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Last Modified July 1st 1998
June 1st Set up the stabilators so that the second trim tab drive pin could be bonded in place. To ensure that the stabilators were in line I inserted the torque tube between the stabilators then clamped them together with two angle plates running laterally. The TP5 drive arm with the TP6 sockets was used to establish the position of the second pin which was then bonded into place. A third angle plate was used to clamp the trim tabs in line and the whole assembly left to set.
As I couldn't do anything at the rear of the aircraft due to the fact that the torque tube was otherwise occupied I decided to (literally) attack the front of the aircraft. The firewall and underside gets cut back to allow the wheel and engine mount to be fitted. I started underneath the aircraft, cutting the base away with my dremel and permagrit slitting disk. This is a task not to be approached without a fully protective suit, goggles and face mask as dust gets everywhere! With the hole more or less cut out I then slit open the firewall. The edges were quite easy to trim back using a combination of slitting disk, sanding drum and hand spline. I haven't yet established the shape of the back of the undercarriage hole but that will wait for another day.
The next task was to drill the two lower holes for
the engine and undercarriage mount. The manual is rather
indefinite about the position of these holes so I started off
drilling two small holes and then used a file to expand them. The
fit of the frame is very tight in the fuselage and the
holes required quite a bit of work until I could get anything
close to a fit. I had to trim the top of the tunnel slightly as
there were some resin lumps impeding insertion at the top. Once
everything more of less fit I drove the frame into place with a
hammer that was well buffered with a block of wood. I found that
the frame was being hindered at the base by the diagonal braces
and wasn't able to achieve the 1.5 - 3mm firewall spacing so I
ground a small groove into the apex of the firewall and tunnel so
accommodate the diagonal tube. With this done I inserted pieces
of 3mm ply behind the tube to definitely establish vertical and
horizontal positioning and drove the frame home again. The base
holes are somewhat larger than the tube as a result of
experimenting with positioning though these will be filled with
Redux and flox later. Now that I have experienced how hard it is
to get this frame in and out of the fuselage I can see how it can
support the aircraft with only eight bolts!
June 2nd
Having separated the stabilators and extracted the torque tube I
turned my attention to the rear of the aircraft. I drilled out
the two torque tube holes with a 2 inch hole saw and inserted the
torque tube and stabilator drive plates. It is important that the
tube is level and aligned parallel with the firewall. Mine is
down to starboard by 0.4 degrees and is aft to starboard by 3mm.
This misalignment is allowed for in the build process and will be
corrected with a little bit of filing.
June 3rd Filed and tested the fitting of the torque tube.
June 4th Ditto!
June 5th No building
June 6th Bonded in the torque tube. This has to be done as a two part job otherwise you end up with a sticky mess. The first part of the bonding is done on the inside of the fuselage and this proved to be a simple task though the alignment did need checking regularly (or was I just being nervous!)
June 7th Now that the bushes were locked in place the TP12 plates could be drawn back and the outside bonding flange was made up out of flox and redux. I then proceeded to setup the inner plastic rings that prevent the torque tube from moving horizontally within the fuselage. This was a fairly simple job though I did end up with a bit of play on my first attempt and followed the manuals instructions for fixing the problem (obviously this is a fairly common occurrence!). The inner drive arm was reinserted onto the torque tube and the whole assembly put in place to have the pins inserted. Everything fitted nicely though a tip here is to make sure that the locking clip holes within the pins are vertical otherwise you will need to have very flexible wrists to get the pins through the holes. Before I slid the TP12 plates into their final positions I greased the shaft as the bearing had stiffened up during the build process. The grease freed everything up nicely. I also applied grease to the torque tube arms before grabbing my stabilators and sliding them into position. I was surprised as to how much of the stabilator flanges I am going to have to remove to get them to sit in the correct position with over 1.5cm needing to be cut off each one. I will do the trimming during the week while I have a bit of spare time but while the garage was clear of Carol's car I primed the pitch torque tube and the trim push rod.
