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Last Modified July 2nd 1997
June 1st Spent a bit of time working out how to align the trailing edge blocks. I have a bit of an issue with the fact that the root block is around 4mm narrower than the width of the spar plus the layup and bid brackets so I have written to the factory for advice as to how to fill this gap before the trailing edge layup.
June 2nd Jigged up the port aileron lower side and did the layup. This is a simple layup of two layers of uni so it didn't take long.
June 3rd Cleaned up the aileron layup then applied peel ply and bonded an alignment block to the section of the lower surface that will become the overhang.
June 4th Made the undercut on the port aileron and prepared the port and starboard ailerons for the leading edge closeouts.
June 5th Cleaned up the starboard wing bid layup. When I did the bid brackets I had some resin dribble onto the flying surface so I entertained myself for an hour scraping back the dribbles.
June 6th No building.
June 7th No building.
June 8th Laid up the leading edge undercuts on the port and starboard ailerons. I am finding that the standard hardener (which is all I have left) is proving to have a very short working time. I am working at just over 20 Celsius which is the lowest working limit of the AMPREG resin yet even small amounts of the resin will happily exotherm and the working time on the pieces is a lot lower than I am comfortable with. Luckily SP Systems, AMPREG's English manufacturer, have an Auckland office - one of the benefits of Auckland being the composite yacht capital of the world - so I am going to buy some more slow hardener to give me more work time. I find that a 50/50 mix of hard and slow hardeners considerably reduces the exotherm characteristics of the resin and makes layups easier.
June 9th I believe air accident inspectors call it the "chain of events". If I hadn't decided to clean the work area. If I hadn't put the aileron cores on the garage floor. If I hadn't quit the work half way and gone in for dinner. If we hadn't run out of milk. If I had used my own car instead of Carol's. Maybe, just maybe I would still have a pair of ailerons! It is amazing how much punishment an aileron can take. The body of the ailerons was fine but the car tyres messed up the hinge flanges. Goodbye ailerons, it was fun building you. They got a good burial in the rubbish bin. Once I had finished kicking myself I phoned Europa and ordered a pair of aileron cores and some more cloth. I suppose in a few years time I will look back and laugh.
June 10th Went and saw SP Systems in Auckland today. The guys there were really helpful and gave me some great tips on working with Ampreg. Bought myself a 2.5kg container of slow hardener and will use this to mix with the my remaining standard hardener to give me more work time.
Finished cleaning up the workshop, scraped off the bench and positioned the starboard flap cores for layup. As I had already made the 5mm joining block I made up some flox and bonded the two flap cores together.
June 11th The flap cores are aligned well. Having cut the jig block away where the leading edge sits I taped and epoxied the jig blocks to the work bench. Once the epoxy had set I taped and epoxied the cores to the jig block then applied peel ply as required. The instructions for this piece only tell you to peel ply the trailing edge joggle. I now peel ply all flange areas as it makes cutting out the flange foam much easier as well as giving a much better glass to glass bond in the flange closeouts. Hit a building milestone today - I have just used my 1000th metre of masking tape! I have also used over 200 metres of double sided tape, some 500 mixing sticks, 100 mixing bowls, 70 paint brushes and around 120 disposable rubber gloves! I could have cut down on some of these items but I am too lazy to clean up after the build sessions and budgeted for these items as throwaways in the cost of the aircraft.
June 12th I got a reply from the factory today regarding the 4mm gap on my wings. It appears that this is a common problem and one that is not really an issue. The flow characteristics of the wing over this area of the wing are not unduly affected by the depth of the wing. As a result it is permissible to adjust the airfoil section to fill in this gap. I intend using foam to fill the gap and shape this into the supplied airfoil shape. I spent a bit of time checking the alignment of the wing blocks this evening.
June 13th One thing that has become obvious is that aligning three large cores and one 45mm wide core on the trailing edge is not a trivial task. The 45mm core really complicates things as keeping this in line with the others is quite tricky. A bit of lateral thinking soon brought me to the conclusion that if I bond the 45mm core to the middle core then I could remove the problem without affecting the actual layup procedure. I bonded the narrow core to the middle core with micro and used masking tape to hold it in position while it set overnight. Cut the cloth for the flap surface layups.
June 14th Laid up the flap top surface then went on to have a play with the wing cores. Now that I only have three blocks to worry about, aligning them is much easier. As I did with the leading edge cores I laid on a support bar to keep the blocks perfectly aligned. I would have laid on more than one but I can't find my nails! Cleaned the workshop and came to the conclusion we have a nail thief in the house - I will have to buy some more tomorrow.
June 15th Trimmed the flap edges and re jigged the core ready for its next layup. Seeing it was such a nice day, the boys and I departed to my storage shed for the afternoon to assemble the Europa trailer. Assembly is pretty straightforward though time consuming. I need to make a couple of modifications to the trailer before it can pass its warrant of fitness and get registered. In order to meet New Zealand standards the tow bar release needs a lock mechanism to prevent it opening in transit and a safety chain needs to be fitted to keep trailer attached to the car in the event of the tow bar coming adrift. The power connector also needs replacing to match the style used in New Zealand and Australia.
