I hand pieced a wallhanging and had a similar problem of lining up rows of seams, I found pins were a pain in the ....... as I was always stabbing myself or getting the thread tangled. I ended up taking a needle and thread and tying the seam. I put put the needle through one side of the seam I needed to match up, leaving a nice long tail of thread, and then brought it up the other side and just tied a knot with the 2 ends. I did this to all the seams in the row before I started sewing, they all line up beautifully. ( I hope this makes sense
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