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Last Modified September 2nd 1997
August 1st Final preparation before the wing layup. This mainly consisted of masking the existing surfaces so that they won't get resin all over them when we do the layup.
August 2nd The office move - no building :-(. Remind me never to move again.
August 3rd Layup day. This layup covers the lower surface trailing edge which, to make things interesting, has four metal plates which need to poke through the cloth. John Caukwell came round to help me do the layups and we started by dry microing the holes and over the slots. We also laid a fillet of dry micro onto the surface to fill the ridge between the foam and the spar at the root end. This fillet was almost 4mm thick where the foam met the spar at the root and reduced to surface level by 10mm out from the spar towards the front and some 45 cm from the root along the spar. Having filled all the gaps we then micro slurried the surface, laid in the flox rib joints and departed for a quick cup of tea. Upon return we coated the port wing surface with resin and then tried to lay the cloth on. I say tried because we very quickly found that this layup cannot easily be done with the wing vertical. We quickly removed the wing supports and laid the wing flat on the floor then proceeded to lay the cloth on. With the cloth lying on the surface a craft knife was used to allow the cloth to settle around the metal plates. The surface was then wet out and rollered until thoroughly saturated. Two layers of bid were added at the root at which point we lifted the wing back up to sit vertically in its blocks and squeegeed the surface out. In order to get a clean finish around the metal plates I cut back the cloth until it sat neatly and then pushed any loose ends into the flox area before peel plying all around the plates and rollering the surface until it was flat. Having satisfied ourselves that the first wing was good we then started on the second wing. The layup of the two wings took the two of us just over four hours to do the layup which, considering the fact that the area was half that of the leading edge layup, makes this the most complex layup to date.
August 4th The
wings look great. The peel ply applied around the plates
certainly leaves the area very tidy and requires no further work.
I sanded back the glass along the aileron section and then cut
out the flap area with a hacksaw. To remove the foam under the
aileron overhang I used a custom cutting tool which I had made
earlier. This tool is a craft knife blade floxed to a piece of
dowelling. With the dowelling held vertically it then becomes a
simple job to slide the craft knife blade along the aileron
cutout base and slice into the foam under the cloth. With the cut
almost to the surface a quack tug at the peel ply lying between
the foam and the glass peeled the foam strip cleanly out of the
aileron cutout. It was at this point that I discovered that I
really should have bonded a metal plate to the surface before
removing the foam as I now had a very unstable piece of glass. I
applied some peel ply to the overhang with resin then sandwiched
the glass between an aluminium L plate and a piece of wood,
clamped it up and left it overnight to set. I finished off the
evening by cutting out the flap area on the other wing.
August 5th A quick trip into the workshop (while eating breakfast) to remove the aileron section clamps showed that I now have a very straight aileron edge.
August 6th - 7th
I had a look at how as was going to keep the flap section of the
wing closeout straight. This turned out to more of an issue that
the aileron section as there is a slight inward bow on both of my
centre blocks on the wing underside. The top surface is dead flat
so the bow must have been caused by wire drag when the blocks
were manufactured. I came to the conclusion that the best way to
get (and keep) this section straight was to do the opposite to
the aileron area layup and cut the foam away first allowing the
skin to adopt the shape of the straight edge. Having a good
straight edge here is important as the flap needs to sit into the
closeout without a widely tapering gap. Having cut away the foam
in the flap section I laid on an aluminium angle section and
sandwiched the skin between it and a well clamped piece of 2x1
timber. I also laid on an aluminium angle onto the second wing's
aileron section without removing the backing foam. Once these had
set overnight I cut back the backing foam on the aileron section
and removed all of the clamps. The aluminium section that I used
for supporting the edge is a length of 45mm x 25mm angle made of
3mm thick aluminium which is (very conveniently) manufactured
only 10 minutes from where I live.
August 8th Got the workshop ready for the trailing edge closeouts.
August 9th Rain. With the humidity too high to do the layups I busied myself with creating a template for the wing tips.
August 10th Did the port wing aileron closeout. I started off by laying the cloth out on a piece of cling film on the bench, wet this out and then carried this over to the wing. The cling film kept the cloth in shape as it was fed into the closeout. the reinforcing hinge areas and the second full layer of cloth were laid in dry. The layup turned out easier than I thought it would be and only took an hour to complete. To make sure nothing fell down the aileron push rod hole I stuffed a couple of rubber gloves into the hole before I started work. these will be retrieved one I make the bellcrank inspection holes.