June 8th - 10th When I was working on my wings I pondered the question, "What do you do if you trim the flanges back too far"? An interesting dilemma as you would have to extend the edge of six or so layers of glass with nothing to back it. Well, I now have a method of doing it! Having carefully measured how far I would need to trim back the flange on my port stabilator I took out my dremel and slitting disk and cut the flange back. I slid the stabilator back onto the tube and groaned as a looked at a gap that started off slightly narrower at the rear and got gradually wider towards the front. By the time the gap reached the leading edge it was 3mm wider than I wanted so I needed some way of extending my flange by 3mm. At last, I said, an opportunity to see if my flange fixing method would work. (Well it was something along those lines, though for some reason the cat decided to depart the workshop!).
Step 1: Scuff sand the inside of the flange. Makeup a 2 bid sheet and cut it to 2cm wide. Lay this on the inside of the flange with 1cm against the flange and 1cm overhanging. Leave to cure.
Step 2: Scuff sand the outside of the overlap layup and the edge of the flange. Make up a fairly thick mix of flox and, using the overhang as a backing build up a layer slightly thicker than the thickness of the flange. Leave to cure.
Step 3: Using a sanding drum in a dremel sand the surface of the flox to match the surface of the stabilator.
Step 4: Very carefully, and a bit at a time, trim the extended flange back to the correct size. Stand back and admire your handiwork.
Step 5: Promise yourself never to do it again.
Ordered my Rotax 914 engine today. I have added the 40 amp alternator option as I was starting to get too close to the built in generator maximum output of 18A with the electrics I have planned. This wouldn't be a problem for Europa's configured for day use only but mine also has strobes, position light and landing light which all gobble up current and the extra power gives a nice buffer. [Subsequently cancelled as the Rotax alternator add on does not fit in the Europa cowlings].
June 11th
Finished off the port flange and did the starboard flange. The
starboard side only took me half an hour! Somewhere in my build
process I have ended up with a 0.3 degree difference in angle
between the port and starboard stabilators which I don't think is
critical but is damned annoying. The only way I can think that
this occurred is that the pin holes in the torque tube weren't
drilled quite in line by the factory and that I have the tube
assembled the opposite way round to the way I had it when setting
up the stabilators and had them perfectly aligned. When I feel
patient enough I will extract the torque tube and try it the
other way round.
The next stage of the build process is to fit the pitch push rod. This needed to be cut to length so I set the control column at its centre point and the stabilators level. Stefan and I spent half an hour trying to screw the pitch tube, which already has one end fitting in place, into the pitch cross tube within the cockpit module. After the half hour we came to the conclusion that something must be wrong with the rod end fitting so I dived into to cockpit module to remove the fitting. This was made possible by the fact that I had already cut out the wheel well underside otherwise it would have been an impossible task. I checked the rod end and found that there was a bit of metal flash within the thread that was preventing the thread from entering so cleaned it up. Next time I will check rod ends before they get fitted! With the rod end back in place the pitch tube now screwed in easily. The other end fitting was slid into place within the tube and marked before removing the tube from the plane and cutting it down to size.
The plane has obviously become part of our family's life but nothing has driven that fact home more than something that Carol asked me last night. She wanted a picture of a Europa that she can carry around in her handbag so that when her friends ask her about the plane she has something that she can show them! I gave her a photo of G-ODTI that I took a year ago in Kirkbymoorside just before its first flight. I am not sure what to think when your wife carries around a picture of your plane - but not one of the builder :-)
June 12th
Drilled out and fitted the pitch tube end fitting then sanded
back the tube ready for final painting. Heard from Europa that
the shipping company will replace the damaged parts from my
recent shipment. It will take a while for them to be freighted
out by sea but I can live with that. At least I can get rid of
the big cardboard box that has been sitting in my workshop!
June 13th Did some shaping of metalwork then painted the pitch tube, the trim tab tube and the counterbalance assembly. I ran out of System 3 primer a few days ago and have now switched to Zinc Chromate. I don't like the hazards associated with Zinc Chromate but it sure sticks to metal! I then cleaned up the workshop and discovered it does have a floor! I spoke to Roger at Europa who said (in a voice that clearly reflected the fact that he thought I was being a paranoid), that 0.3 degrees offset between the stabilators was not going to be a problem. I am going to leave them as they are.
