GL wrote: ...now let's compare official widths of 3 boards of different manufacturers...
...so what happens - officially SB F160 is with smallest width. But according your calculations it became widest. No rounding errors can explain this...
thank you for your meticolous but constructive remarks.
About 160 tail question you refer, from Starboard 2006 web page ( http://2006.star-board.com/products/formula.asp
), at O.F.O. lenght it measures 77.9 cm while in my calculation it measures 78.5 cm: only 0.6 cm of difference but really inside of tollerance error of 1-2 cm described above.
Yes, I make drawings from pictures taken from manufactures web sites; I perfectly know this is not surely "the best way" to measure something, but I draw over original pictures using Autodesk Autocad, taking care to bring horizontal and vertical linear dimensions to declared values using images as "way points" in tracing process and correcting possible imperfections and distorsions as much as possible: final images are produced in vector Autocad DWG format and every boards may be easily measured (and compared) with Autocad "Dimension Function" (for those familiar with CAD software)
Anyway this process, as described, produces a "non trascurable" error (technically speaking: a tracing error) plus errors of perspective internal of photo itself (i.e. when camera is not placed perfectly in front of board).
But, as example of how I have worked, look at following image (new FX100-V) where I've traced (in red color) board deck profile over original picture (grey image) and where consequent variances are highlighted:
As you can see, tracing errors are comprised in about 1 cm (thin dark area in right side of the board is a "shadow effect" made by F2 web graphic designers); so, all things considered, I think that even some (good) web images could give us some useful metric information about this (and other) Formula boards.