SO, I made a little calculation, I post it for reference purpose (who knows, perhaps one day it will help another guy using metric system).
A = 30' = 9.15 ms
B = 18'6" = 5.63 ms
C = 10' = 3.048 ms
Diameter :
largest 4" = 10.16 cms (I believed that was bigger than that!)
smaller 3" = 7.62 cms
In the game scale (supposed to be 28mm or 1/58, according to threads I readed here) :
A = 16 cms
B = 9 cms
C = 5 cms
Diameter :
largest : 0.17 cms (??? I 'll have to make bigger posts than that
)
smaller : 0.13 cms (??? I 'll have to make bigger posts than that
)
thanks again
I found some tubing and stuff to make it, and even a yellow paint wich will do the job
dimitri