Some hints that may be of use to builders concerning the first part of the wing
construction.
PART ONE; BONDING L.E CORES TO SPAR AND LAYUPS.
1.SPAR JIG-I made the spar jig out of 27mm MFD Board 1.2m X 1.8m cut in half to
make 2 x
(600mm x 1.8m) boards. I bolted 8 x (95mm x 20mm x 600mm) pieces of wood to the
MFD
either side, 2 per sheet to form 4 supports. I placed like bottom 'feet' on
these
supports 500mm long and bolted the two MFD boards together with overlapping ply.
I ran
diagonal supports of wood screwed to either side of the wood down to either side
of the
feet. The jig was heavy enough not to require bonding to the floor. The spar was
bonded
onto the jig at as many places as required. A space was cut out of the MFD for
the
bellcrank. There was no need to reposition the root support as per manual. Easy
levelling of the spar was done with clamps as required on either side of the
spar
down
to the bottom of the MFD board.
2. Before bonding the P3 core onto the spar I marked the required line for the
pitot/static hole and drilled the pitot/static hole on the bench, making a quick
jig to
line up the drill(secrated plastic pipe) out of wood connected to the bench.
3.I placed the pitot/static tubes through P2 and just before I bonded P2 , I fed
the
pitot/static tubes through P3. I used a different bonding technique for the
pitot/static
installation due to a different type tube and the inclusion of a static vent and
tube.
4. S3 was oversized however I corrected the angular and height differences by
floxing
in
shims at the appropriate places along the spar to line up the vertical lines on
the root
and tip cores and leading edge.
5. To cut the foam 5-6mm rib vee, I used a (20mm x 40mm x 100mm) piece of wood
and cut
one edge at 45 degree. Then scribe a 6mm line on the core foam from the
rib/edge.
Position the 45degree slope on the wood on that line and cut foam with a Stanley
knife
blade or similar.
6. I used two 3m L shaped aluminium pieces, overlapped on the leading edge to
secure
the line of the leading edge.
7. LAYUP; Placed masking tape on both spar edges to avoid dry-micro, flox,
micro-slurry
getting on the spar. Remove before coating cores and spar with epoxy.
We used 2"brushes to put the epoxy on lavishly before the bixial.
I drew, with a felt pen, a line 500mm long, in from each end on the bixial cloth
bisecting it for guidance to position onto the leading edge.
I also marked all the required positions of the layers of cloth on the foam.
Once the bixial is positioned we ran a 40cm plastic ruler on each side at 45
degrees
at
the same time to position the cloth down on the leading edge.
We wetted out with a roller and finally squeeged.
After cure, any bubbles along the leading edge were filled by drilling a hole
and
with a
syringe inject epoxy under the skin.
Port wing took 4 1/2 hours
Starboard took 4 hours
Slow hardener was used with a pump.
After cracking the wing off the spar I checked to make sure the bellcrank can
still
be
removed.
All progressed easiler than expected. On to the trailing edge cores.
Hope this may be of some help.
Cheers,
Tim
--
Timothy. P. Ward
26 Tomes Road
Papanui,
Christchurch 8005
NEW ZEALAND
PH 64033525726
Fax 64033525726
Email: ward.t@xtra.co.nz
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