And since I'm using SW and waiting for the wood to arrive I also began to create a 3d assembly. Then I encountered a curious scale issue with the plans that I downloaded from Mr. Anderesen's website.

Thirst thing I did, was to check that the scale ruler placed on each sheet is in effect 6 inches long. All correct. Then I traced the ribs using the Sheet Nº4, and began to assembly the center section of the wing using the sheet Nº5 (which also has a scale ruler and is also 6 inches, all correct). When I placed the first ribs in their correct location over the plan, I noticed that they are indeed longer.

The Rib 1 is 694,30mm on Sheet Nº5 and 704,10mm on Sheet Nº4   

Here is the Rib 1 traced on Sheet Nº4

Here is the Rib 1 layed on sheet Nº5

The servo hardwood bearers appear in a different position but the first spar is coincident with the plan.

Anyway I'm mentioning this because I've seen this issue raised a couple of times here on RCSB in the past. I don't think that it's somehow problematic for the build itself, perhaps some weird problem with the pdf conversion of the web version of the plans. 

Hello Mike, thank you, I'll start a build thread in the appropriate forum