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Last Modified May 30th 1997
May 1st Hmmm, this wing is going to take a bit more working out than the last one. The centre core is causing me a bit of heartache as I can't seem to get it to sit on the spar nicely and give me a true leading edge.
May 2nd No building.
May 3rd Picked up my February copy of Flyer magazine (sea mail delivery takes a while from the UK!). Miles McCallum, who is building their Europa and documenting it bi monthly in the magazine, may have fixed my core problem. Following his lead, I glued some small foam blocks onto the spar and then sanded these back to create shims at appropriate places on the spar. With the help of a couple of metal bars taped across the joins and the wooden rails that I used on the other wing I am now satisfied that my wing blocks will be correctly aligned for the layup. It doesn't sound much but it actually took me four hours to get the blocks aligned! I created a bevelled edge on the port spar trailing edge ready for the bid reinforcing tapes that will be laid on to bond the surface glass to the spar.
May 4th I undid all of the pieces that were holding the cores in place then spent the next three hours getting them bonding and aligned. Having checked that the spar was flat, the first thing was to feed the cable duct into the centre core and bond it in place with flox. Micro was spread onto the spar and the root piece glued in place and the alignment checked to ensure that washout would be correct. Flox was applied where the rib meets the spar. The aileron bellcrank nuts were floxed and more micro spread over the spar and at the points where the blocks would touch each other. Having very roughly lined this on up the procedure was repeated on the end block ensuring that the block was aligned correctly. It took very little pressure to ensure that everything was in line before pinning the guide blocks back in place. I wasn't quite satisfied how the mid block to core block was aligned at the tip so I used a bit of 5 minute epoxy to hold it in place while I applied pressure for 20 minutes while it set!! I fussed around for another half hour repeatedly checking the end alignment and the straightness of the cores before leaving them to set.
One year in and things are progressing well. For a while after Christmas I felt I wasn't really getting anywhere but now, with two partially completed wings sitting in the workshop I feel that progress is being made. I know that many builders are making much greater progress that I am but overall I am satisfied with the speed of the build. It would be very fair to say that well over half the time spent building this aircraft is preparation to build or working out the best method of doing the job. I am confident in saying that if I were to build another Europa then I could easily do the work in less than half the time it is taking me to build this one. The key thing is that I am still having a lot of fun and learning a whole new set of skills.
May 5th Got home and dashed into the workshop to see how well my core fixing had gone. I looked down the surfaces and all looked in line so I pulled off the wooden block that was running along the leading edge. Sproiingg!! Damn. That middle core just didn't want to stay in place at the joint to the inner core. The tip, without support, had moved about 1.5mm towards the underside. Time for a bit of heavy persuasion.
I sliced out the blob of epoxy from the end of the lightening hole core slot and inserted a couple of stirring sticks to force the tip back into line. I then grabbed one of my clamps and used this to make sure the surface was back in line. Having sighted along the upper and lower surfaces and checked the leading edge with my straight edge I then proceeded to apply five minute epoxy to the lightening hole core slot and the joint between the two pieces of foam before retiring for dinner. Having left the epoxy to set for a few hours I returned, removed the clamp and smiled as I looked at a lovely and straight leading edge.
May 6th Filled the gap between the cores and the spar and most of the lightening hole gaps. To keep the surface clean I stuck masking tape either side of the gap to be filled and applied micro into the gap. Once the masking tape was pulled off I then ran a small piece of plastic, angled at 45 degrees along the gap which smoothed the surface down nicely. The bottom gap on the middle core is going to need a bit of work. The starboard cores are an inch higher than the port cores to allow for the fact that the spars overlap in the fuselage. This means than there is an extra one inch wide lightening hole near the spar in the starboard leading edge cores. One inch of foam can be quite flexible and mine, at the second gap up from the spar, is sitting slightly higher than the next block at several places. Where the gaps have been epoxied they line up nicely so what I have is a series of very slight waves running along that narrow piece of the block. Measuring the waves shows a deflection of only about 1-2 mm at the worst but as the rest of the wing is looking so good I may as well fix this up.
My latest shipment from Aircraft Spruce arrived which means I can now go ahead and make up my control sticks. The sticks supplied are 1 and 1/4" inches in diameter - which means you can't fit MAC stick grips to them as these support a maximum stick diameter of 1". To get the grip to fit I will be sleeving down the inside of the stick with a piece of 1 and 1/8" 6061 tube and then inserting a piece of 1" 6061 tube to slide the MAC stick grip onto. I also bought some 1" diameter nylon rod to make the landing gear knob and some 3/4" nylon rod to make the brake handle and door handle knobs.
A quick bit of work has turned my nicely built 4:1 (100:25) resin balance as detailed in the Europa manual into a 2.5:1 (100:40) balance required when mixing the Redux aircraft adhesive supplied with the fuselage kit. For the non technical, this consisted of drawing a line 25cm from the balance fulcrum inboard of the line already drawn at 40cm for mixing resin! While I was at it I also checked the accuracy of my resin pump. It is still sitting as close to 4:1 as it is physically possible for me to measure.
May 7th I looked at the middle block again and decided that the cloth will be sufficient to hold the piece in place so I have decided to leave it as it is. I filled the remaining slots.
May 8th - 9th Only an hour or so of building on these days. I bonded on the foam block at the spar tip and sanded it back to shape
May 10th Tidied up the spar making sure it was clean and free of bumps on the outer surfaces.
May 11th Cleaned the workshop and cut the pieces ready for making the control column. I bonded in the first sleeve on each piece with Redux aviation epoxy.
