Once in a while I have to build props that accompany a sign or display. This time I was asked to replicate a simple white column using foam core board. Over the years I have learned to manipulate this material in a number of ways. This project is mostly about scoring and bending.
This small picture was my reference and inspiration. It's actually a picture of the bottom of a row of roman columns... I turned it upside-down. I couldn't find an example of a simple box capital (top of the column). This did the job.
I started by taking a 4'x8' sheet of foam core board and cutting it down to 4'x6-1/2'. Next, I scored the length of the sheet, every 2"... because I want it to bend in on itself. I know from past experience that the cut isn't going to be enough to make the foam core bend like I want, so I ran a dull No. 2 pencil tip through the cuts. This widened each cut and pressed down the foam enough to get the bend I wanted.
Here is the scored sheet laying flat and a circle attached at one corner with clear package tape. I attached the other circle on the opposite side of the sheet. Then I rolled the circles along the edges of the sheet, taping them to the sheet every 2" as I went. I did this by alternating sides every 6 inches or so.
Once I was close enough to tell where the seam would be, I trimmed off the rest of the scored sheet.
Then I just had to tape the seam. The next step was to build a shallow box and tape it on the top of the column. Finally, I cut a couple of long strips of foam core board (one 2" strip and one 1-1/4" strip), scored them and taped them on the column, up under the box. This created the step trim. Done!