The distance between the forms should be measured from the sides of the forms furthest away from the midpoint of the strongback - that's the side that the strips will touch as the are bent toward the stems.

If you measure the gap between forms, the distance will be 11.5" due to the thickness of the form - except between stations 8 & 9 - that will be 11" because you have to account for the thickness of both forms.

It seems to me that the easiest way to do it is to mark the strongback every 12" and then go back and carefully indicate which side of the line the form is positioned on (it should be on the side furthest from the stem, with the alignment marks facing the stem).

Sheesh - that almost sounds like I know what I'm talking about. If that's the case - how come I just aligned a perfect spiral twist into the bow end of my Guillemot L? I got so depressed when I realized that I had done this that I went back to working on the Laundry room for 3 days.

EdP