Accurate Strong Gantry

[vargai]

It may well be cheaper and better from a production point of view to build 2 specific machines. Good luck

IMO you will be much better building a router that will cut everything in it's capabiltys, Ie woods,plastics etc to a high standard.
Then buy a milling machine at later date that will do and give the same high accurecy and repeatabilty with Aluminium and Steel etc.

Sorry for late answering. I could have placed this post to a general thread since by going through my one the searching on the good design led the doubt about the primary aim.
Reading the posts after my latest design I recognized or at least felt the generally weak points. Sorry for seeming stubborn. It is not meant to happen. My tenacity is all about my goals and not the way and method to reach it. It is not easy to abandon a main intent and to say right away yes, or no.
So thank you all who involved for your efforts and advice in highlighting my weakness.
I hope I do not have to turn my back on metal and will be able to build a good router for Al and other softer material.