I bought a LARGE sketch pad years ago. Used it up and was going to throw away the 2'x3' hard cardboard it was backed with.
I CUT IT TO THE DIMENSIONS OF MY TOOLING BLOCK.
I covered one side with clear shelf liner and left the other side bare. Keep it next to my bench with the poundo board and a few cutting boards.
The covered side is great to glue on as I use the gum rubber to clean off excess. The other side is my dyeing side.
I have dyed hundreds of pieces on it. Doesn't bleed, barely absorbs, but I've never had rub off onto a new project.
With all of the dye spills it has never gotten soft .
Also, I bought a green cutting mat that sewers use for patterns. I cut it also to my block dimensions. I hate a surface that hangs over my block or is too small when I'm working.
I was left with 2 scraps about 5"x12". These I keep in my drawer and pull them out when I want a quick surface to cut on.
I use these A LOT as I cut many small pieces making wallets, card cases etc and don't need a big cutting surface.
Hope this helps someone