Collage and primer?? Do you even use primer for your collage substrates? I didn’t initially, because I used to work mainly on cardboards. But it always bothered me that cardboards welled under water based glue. So I started to look into the matter and it grew into quite a bit of a research. There are so many different ways to prepare a collage substrate. Is it leaving a smooth surface? Does it show through thinner papers? And which brands to use? Especially here in Europe where I am based.