I am writing today because I am working on a new project with a flex-rigid pcb.

I have not a big experience working with that type of pcbs and I started reading about Flex Circuit Technology.

I read that is important that the pad extends under the coverlayer.For that reason, the recommendation from that author is to make the pad 250um-375um larger. 

I attached a photo about I mean.

I suppose that I will have to modify my footprints but 0.25-0.375mm is a nice length?

In order to work with THT pads is the same recomendation.

Did anyone have any experience with flex materials?

Thanks to all.

david