Sewing Strip Sets
I have read many times that one should sew strips in alternate directions to prevent the strip set from curving.
I have not been able to figure out the "mechancs" of why.
From my experience, I sew the strips in "whatever" direction, and - if the strips were cut straight - my strip set is straight.
I've done most of my sewing on an old Pfaff 1471.
Can/Will someone explain why/how they get curved strip sets if they sew all the seams in the same direction?