inch schedule 40 polyvinyl chloride pipe to that length. Mark the center point of the bend with a pencil for later reference.
Tape one end of the pipe shut, and put a small funnel in the other end.
Heat ordinary sand in a baking dish in the oven until it is too hot to touch.
Wear insulated gloves or oven mitts to remove the sand from the oven and for the following step.
Transfer the hot sand inside the pipe using a funnel in one end -- to a level just slightly beyond the point where you wish to make a bend. Let it stand until the pipe is hot to the touch and appears softer and more pliable, then lay it upon a flat, level surface.
Bend the pipe slowly at the point where you need your rod to make the L-turn while keeping it against the flat surface so it does not distort in any other direction while bending.
Continue to work it slowly into the correct bend without letting go. You need to hold the shape until the PVC cools sufficiently to become rigid once more, so it retains the bend.
Pour out the sand.
Attach a PVC pipe flange -- furniture grade optional -- to each wall at the height needed for your curtain rod, and insert the pipe ends into the flanges.
Paint the pipe and flanges with plastic paint to finish. This step is optional and meant for regular plumbing pipe. Furniture grade pipe is available in many plastic colors that do not need painting.
Screw a sturdy hook into the ceiling above the curve in the rod and hang a decorative chain long enough to reach the top of the rod from the hook.
Suspend the pipe from the chain using a large S-hook slightly larger than 1-inch diameter on the end of the chain, for added support at the corner bend.