Originally Posted by
acdii
It was an ARF and the joiner box was poorly designed. Instead of the webs going top to bottom and glued tight to the top and bottom spars, they were the same width as the distance between the spars and not glued to them. After several flights I guess the joints weakened enough that after a roll the left wing parted company with the rest of the plane.
I had pics of it somewhere. All that survived were the wings beyond the joiner box, and the fuse from the cockpit back, the rest became toothpicks.
I notice Sig no longer sells the 4*120 ARF. I wonder if there were problems with quality, or just low sales.
Regarding the 4*120 ARF I have. After a few months of use I noticed the Inner wing ribs with the tabs that attach to the fuse were separating, So I turned it into a one-piece wing, and while I was at it, I narrowed it one rib bay on each end which will allow it to fit better in my pickup, and it rolls like no-one's business.
Another problem with it were the damn CA hinges cracked on both elevator and ailerons. I replaced them with pinned hinges, but it was a butt-load of work.
Some of this is a result of powering it with a CRRC 40 engine which shakes the carp out of it.
