Between each stringer, at the former positions is a tiny 'fabricing' rail - so there is a small gap between these 'rails' and the outer edge of the formers!
Here we go!
Yes I did - but not needed this flight.
The metal object was turned on a lathe and used to cut the centre hole in the formers. The 'Protractor' was for marking stringer positions on the formers
Will it fly?
'Tomy' timer
The sticky brown paper tabs held the 'almost cut through' former centres in place until it was time to remove the middle part of the formers.