robertferanec , 04-16-2017, 11:43 AM
It depends on what would you like to achieve. In the rules, you can set up specific track width for specific layer and then during layout select "use track width from rules". However, from my experience this not always work correctly (for some reasons, Altium sometimes switch to Use custom width). PS: I do not know the exact names of the options, I am travelling and can not use Altium to check the names, so it may be called a little bit differently.
What we do, initially we route all the 50OHM signals by same width on same layers (e.g. we use 0.1mm) and by the end of the layout we change all the 0.1mm tracks on each layer to the width we need to meet 50OHM impedance.
I hope this helps.