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Last Modified August 9th 1996
April 1996
Time for workshop preparation while I am awaiting the arrival of my tailplane kit by sea. I have decided to order the plane in parts primarily because of storage. Negotiations with Carol my wife only succeeded in gaining half the garage so I have to build in stages and plan storage very carefully.
Nobody ever tells you how expensive tooling up is! By the time I had bought all the items needs to build the Europa I must have spent a good US$1200. Carol just looks skywards when I walk in with a new tool now.
The workbench. How am I going to get that workbench level and straight? Model railway construction experience helps here. A couple of wooden L girders and a 3cm thick sheet of medium density fibreboard makes a superb building surface.
30th April 1996 It's 'ere, as they say in the Europa Video. Two boxes sitting in the garage safe and well. Other than missing some screws due to being out of stock the shipment is complete. A quick check through and a look of total disbelief from my wife that I paid that much for some foam, metal, resin and glass then it's off to read the manual.
A bit of intuitive guess work has to be used to work out what each of the fillers is. The packing list refers to brand names while the manual refers to generics though does at one point refer to a totally different brand of filler that is not supplied. Not exactly helpful and a bit confusing for a first timer.
The other thing that had me scratching my head was why there were two types of hardener. The manual only refers to standard hardener yet you are also supplied with slow hardener. A quick fax to the factory got this reply from Andy Draper...
"The reason that we have supplied two hardeners is to enable you to choose the speed of cure to a degree. If you are unfamiliar with glasswork then you can use the slow hardener to start with. Larger lay-ups would be best suited to the low hardener; it is also suitable for those lay-ups which won't hold you up by curing slowly. You may mix the hardeners (before adding to the resin) to tailor the cure speed between slow and standard"
1st May 1996 Euro Chock build time. This is the practice lay-up. I carved the foam to specification and cut out my cloth. The cloth cutting takes a bit of getting used to though a pizza cutter roller 'gifted' by Carol certainly makes life easy. Having donned my safety goggles and face mask it is build time!
Messy but fun can be the only description. Every bit of cut off glass and brush hair seems attracted to the piece you are building. A combination of squeegeeing and brush dabbing seems to be the answer to getting the cloth wetted out. An inspection at the end looked good - no delaminations, no bubbles and a nice silky finish. Just like in the Rutan composites book.
2nd May 1996 Morning. Where did all of those bubbles come from? The finish looks good other than one area in the concave part of the chock where there seems to be a bit too much resin. The only worrying bit is that there are numerous small bubbles - all less than a pinhead in size but there nonetheless. Hmmm, time to speak to an expert I think. A bit more practice is going to be required before I start work on the real thing. This fibreglassing takes a lot more skill than I thought it would. Oh well, I did decide to build a Europa for a challenge after all is said and done.
3rd May 1996 I am pleased to say that the second lay-up is MUCH better than the first. The secret is good lay-ups definitely lies in the squeegee. Each layer needs to be squeegeed out thoroughly, but not enough to create delamination or white areas, before laying on the next set of ply. You also need to check the flox corners carefully at the end of the lay-up as they can hide bubbles. A quick check and squeeze out as a final check got rid of them quite effectively.
Talking of flox corners, The manual suggests using a sharp knife to cut the corners. This turns out to be messy and doesn't effectively remove the layer of micro off the glass. (The Rutan books says that this should be removed but the Europa manual doesn't mention it). I found that a really effective method of cutting back the flox was to use the Permagrit narrow cone (RF1, coarse) to cut back the foam and clean the inside of the fibreglass. You need to be careful not to cut into the glass but you do end up with a much cleaner triangle to fill with flox.
4th, 5th, 6th May 1996 Having made another practice item (and beating off requests from my son to build a new skateboard top) it was time to dive in and make a start. Cutting back the tailplane tip to create a nice curved surface was a lot of fun. My model railway experience in carving foam scenery certainly came in handy here and it didn't take too long to get a surface that I liked.
My fin core was made out of two pieces of foam bonded together and it had acquired an interesting warp during shipment. Before starting the lay-up I made very sure that it was well stuck into the jig so that I didn't have a banana shaped fin.
The fibreglass lay-up, while messy, also went well though I did forget to put peel ply over the whole leading edge and not just the end of the glass. I had to dash back into the workshop to get some on before the epoxy set! Lesson here is read the instructions very, very carefully and don't leave the workshop until you are absolutely sure that you have finished. Next morning the fibreglass looked good and, apart from a few epoxy bumps under where the peel ply at the glass edge had bulged, the finish looked fine. A bit of bulge sanding and the first job was done.
On the second side lay-up I changed my build method slightly. Instead of following the micro slurry with a coat of epoxy and then putting the cloth on I followed Graham Singleton's suggestion to put the cloth on dry. This allows you to get all of the fibres in a nice straight line (difficult to impossible when the surface is wet) and then brush through epoxy. The lay-up takes a bit longer but you end up with a really nice job. The only really tricky bit that I found was working out how to stop the fibre ends fraying around the leading edge overlap. I am still working on that one!
