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Last Modified March 3rd 1997
1st February Laid up the bidirectional cloth
on the leading edge. The job wasn't a big one and was certainly
helped by using the the technique of doing the first layup on
cling film and then transferring it to the job. The photo on the
right shows the job while the resin is setting. The darker path
in the V groove is the hinge reinforcing layup.
2nd February Tidied up yesterday's layup. The aluminium bar took a bit of effort to remove and I ended up bending it - there goes another $10! Once I had cleaned up the surface under the peel ply I proceeded to remove the foam from the tip and root flanges. This requires a bit of patience with a sharp knife and chisel as the space is very small. I sanded back the indents where the aileron hinges will go and then did the flange layups.
The tip layup was a simple job of laying in two
layers of bid. The root however can only be described as a pain
in the ..... As can be seen from the picture, there is a plate
and nut embedded in the glass. In order for this to be
accomplished I followed the manual to the letter but certainly
didn't enjoy trying to capture two pieces of wet bidirectional
clot between nut, plate and washers and then position the whole
soggy mess into the face and flange. Much cursing came from the
workshop but I finally achieved the job and the layup does look
good. I moved the piece away and scraped down my work surface
which is now starting to look a little worse for wear. Next time
I mix up some micro I will fill in all the pot holes!
I laid up the flap rib plate during a bit of spare time this evening. This layup consists of two layers of bid either side of a 5mm piece of foam. Having covered both sides with peel ply and cling film I weighed it down under a piece of wood and left it to set. This plate will have the ribs cut out of them later.
3rd February Cleaned up the aileron layup then marked and cut out the flap ribs from the 5mm laminated foam sheet. I used a slitting disk in my dremel to do this and ended up covered in resin and glass dust. The shaping job was certainly quick but if I were to do it again I would make sure I had a vacuum cleaner running close by to catch all of the dust.
4th February I bonded the two flap cores and the rib together today. The rib was held in place by two strategically located cocktail sticks while the flox was drying. I did note that the position of the cores within their blocks was not identical at the point where the two blocks meet and if I had kept the jigs flat on the bench I would have ended up with a joggle in the trailing edge! To rectify this I pushed the edge of the inboard jig up slightly with a mixing stick and then checked the alignment along the whole flap with a straight edge. I also ensured that the washout was still correct with a spirit level.
5th February I cut out the 5mm triangle for a flox corner and trimmed back the rib until I was sure that it lay under the level of the surface. once this was done I prepared for the lower surface layup.
6th February The lower surface layup was fairly simple. The only complicated bit was laying in the flox rib as on the stabilators and trying to manage the cloth which had to be cut while on the layup in order to get both layups out of a 2.5 metre length of cloth.
7th February Tidied up the edges of the first layup. Checking the leading and trailing edges with a straight edge showed I had no warps though I do have a slight dip at the rib which will need levelling at the filling stage. I suspect that I may have made the flox mixture a bit too runny on this layup. I broke the piece out of its jig and started cutting the foam trailing edge support block for the upper layup.
8th February Finished the sanding and then did the second layup. Nothing exciting here and it was complete in under two hours.
9th February I tidied up the edges and cut
out the flange foam this morning. It took me around an hour to
get the foam cleaned out properly. I then spent some time making
up the two wooden jigs that will be used to align the flap
plates. I made the jigs out of 12mm MDF board, checking carefully
at each stage of manufacture that the measurements were correct.
Once the jigs were complete I marked out the slot locations on
the lower surface and cut out the flap plate holes. The two holes
that go into the flanges were simple but the hole that goes down
through the centre rib to reach the upper surface was a bit nerve
wracking. You have to bore this slot out with a 5mm drill bit
being very careful not to pierce the upper surface skin. What
makes it tricky is that there is very little in the way of
feeling as to when your are at the skin! I succeeded in getting
the hole cut well however.
10th - 17th February No building, visitors from overseas. Got some cross country flying in though.
18th February Spray painted the last bits of metalwork so I can now finish the wing.
19th February Mounted the aileron bellcrank under the spar. The bolts were floxed into place and the bellcrank assembly then mounted onto the bolts ensuring that Duralac was applied to the bolt heads first.
20th February No building
21st February Prepared for the flap tip and root layups. Just the usual bits of cutting cloth and getting all of the build items ready.
22nd February Laid up the tip and root layups. What a job - bid glass and I were definitely not meant to meet today! The tip layup went well but for some reason I had real problems laying up the root. One tip worth noting it that it is easier to flox the flap plate after feeding it through the hole rather than before as recommended in the manual. It is quite easy to swing the plate out from the surface and get underneath it with a spatula to apply the flox. The root layup has the flap plate and three other plates embedded in the glass. I found that the recommended cloth width was just too close to the actual width and in the end abandoned two pieces, dived into my collection of other pre cut pieces and applied a piece three centimetres wider that was much easier to work with. Unfortunately with all the trouble I had trying to get the pieces of bid to fit to shape I caused a problem that was to give me some heartache the next morning.
Damaged flap
surface (left) and start of repair (right)
23rd February The manual describes the method of removing the flap plate jigs as applying "a sharp tap" to the jig. I did this to the tip jig and the jig flew off quite easily. The root jig was another matter. I tapped and nothing moved. I tapped harder and still no movement. I tapped again and the jig flew off taking a 1 x 2 inch section of surface glass with it! While I was sorting out my bid layup yesterday some resin had flowed out through the flap plate hole and had wicked underneath the flap plate. A sawn piece of timber on a rough piece of glass makes for a very strong joint and in my case this joint ended up stronger than the joint between the uni and bid glass which must have been weakened when I was trying to sort out the bid. The break is inboard of the flap plate and over the flange area. I sanded back the break edges and created a gradient onto the good glass in accordance with standard breakage repair procedures and left that bit to fix another day when the humidity drops from its oppressive 88% level. I cleaned up the workshop and dug out some of the starboard wing pieces ready for layup.
24th February Applied epoxy blobs to the starboard wing number 2 block and cut back the edges where the flox flanges will go.
25th February No building
26th February Applied epoxy blobs to the starboard wing number 1 block and epoxied the lightening hole covers in place. I worked out a really effective method of getting my wing light conduit support blocks into place. All I did was drive a nail into the end of a piece of dowelling then, having applied a bit of epoxy to the support block I stuck the piece on the nail and used the dowel to push it into the lightening hole. As I had cut the support blocks out of the lightening hole core at the relevant locations as soon as they got to the right location they jammed and then it was an easy task to pull the dowel and its nail out of the support block. This was definitely quicker and tidier than my previous method. I shaped the rib rebates on the number 1 and number 3 cores before calling it a night.
27th February No building, Sport Aviation meeting.
28th February Epoxied another wing block and sanded the rebates.
