Originally Posted by
MadQuilter
When you paper piece, the stitches have to be smaller or the seam will distort/pull apart when you take out the paper. Doing it by hand with paper may not give the pieces enough strength if you use regular paper. Using water soluble materials, it shouldn't matter because you won't be tugging on any seams. I'd say try it. If it works, go for it.
This explains why paper foundations are not the greatest idea. Madquilter - you do give helpful info
I see no reason why fabric (or pellon or used dryer sheets - yes, I know some have a concern about using dryer sheets) would not work for foundation piecing by hand.