I thought I was cutting the pieces bigger than they needed to be, which seems to help with paper piecing. I guess I needed to make them even bigger than that. My seam allowances were getting pretty skimpy, so I ended up cutting some new triangles midway through this block.
It was when I dug into the scrap basket to find more fabric that I realized the blue was the same that I used in block 13. They came from entirely different sources, and I didn't think about them being the same, but sure enough I had some in my stash and some in the leftover Dear Jane bits. I'm trying to to repeat fabrics and it seemed easier to replace the two squares from block 13 than redo all the paper piecing in this block.
I'm all out of the super nifty dissolvo paper, so I went out and got some tracing paper. It isn't nearly as nice, being slippery against the fabric and getting caught in the printer. I went online to find more of the paper and found some in magic shops of all places. It may be easier to go to the fabric store for some more of the fundation paper.