Stackup information PCBs
Information about the stackup for a four-layer PCB.
I would be nice to have a stackup for every PCB thickness seeedstudio provides. This makes impedance based routing possible.
I agree this would be useful for a low cost rough impedance control, or even for planning the trace widths and spacing when you plan to order impedance control.
I agree this would be useful for a low cost rough impedance control, but as impedance control is a separate service, and for this I assume you will have to document stackup and routing widths/spacing.