Katybob,
for J-13 I measured all the pieces (except the tear drops) and rotary cut then pieced. I cut out the tear drops from freezer paper. Then I turned the sean allowance over the paper and finger pieced, but it wasn't 'holding' in place as much as I wanted so I hand basted the seam allowance down, the appliqued them.
For J-5 I made the center square block, leaving extra seam allowance. Then made the outer 'frame,' turning the seam allowance under. I think I hand basted that seam allowance (but might have done a little on the machine). Then when I went to applique that top piece onto the bottom piece it kept shifting so much that I machine basted aprroximately 4 stitches on each of the four sides to hold it in place. I find that it holds the pieces in place and if I've used the longest stitch on my machine it doesn't take too long to remove.
Love your blocks!