Buzz Bomb Update

Construction is progressing well on my new Stevens Aero Buzz Bomb. All of the balsa wood aircraft structures are now complete and ready for a final sanding. Covering and installation of radio equipment and the motor will be the next building agenda items.

Buzz Bomb fuselage nearing completion

Buzz Bomb fuselage nearing completion

The kit has gone together exceptionally well to date. The only issue that I ran into regarded alignment of the wing tips. The model uses a polyhedral concept with the outer third of the wind having extra dihedral to provide lateral stability. This was a very common technique in the early days of free flight model airplane in an attempt to come up with a more inherently stable design.

Initial construction of wing center section

Initial construction of wing center section

The issue with the kit is that the wing end sections are butt-glued in place to the end of the wing inner section. The outer third of the wing is dry assembled. It is fairly easy to have a wash in or wash out twist, whereby the wing’s outer section is not aligned with the inner wing sections. This is evident when the wing is carefully laid flat on the building board.

Luckily I spotted this early on. I made a few breaks where the wing tip section was glued to the main wing, aligned back to the proper incidence (no wash out, same incidence as the main wing panel) and glued in place. The follow on installation of the upper stringers made the entire structure complete and strong.

View of photo illustrated Buzz Bomb construction manual

View of photo illustrated Buzz Bomb construction manual

Bottom line, for a three channel model such as this (i.e. no ailerons) where the wing is constructed in three segments, ensure that the completed wing is flat and at the same incidence. Note that any final adjustments on the wing’s incidence can be taken care of with final sanding as well as even installation of the heat shrink covering.

Do note the photo illustrated construction manual, a standard feature with all Stevens kits. This covers every single step with a dedicated photo and clear instructions of what needs to be done. The manual is so thorough that full size plans are not included, really quite amazing for any kit. But the unique Stevens Aero interlocking build process works out just fine.

 

Completed Buzz Bomb wing structure

Completed Buzz Bomb wing structure