Having bought another pack of nails (which means I will find my original pack tomorrow) I jigged up another couple of lengths of wood onto the wing cores. The trailing edge cores now move as a single item making the alignment easier. I spent an hour or so getting the tip washout correct while keeping the rate of change constant along the wing. I will repeat the process at the root tomorrow and with a bit of luck I will have the wing washout correct. I found that the gap that runs along the top of the trailing edge creates a slight bowing of the two inner cores. To fix this I filled the gap out with mixing sticks using between one and three sticks at various places to remove the bowing. A straight edge placed confirms that the blocks are straight along the lower surface - the upper surface won't be laid up until after the lower surface and the trailing edge closeouts are completed.
June 16th The root alignment proved itself to be a lot easier than I thought it would be largely due to the fact that I discovered that the shims I had used to keep the tip washout rate constant actually gave me the correct root alignment! Once I had triple checked this pure fluke I made a dozen foam wedges and araldited them on to the spar to replace the mixing sticks shown in the photos. The wing cores are now ready for bonding to the spar but before I do that I am going to have Alistair, my Technical Councillor come round and have a look at my aileron bellcranks as it is the last time they will be fully available for inspection.
I realised that the way I had jigged up my flap block would prevent me from wrapping the cloth around the leading edge as this part of the flap was too close to the bench. I cut the jig from the bench and reset it so that the leading edge was hanging over the edge of the bench. Didn't find my pack of nails J .
June 17th No Building
June 18th Prepared the bench and tools for the next layup.
June 19th Made up the outlet fittings for the fuel tank. The two outlets (main and reserve) each have two outlets as I have purchased the fuel drain kit. A copper tube is soldered into one of the outlets and this will be positioned into the lowest point of the tank to allow for water drainage. The other outlet takes its fuel from slightly higher up and is covered with a brass finger screen which I made up out of the material supplied with the kit. I spent a bit of time marking out my door latch parts for drilling. The door latch has two long shoot rods on each side which require slots to be cut in and holes drilled through. I have decided that this is beyond the capabilities of my tool set so I am going to have these prepared commercially.
June 20th Drilled out the door latch plates.
June 21st Laid up the second flap surface. I almost got myself into trouble on the second cloth layer as I positioned the cloth a little further in from the root than I should have before trimming it off. This layup uses the offcut to fill in a gap at the end and I discovered that I didn't have enough cloth to fill the gap. A muffled scream to Carol soon had her dashing in with 1.1 metres of cloth to fill in the gap. On return from our Mid Winter Christmas party I trimmed back the edges.
June 22nd Sanded back the edges on the flap layup then cleaned up the bench. I took a break from fibreglassing to assemble the undercarriage damper module and then spent the next couple of hours working on shaping the central undercarriage block. This U shaped piece of quite thick aluminium has to have each of its rectangular sides turned into an angled L shape. I found the easiest way to cut the aluminium back was to drill holes along the desired cut line and then saw between the holes with a Permagrit rod saw. It took a fair amount of cutting and filing to get the piece to the desired shape due to the thickness of aluminium and I have only done the first half so far. Took a break from the aluminium to cut back one of the CS Phenolic blocks to shape. These blocks are used as guides for the control tubes and, while they are supplied with the holes already drilled, require the outer edges to be cut to shape.
June 23rd Cut back the second half of the aluminium block and then polished the edges of both sides. I used 320 grit wet and dry to begin with and then finished off with 1000 grit. Having finally found a flap sander I sanded the insides of the housing that will take the control sticks until the control sticks were a sliding fit. The smallest flap sander that I could find was 50mm diameter so I had to remove quite a few of the flaps until I could get it to fit inside the housing. While I was out shopping for tools I bought myself a 12mm 1.75 thread tap for fitting the lift pins on the wings. The drill specified by Europa for this tap is 10.2mm which is a rare beast indeed. On the tap manufacturer's specification sheet the 10.2mm bit is shown as an optional drill size for a 12mm 1.75 tap if you cannot locate the correct drill size which is 13/32". A 13/32" drill bit is a lot easier to find!
June 24th Bonded the first flap plate jig to the flap and cut the hole in the surface for it.
June 25th Bonded the second flap plate jig to the flap and cut the hole. I also cut the hole for the centre flap plate. The slot for the plate gets very close to the top skin and I inadvertently punched an 11/64" hole through the top skin while cleaning the hole out. I phoned Andy at the factory to see what to do and he advised that it wasn't a problem as the hole would get filled with flox and the surface either side would already be well bonded to the flox fillets.
June 26th No building, SAA meeting
June 27th No building.
June 28th Laid up the root and tip closeouts on the flap.Laying up the first two layers on cloth on cling film certainly does make closeouts easier to do.
June 29th Finished building the trailer.
June 30th The replacement aileron cores arrived from Europa today so I jigged up the starboard core and got it ready for the first layup. I also did the wiring of the lights on the trailer. For some reason Europa provide you with cables which are exactly the right length - but don't tell you the right length for what! I found wiring the rear lights to be a frustrating exercise in working out an optimal route for the wires that would still reach the junction box. An extra 30cm of wire on each cable would have made this job simple. I fitted a safety chain to the front of the trailer and a second chain to hold down the ball clamp handle in order to prevent unplanned trailer manoeuvres at 80kmh!
