ORIGINAL: Charlie P.
One thing I have noticed is, I suppose because they are so short-coupled, a biplane is more sensitive of horizontal stablilzer angle of attack. Check to make sure your Hog is 0° or perhaps -1° (some negative helps avoid a "squatting" appearance in level flight). If you applied full power from 1/3 throttle and couldn't gain altitude (only speed) it seems something was keeping the nose down.
WWI bipes need about 1/2 throttle to land because of drag. Do you have a lot of rigging on the Hog?
Missed your question - sorry Charlie
The cabanes are formed from 2 pieces of shaped aluminum (each a U connected by a wood sandwich across the tops). The 2 I-struts are 3/32" lite balsa. No other supporting structure. As both wings have ailerons there is a 4/40 control rod between the two ailerons.