I just read through the instructions. Looks like a great airplane. Looks pretty strong too. I might consider doing one some day just for fun.
As for the throws, read on page 30 of the instructions-
http://www.spadtothebone.com/SPAD/De...0/page30.html. I would suggest starting with the 3/4" they recommend, then change it and make it just right for you.
Ty