Are you using an internal or external strongback?
If external did you start at the back end and finish with the front? If that is the case you will have trouble as the bow is higher than the stern, so upside down needs more space under it than the stern.
JohnK

: Ive just started to put together the forms and strong back for a guillemot L
: kayak, but have come across a small problem that I dont know the answer
: to. Ive fixed the forms to the strongback with 8mm space between the first
: couple of forms and top of the strongback but found that by the last form
: it is tight ontop of the strongback. The strong back appears straight and
: square and all forms are lined up by their register marks. Any help would
: be greatly appreicated.