Thanks Jammer, the plumbing work is less simple than it seems, it's true.
For the more tight turns in fact i have choosen to use the copper tube than the brass one. Moreover i have used some little brass wheels built by lathe with the same radius of the bend on the external and the radius of the tube in section; this is to prevent the buckling of the tube.
The problem on this kind of model is that we have to use tubes of bigger dimensions than the real machine and is very hard to find the way they have to pass through...