June 14th
Fitted the pitch tube. It would have been better to have the tube
one more centimetre longer in order to give me a bit more buffer
around maximum up pitch. The manual doesn't tell you how to
position the pitch control when cutting the pitch tube using the
words "as required" instead. On my next Europa I think
I would put the control hard back against the stop, stabilator to
13 degrees up, rod end fittings to mid point and then measure the
length of the pitch tube. This would give a clear 1 degree of
upward movement buffer that could easily be removed with an
inward turn of the rod end. I dived under the plane to finish
cutting the wheel well. I made a semicircular template out of
paper, positioned this within the well and used it as a guide to
cut out the back of the well. Back to the tail of the plane where
I cut out the slots for the trim tab drive arm.
June 15th No
building. I did spend some time with my manual bringing things up
to date. While building it is important to keep track of where
you are so as each paragraph is completed it gets ticked off in
the book. If there is any section within a paragraph that has not
been completed at the end of the build session then I place a
stick on tab to mark the paragraph for further attention. Of
course it is also important to keep track of which page you are
up to within the manual and for this I use one of these cat
shaped book marks, several of which can be conveniently found
around our house sitting on anything other than the floor.
Part of the next build phase is to set up the tailwheel. Well it would be if I wasn't fitting the new tailwheel. This now leads to a catch 22 situation. You can't set up the rudder pedals until you have set up the tailwheel and you can't set up the tailwheel until you have the fin closed off and you can' close the fin off until you have the top on and you can't... ... ... ...
So. I have decided to fit the original tailwheel
support bracket but to save me the trouble of filling a large
hole on the underside of the aircraft should I decide to modify
the wheel support bracket. I have trimmed the original tailwheel
shaft back to the bearing support weldment. This allows the
tailwheel support bracket to fit within the aircraft without
having to cut a hole in the fuselage surface. I used the words
"should I decide" as there is a school of thought that
it would be best to keep the support bracket in place to
dissipate the stress onto the rear bulkhead in case the pilot
pushes down hard on both pedals simultaneously. I mentioned this
to Alister last time he was round and agreed with that opinion.
His statement was that few people realise how much pressure the
body can generate on a set of rudder pedals and having something
to transfer that stress away from the rudder bearing where it
would be applied in the standard Europa modification would be a
good idea.
June 16th - 19th Drawing electrical diagrams for the plane. As I am a network designer by profession, diagramming the electrical system for my Europa is a pleasure. I am probably doing a bit more than most builders will do in that every wire in the plane has a unique identifier and a net list is being created for the plane.
June 20th I have a new contender for the messiest layup on the plane! I laid up the brackets that wrap around the wheel well onto the fuselage. As these are done with the builder lying upside down there is a real opportunity to make a mess! I didn't do too bad though the layup took a lot longer than I had expected it too. While the layup was drying I drilled the holes in the landing gear frame. I had hoped that these could be done with a bench press however the shape of the frame precluded that and I had to drill the holes by hand. I spent some time making up the small sub assemblies that will be used in the next phase of construction.
June 21st With the glass now dried around the wheel well the next challenge was to extend the holes I had drilled in the frame into the fuselage. Having first positioned the frame correctly in the fuselage with a 3mm gap between the frame and the front of the firewall I marked out the top holes. Using a tight fit drill attachment I drilled the top holes through the cockpit module sides using the frame as a guide. Drilling the bottom holes proved to a bit more of a problem. The first issue was that the tight fit drill bits weren't long enough to go through both the tube and the wall as there is a 2mm gap between the tube and wall at this point. The other issue was that on the forward holes I couldn't even get the drill close to the hole due to the proximity of the fuselage floor! After some considerable puzzling I solved the problem. First task was to fit the drill bit into my drill the wrong way round. I then mounted the drill in my bench vice and, using it as a lathe, ground down the drill bit shaft until it would fit into my Dremel flex shaft. having fitted the drill bit into the flex shaft I then used this to drill the holes out. The Dremel and the drill bit complained bitterly throughout the process but it did the job. Due to the gap between the lower tubes and the cockpit module the AN3-13A bolts supplied are too short so I am going to have to buy some AN3-14A and AN3-15A bolts to do the job. The gap will be filled with Redux and flox prior to tightening the bolts so the key factor here is to meet the requirement to have at least 1.5 threads of the bolt showing above the nut.
