Medieval Carpenter?

[juergenw]

I was looking at the man (bottom left) in You are not allowed to view links. Register or Login to view. and was puzzled by the detail (hidden underneath the green colour) on what the man is leaning on. I thought of a wooden beam and didn't find a real full equivalent in any manuscript. I found some images that I vaguely associate with the details (see attachment).
What do people think? Is medieval carpentry completely wrong and/or do I miss something obvious?
Thanks for any comments in advance.