August 11th I trimmed the cloth back and removed the metal support rail before cutting and sanding back the support block on the upper side of the trailing edge. Of course I had to have a look at how the aileron was going to sit in place so I dug it out and put it into the slot. it was at this point that I discovered I had one hinge and one fixture - the inboard hinge was locked solid. I appears that some resin had managed to wick into the hinge and rendered it useless. The fix turned out to be very simple. I sawed into the part of the hinge that I was going to remove at tang of the hinge. Then, with the hinge turned into several pieces that could move and one that wouldn't I drove a piece of hinge pin into each section in turn to release the existing hinge pin, sawing the bits off as they came out. It took a bit more effort to clear the frozen section but it too came out eventually. I then cut a new length of hinge and pin and fitted the new section in place to match up with the other side that was bonded to the aileron.
August 12th Did the starboard wing aileron closeout.
August 13th Trimmed the glass, removed the support angle and cut back the foam support block from the aileron section of the wing.
August 14th Prepared the flap section of the port wing for the layup.
August 15th No building, Stefan's 13th birthday party.
August 16th Laid up the flap portion of the port wing. Like the aileron section this turned out to be a simple job thanks to the use of the cling film though it is a bit more complex due to the fact that flox ribs have to be laid in. I cut out the foam support blocks for the aileron counter balance weights. These are made out of 38mm thick foam and have to be cut to match a set of templates supplied in the manual. I copied the templates onto thin plastic - cut up translucent plastic milk bottle provides a ready source of template plastic - and placed these on the block. I then made a hot foam cutting unit out of a 12 volt transformer, a slab of particle board, a Z shaped piece of brass and a length of Nichrome resistance wire obtained from my high street electronics store. The Z brass piece was screwed onto the board and the resistance wire stretched from the top down through a hole in the board. The power was applied and the the foam around the templates roughly cut out. A few minutes with a sanding spline had all of the foam blocks looking good.
August 17th Trimmed back the glass and then the foam block on the flap section of the wing. With the support angles removed I have a good looking wing. I had planned on doing the starboard flap closeout but an urgent phone call two minutes into the layup put paid to that and I had to go and do some work :-(
August 18th - 23rd Not a lot of building this week due to the fact that Carol fell over and fractured her elbow! I did manage to bond the aluminium support blocks inside the closeouts. These support blocks will keep the trailing edge flanges straight when I do the final surface layup.
August 24th This definitely isn't my week. I had just mixed my first lot of resin ready to lay up the starboard flap closeout when Carol came in and asked "How do you tell if someone has concussion?". Drop everything and take Nathan to the emergency clinic! Once he had been checked out and returned (albeit a bit groggily) to home, I laid up the starboard flap closeout.
August 25th Trimmed back the glass on the layup.
August 26th Cut and sanded back the trailing edge support block on the starboard flap area then bonded the aluminium support block into the closeout area. I use cleco Loc clips to hold the aluminium plates to the flange while the resin is setting. I bought thirty or so at Sun 'n Fun this year and they are proving to be very useful during the build and around the house.
August 28th Set the port wing up on trestles for this weekend's layup and applied peel ply to the flanges. With it sitting on the trestle it looks remarkably like ..... a wing! A feeling of great satisfaction overtook me and I spent the rest of the evening dreaming about flying my Europa :-)
August 29th No building.
August 30th Masked the wing and then spent three hours cutting out glass for the wing root layup.
A wing is born! Proud builder and wing are reported to be doing well.
August 31st John Caukwell and I laid up the final part of the wing surface. Other than the flox rib inserts this is a straight forward layup consisting of one large piece of biaxial cloth and three small pieces of bidirectional cloth. After lunch I laid up a few pieces of carbon fibre bidirectional cloth which I will be making into base plates for my navigation lights. I marked up and cut out the hole for the aileron bellcrank access hole in the starboard wing. To create the hole I first drilled a large hole with a hole saw then used a milling bit on my dremel to cut the larger hole to shape. I did find that the glass at the base of the inside of the bellcrank channel delaminated easily because there was only a 1cm wide strip left near the spar once the hole had been created. This wont be a problem long term as a flox pad will be created that locks the glass in place but in order to tidy things up I glued the glass back onto the foam with a bit of epoxy. in the evening I trimmed back the glass on the layup to the edge of the aluminium support bars.
