What is traditionally used as the the waistband canvas? From cutter and tailor forum i found people recommend petersham, haircloth and buckram. Could anyone give a more in depth answer?
@martinkuester71 has a post showing what he has done here: https://www.handcrafttailor.com/forum/general-discussions/trouser-fitting
This uses straight cut and bias, not sure how it turned out though!