My first 2M built up plan from Mark Hunt utilized a depron crutch, depron turtle deck and lower rear deck. The formers were sandwiched 1/32 balsa depron balsa.

Plane weighed 10 lbs 6 oz with OS 160 on pipe, covered in monokote and placed 3rd in Intermediate at NATS.

see here:

http://www.insightrc.com/100_0282-B.jpg

Jusy need to be careful, depron is denser than contest grade balsa but can be lightened through milling. I used 6mm.

Chuck Hochhalter
Team Airtronics