I started by washng them in my machine and drying them in the dryer. If they were going to go bad, that was the time to see it! They did fine. I undid the stitches holding the tie in the 'tie position'. I used a dresden plate ruler and extended it to the length I needed. I placed the straight edge of the ruler at the point where the tie began to come to a point. I did not take out the stitches at the pointed end of the tie.
I wish I had used iron-on stabilizer on the tie pieces before I sewed them toghether. It would have made it more stable, and I could have done some decorative stitches in the seams between the ties. As it is, I washed the quilt once I was done, but I will recommend that she dry clean it as I am not sure the seams between the ties will take much washing.
I just did one block. It is about 45 by 45 square. It takes twenty ties with what if guess is the regular dresden plate angles.