On Sunday I finally finished up my Mario block for the Super Mario QAL.
It didn't turn out too wonky or stretched out from not using any stabilizer, so I think I will be able to do the rest of the blocks sans Pellon.
I did come up with a method to use the wash away interfacing with some Lite Steam a Seam tape to hold my blocks down without adding too much stiffness.
That was the start of my Luigi block above, using the Steam a Seam tape. I think this would have worked quite well if only I had drawn my lines correctly!
After trying it out with three rows, I realized my sewn squares were looking pretty tiny. It turns out when I drew my grid on the interfacing, I was making my lines 1/8th in short. I think it had to do with the thickness of my ruler.
Anyone able to properly draw a grid should be able to use this method, and it would be a lot faster than sewing piece by piece.