The frame was removed from the fuselage and the retraction lever arms and associated shaft fitted to the frame. Two bearing blocks get fitted inside the tube and the shaft packed with grease prior to the fitting of the retract arms. The fitting of this shaft proved to be quite tricky as it is a very tight fit. There was one point when I thought that I had applied too much loctite to the fixture and turned the shaft into a stationery object but it did in fact free up. I packed the hole with grease and then fitted the shaft before adding the end arms. Again these arms are a tight fit onto the shaft and it took several attempts before I could get them fit. The fitting process for the frame is now taking a bit of a break as I can't find one rather important piece of tufnol so I have ordered another piece from Europa. I have absolutely no doubts that the day after the replacement arrives I will find the original in some obscure place where the cat hid it!
Lots to do in the meantime. Two floors for the rudder pedals have to be made up out of plywood. These are rather awkwardly shaped so the first thing I did was establish the shape. I marked out a strip of wood with 0.5 cm markings and also drew cm markings along the lip on the cockpit module front where the floor will rest. Ensuring that the wood was level I then recorded the profile at 1cm increments and transferred these measurements onto a sheet of cardboard. This piece of cardboard was trial fitted and a second template made with the adjustments incorporated. I was pleasantly surprised to discover the footwells on both sides were of identical shape (never assume anything when it comes to fibreglass!) so I transferred the shape onto the plywood.
June 22nd I discovered a gotcha with the rudder pedal floor alignment. I had measured the holes for the rudder pedal shafts and drilled them out some time ago. While I was preparing to bond in the foam supports for the rudder pedal floors it struck me that there was nothing in the build procedure to ensure that both floors were level with each other. I laid a metal bar on the base of the holes and surprise, there was a 1 degree variance in height across the width of the wheel well. To fix this I bored down the starboard side until it was level with the base of the port side - a depth of around 3mm. I then bonded in the foam on the starboard side and left the micro to set overnight.
June 22rd Using the starboard foam as a datum I projected the height over to the port side by placing my steel rod on blocks and ensuring that it was level. The port foam was bonded in place using this datum and left to set. I now have two sides which are absolutely level longitudinally and laterally as well as being in the same plane vertically. I trimmed the wooden floor for the starboard side to ensure that it was a good fit within the well.
June 23rd Trimmed the port footwell floor.
June 24th Cut out the cloth for the footwell layups.
June 25th No building, SAANZ meeting.
June 26th Laid up the cloth on the undersides of the footwell floors.
June 27th Trimmed the footwell floor layups and taped them in place. I then assembled the rudder pedal assemblies to check that everything was going to end up in line - they will. I decided to attack some metal and turned my attention to the retraction level plate. This needs a 7mm slot to be cut into the centre of the plate. I must admit that I was dreading doing this. I centre punched points all along the slot location and then drilled each point with a 5mm drill before filing the slot out. In the end it turned out to be a really simple job and my old metalwork teacher would be proud of the job. No, he would be amazed.
June 28th The
throttle lever requires a simple surround to be made out of
glass. I made up the basic shape with spare blue foam then laid
up four layers of bid over the foam block. While this setting I
spent some time underneath the aircraft revisiting my inspection
panels. The rudder cable is going to pass very close to one of my
existing nut plates so I relocated one of the plates on each of
the inspection panels to give some more clearance.
June 29th Trimmed up the throttle lever surround, drilled the holes and cut out the foam from within the mould.
June 30th Fitted the nutplates to the flanges then made up some surface filler and covered the outside of the shape. Primed the last of my metalwork and did some more sub assembly work. The hardest task of the day was bending the undercarriage retraction arm. I was not sure whether the arm or my wrist was going to give way first but I won in the end. Cut out the slot in the cockpit module for the retraction lever arm.
