I am trying to calculate the necessary trace width for certain traces on my pcb with online calculators.
From googling around I found out that fritzing/aisler produces pcbs with a copper thickness of 35 um which is one variable needed for the calculation. ( I hope the 35 um are correct).
The online calculators always calculate a trace width for internal and external traces.
I think that my traces are external but I am not sure. I am unsure because the traces on the pcbs are enclosed by the surface-finish-layer. Does this surface-finish-layer make all traces internal traces? Probably not, but I am not sure, so hopefully someone of you knows an answer, so I can be sure which calculated trace width is the correct one for me:-)
Btw: My pcb is a one-layer-pcb. So I have the electronic parts going in on the top side and all the traces are located on the bottom side. I am not using any vias or so.