This is a picture I posted in my last blog post. It is from the Jewish Quarter in Prague.
Here is the progression of drawings to final pattern. I decided to create some kind of interesting flower. Here is the design I started with based on the circles from above. I didn't think I wanted four curls on the outside because once I added the third one it looked funny. I did the circle work in Adobe Illustrator because it makes drawing circles so much easier. I don't like drawing irregular curves in Illustrator however because I'm not proficient enough at it. Someday I would love to take a class on Illustrator, but it probably won't be any day soon.
Next I used the window (you could use a light box) to trace the other side.
Then I tried adding a third curl again. It looks okay, but I wasn't sold on it. I decided to try something else. I wore out a whole pencil eraser in this process!
Next I decided that maybe I needed to add a curl going to the bottom of the circle to make it look like the base of the flower.
Then I decided to try adding another layer to the upper curl. I didn't like this one at all. It seemed to skinny and didn't really work.
Next I got frustrated with adding a line to the upper curl so I decided to try playing with the space between the upper two curls. I added a peak which is common on applique flowers. I tried a curved shape, but this pointed one worked better.
Then I decided that the upper curl really did need another piece. I went with a thicker piece to match the line I added to the bottom curl. I redrew this line half a dozen times until I was satisfied with it's thickness.
Finally, I used the window again to trace the right side so the flower was symmetrical. I am very happy with the final result. It was definitely inspired by original ironwork picture, but has been manipulated a ton and I feel like it's now my own design.