origamigoldfish - If you're not already using leaders, there's a chance that using leaders could help prevent your machine from eating the triangle points. I like to use a scrap about 1.5" x .75" for a leader. Sew almost to the edge of the leader, and then (raise the presser foot and) put what you want sew right next to the leader. For step 1 of sewing the two triangles together to make a square, I would rotate the leader to match the 45 degree left edge of the fabric.