On a wing and a Prayer
Fine, so the tail is done, fuselage complete and time to start the wing.
At 2.3 meters this was going to be a large job
and thanks to Jeff and Steve, eventually the cores were cut
very close to the original Constellation profiles.
I then kept the outer core saddles for compression of the cores to the balsa later on.
The balsa sheets were made up of the 2.5mm sheets,
glued together with professional wood glue, compressed overnight under some books
and then all three sheets sanded down with a flat level and
60 grit sandpaper to negate any join lines prior to bonding to the cores.
The wing profile has a rather large 16 percent foil so getting the balsa to
get to the leading edge was going to be fun, but then I was going to
put a meranti leading edge on so the would negate some of the leading edge issues.
Due to the dihedral in the wing, the center panel would have to
be separate from the outer panels with a dihedral cut on the join
and then to be “bandaged” with a light glass coat and 12 hour epoxy
and then faded into the join with lightfill.
Unfortunately I do not have many photos of the early part of the wing construction
but will post what I have up to where the wing is at this point.
100mm x 2.5mmbalsa sheets being glued together – 3 sheets at a time
Pile a bag load of books on-top and leave to cure overnight and then sand flat with 60 grit paper
Center wing panel being joined with servo lead holes in place
Carbon rod through the whole affair and into the outer tips –
probably would have been better to face off the entire edge, instead of small balsa area
but went with the principal that as long as it touched both skins,
then strength would be there
Balsa skins ready for application, with wood glue – the red professional variant
and into the vac bag – cheap, available and just need a vacuum cleaner
just check for constant pressure overnight and re-apply as required
Nice tight vacuum doing the job and pulled the balsa in really well
This method was used on the center core, but I had done the outer panels the traditional
way of leaving them sandwiched under a ton of books in-between the saddles that they came from.
Still think the vac-bag came out just that bit better.
Joining the outer panels to the center core with the dihedral in place
Foam cut away and awaiting the meranti edging. A lot of people think that a hard leading edge
is a lot of work…. and it is but can be so easily improved by investing in a hand plane
that carries weight and a bloody good blade.
This I beg, borrowed and stole from Steve for a weekend and boy, what a treat.
Handplane meranti to more or less shape, tape off the balsa with masking tape to avoid an overrun,
and then take down the meranti with 60 grit paper on square edge and finally 120 grit paper
on square edge… and Bob’s your Auntie
And in the end, after a few weeks work we have a wing! Really missed out on the photies through these stages but in the end the leading edge is meranti, join is light glassed for strength…
Balsa wingtips and yes, meranti railing edge as I just hate a balsa trailing edge
of .25mm that wobbles around endlessly and curves itself to death. Meranti keeps it strong
and flat as a pan handle. Next the surfaces and the motor mounts…
ooooh kak, hier kom werk….