May 12th Laid up the upper surface on the port aileron and fitted the inner rod into the control column. I now have a column that will fit the Europa 1.25" housing at its base and fit a 1" MAC stick grip at the top. The diagram below shows the general layout of the control column.
Before anyone asks why I used 6061 grade aluminium rather than 2024 aluminium for the new tubes, the reason I did so was because I couldn't get 2024 aluminium in 1.125 diameter! In this application the differences in characteristics is not an issue.
May 13th Sanded back the glass on the aileron layup and broke it out of the jig.
May 14th Drew the diagram shown above and wrote up my log!
May 15th Cabe down wid a head code. No buildig. :-(
May 16th Cold doing well! Spent a bit of time getting ready for tomorrow's layup.
May 17th Feeling a lot better. Starboard wing layup day. I started at 7:30am by filling the holes with dry micro and tidying up the slots. John joined me at 8:30 and while I finished the slots he micro slurried the surface. Before he had finished I had managed to make a start on floxing the ribs and he joined me to lay on the cling film that makes the rib surface nice and smooth. After a quick coffee it was time for the main layup. We applied resin over the whole surface with 2 inch paint brushes. The ones I bought this week are much better than the ones supplied with the kit as they don't shed bristles. With the surface wetted we laid on the cloth and then used stippling rollers to bed the cloth down prior to applying more resin to the surface with the brushes. As we moved along the wing we applied resin over an area, used the roller to stipple the resin in place and then squeegeed out the excess before moving on to another area. The use of the roller made such a difference to the speed of layup and the overall finish that I am going to use the roller on all the remaining large surfaces. My finishes looked good before but the finish on this layup looks absolutely fantastic. The only problem now is that I wish I had used this technique before - I suppose I can use it on the next Europa I build!! With the main cloth finished we laid up the Uni and two bid layers at the root before applying peel ply to the joints. We had finished by 11:30 and then sat puzzling out if we had missed anything as the layup was so quick and easy.
May 18th
Started the day by sanding back the glass at the root and tip. I had to do this as I had missed cutting the cloth back at the soft leather stage last night - the movie was good but it did add a lot of extra work today. I then made and fitted the brackets which will hold the wing while I do the next layup. Once the bondo holding the brackets in place was set I cracked the spar off the jig, flipped it over and moved it, and its partner, outside to scare the neighbours. It was pleasant outside so I spent a bit of time sanding back the layup to the spar edges and ensuring I had a bid of a radius on the spar edges in preparation for the bid brackets. It was then time to dismantle the jig and clean the floor up a bit before bringing the wings back inside. There were a couple of good sized bubbles within the spar at the starboard end so I flooded these with resin.
May 19th No building. I have a couple of Europa builders coming over for the evening.
May 20th Cut some bid strips in preparation for laying up the wing bid brackets.
May 21st Laid up the first bid bracket on the starboard wing. The bid brackets are two inch wide strips of bid which lock the first wing layup onto the rear of the spar. The original method of locking the wing skin onto the spar was to wrap the wing cloth around onto the back of the spare during the wing layup process. From comments made by the earlier builders I think this method is a much more satisfactory method of construction. At least it allows you to keep your sanity! I followed the manual and epoxied the glass on a piece of plastic film before carrying the pieces to the wing. The layup took about an hour to complete.
May 22nd - 25th No Building.Out of town - and to make things worse the weather was so bad I had to drive instead of flying L. Inspecting the bid bracket showed a few small bubbles on at the apex between the two faces. I will flood these with resin when I do the next layup. Considering that the bid wraps around a pretty sharp corner I am surprised how good this layup has turned out. The peel ply from aircraft spruce leaves a lot better surface finish than the ply supplied with the kit so I think I will switch to their peel ply for all future layups.
May 26th Cut out lots of bid strips ready for the remaining bid brackets. Each wing takes around twelve full length strips to complete so it took me a while to cut and roll the remaining eighteen strips.
May 27th Did a bit of sanding on the wings. The edge of the peel ply has left a small ridge which will need removing before I bake the wings prior to surface finishing.
May 28th No building.
May 29th Did the last bid bracket this evening. The spar surface was a little uneven with some areas being 2mm below the flat surface so I used a bit of flox to fill in the hollows before laying on the bid brackets. If I hadn't done this I would have had bubbles underneath the bid. All of the hollows were outboard of the aileron bellcrank and in the non stressed part of the spar which is why the spar passed Europa quality control. The Europa doesn't actually need the spar beyond the bellcrank but it does make laying up the wing easier having it there!
May 30th Tidied up after the layup. While I was doing this I noticed that some of the resin had wicked over the flanges of the aileron bellcranks on both wings. Seeing this got me thinking about what would happen I had to remove the bellcrank for service sometime in the future. I decided to remove the bellcranks to make sure they would come off if I needed them to. Having removed (and thrown away) the locknuts I tried to take off the bellcranks. After a period of cutting at the resin and prising the bellcranks away I finally got them off. Trying to do this through the aileron bellcrank inspection hole with the wing finished would have been nigh on impossible so I am very glad I decided to test the procedure at this stage. I cut back the resin a small amount to give some more clearance around the bellcrank and then remounted the port bellcrank. I am going to re prime the starboard bellcrank as the resin had wicked under this one and the primer departed from the underside of the bellcrank flange when I took the bellcrank off. Satisfied that the bellcranks will be removable in the future I pulled the cat off the pile of port trailing edge blocks which he has been jealously guarding and sat them on the spar. The strange affliction that regularly seems to affect all homebuilders took over and I spent the next fifteen minutes dreaming about actually plugging that wing into my plane and going flying. I was dragged back to reality with a call that there was a cup of tea waiting for me!
