The design report

Fuselage fabrication 5.2
Since there were two fuselages, it was decided that it would be wise to start with the
first one and get familiarised with it, then start with the second one. This is very useful
as there may be mistakes during manufacture the first fuselage and the mistake could
actually be corrected without wasting additional material. A couple of mistakes were
found while making the first fuselage. For example, the two top plates were made
exactly the same initially in CATIA. During the fabrication process of the second fuselage,
we found that the bottom plate did not fit as there were locking mechanisms stopping it
from clicking in. The bottom top plate was then cut out so that it could easily slide
through the ribs and not click in like the top one. Realisation occurred at the time about
the fact that processes in CATIA does not necessarily ensure fabrication success
The order of the fabrication was fairly simple. CATIA files had to be converted into .dxf
files and rearrange all the parts in AutoCAD to fit the given dimensions of different
materials that we were using. The files were then run in the laser programme and the
laser will cut the exact part out for us. The problem with this part is that some of the
planks of wood were not entirely flat so there were minor errors when the laser
machine was cutting the parts. Those errors were small enough to neglect so it did not
cause a big problem. It had to be ensured that tiny parts were required to cut, as it
might fall through the gaps under the planks. It is best to slide a thin sheet of used balsa
to stop that from happening.
The fuselage design consisted on many interlocking parts to ensure all connectivity was
well secured. Gluing was only a secondary process of connection and only in place to
avoid slipping.
The design of the fuselage had readymade slots for everything to be locked together so
figuring out the actual position of each rib was not at all a problem. Extra effort was
taken into strengthening the connections, for example, the centre plate and the
longerons that had to be split into two due to the restriction of length were to sandwich
it with two carbon strips on the joints. That would have ensured that the joining of two
would not split apart during flight or when carrying a load.
After gluing everything into place, the fuselage was to be left overnight to dry
completely. There were three different types of glue that we used (AB Glue, Superglue,
PVA Glue). Each glue needed different amount of time to dry so it all depends on which
glue was used. PVA glue was the glue used for parts that did not do heavy duty work
and superglue was the glue when you needed something to be in place instantly while
AB glue was the strongest of all and it was to be used on parts the take heavy loads.