Mark, that staircase is 8' in Diameter... I think I built that in 2010. The largest 2 panels are 4' x 5.5' and it was difficult for me... the first 6 or 7 steps not so bad ...the next 18 or 19 ~~~*Really Tough*~~~!!!!
Here's an update. I'm waiting for some parts to finish the bench work... but, it's ready for track now!!!