I'm in the 365 day challenge started in Australia...the first blocks are 3" finished. I have been cutting several out and then sewing, so here's a way to keep them and other small blocks all together while piecing.
Instead of using my good rotary cutter, I used the one I have designated for Paper. Cut 8 1/2" squares of a inexpensive flannel backed vinyl tablecloth, leaving the manufactured edge in place. I cut 14 squares...it is quite thick..
Layer the squares in a pile with vinyl side up.
Using clips or binder clips "pin" the squares together on all four sides, keeping the manufactured edges on the same side.
With a slightly longer straight stitch length, sew 1/2" seam, removing clips as you sew ... put the flannel side down next to the feed dogs...I didn't and it slipped about--duh...notice the sloppy seam
Here's how my unsewn blocks look
It's easy to transport blocks to a sit n sew, simply close the book and cinch with a binder clip
I made mine 8 1/2 " thinking it would handle up to 6" block pieces, but it could be made larger--14-15" to accomodate 12" finished blocks.