Having finished the lay-up, including the peel ply overlap, it was time to clean up. Never forget to clean up all of your tools. I forgot to clean up my scissors and they are now nicely encased in epoxy. Oh well.
I leave my lay-up under a 500w heatlamp overnight which keeps the surface temperature at a nice 27c. It certainly saves having to run a large heater. I have two heat lamps suspended on cords which can be positioned anywhere over the workbench thanks to a grid of cup hooks screwed into the ceiling. They are very useful for warming resin, bench top and foam before commencing work.
Sunday evening was cleanup time and this mainly consisted of once again smoothing out the area where the peel ply had been used. As well as a bit of sandpaper and muscle I found that a snap off blade insert from a disposable knife made a very good draw plane. Dragged backwards over the epoxy at 45 degrees it was possible to very cleanly remove epoxy bumps without the danger of going too deep and damaging the glass surface.
One final inspection, reinsertion of the lightening hole cores for storage, and the fin was tucked away safely until it is ready for baking.
7th, 8th May 1996 Whoever wrote this manual is a two dimensional thinker and I am a three dimensional builder! I have read this section of the manual many times yet when it comes to working out how to get the tip radius correct you realise that you really have to just work it out yourself. This method worked fine for me (not perfect, but fine). Attach the temporary leading edge piece with double sided tape. Draw a line down the centre of the rudder tip remembering that the trailing edge block won't be there when you have finished! Now draw a line down the centres of the fin trailing edge. Using bits of foam offcut align the fin trailing edge with the rudder leading edge so that the two lines meet and that the fin is more or less level with the rudder. You can now see (very roughly) the shape that the tip at the leading edge needs to be trimmed by. Put a mark on the top surface to show where the curve should start then draw a line from this mark to a point on the top surface a the trailing edge that is a distance away from the edge equivalent to half of the thickness of the trailing edge. You should have a line than is at an angle to the edge at this stage, thick at the front, thin at the back. Measure the angle, turn the rudder over and duplicate the line on the other side. The root is a lot easier as the leading edge shape is a semicircle which can be drawn with a compass.
The courage of course lies in the sanding. I didn't do too bad a job of the tip though it is difficult to judge the exact shape when you don't know exactly where the fin and rudder are going to mate at this point in the construction. I may end up having to build up the epoxy on the port side as I think my curve doesn't quite match the fin shape but I can live with that.
9th May 1996 The first surface lay-up went well. I am getting the hang of handling Uni now and the cuts ends around the tip and root are neat and not frayed this time. Dropped a pot of resin on the floor. Of course it did have to land upside down didn't it. What a mess!
I didn't mention what I do for protective gear earlier. I wear a (semi) disposable coverall made of a light breathable cloth material. My face mask is a 3M industrial mask with organics filter and pre filter while my eye protection is a full cover eye mask with foam rim. On my hands a wear thin rubber household washing gloves. Scares the hell out of the cat and the neighbours. I look like something out of a science fiction movie where bugs are invading earth. My building room has an Xpelair extractor fan which, if I wind it up to full speed, can change the air in the room in three minutes.
10th May 1996 All is not well in builder land this morning. The trailing edge support sanding back went well. First I sanded the last 1cm down to the glass using by long sanding block to give me a line to work to then used a smaller sanding spline to sand 4cm wide sections off perpendicular to the trailing edge. If I was doing it again I would follow Graham Singletons advice to epoxy a length of straight wood on top of peel ply along the trailing edge just at the end of the first lay-up. I only found out about that tip after I had finished. The bad news is that my leading edge is not straight! It is perfect until you reach a point 30cm from the tip at which point it takes on a very gentle rearward curve until it is 1.5mm out of line at the tip. The curve actually starts just at the point where my last blob of epoxy held it to the jig. Lesson:- put a blob of epoxy right on the edge of a jig when bonding pieces in place.
A quick email to my local (well 19260km actually) expert who agreed with my suggestion to leave the surface as is, lay the bid in the leading edge to the correct line and lay a few fibres of Uni in the gap to act as a filler. It's hard to describe the feeling of despair when something like this happens. The only thing that you can think of is that you have stuffed up badly and ruined your work of art.
11th, 12th May 1996 Did the second lay-up over the weekend. Mostly good except for a damned bubble about 0.5cm in diameter just in front of the flox area on the root tip. I followed the fix procedure in Burt Rutans composite guide to fix it up... Cut out the bubble, sand the plys back at a angle of 1 inch per ply. Lay in the required number of plys and leave to dry. Sand the surface flush again and you have a fix as good as new. I wouldn't have believed it if I hadn't done this as part of my practice lay-ups. It does work well and the finished surface comes up as good as new. Try fixing dents in aluminium as easy as that! The tip and root as they approach the trailing edge are a bit tricky to do though a bit of 3D imagination soon sorts the problem out.
13th May 1996 I cleaned up the first two rudder lay-ups today. There is something incredibly satisfying about this stage. You sand all the little bumps and stray bits off cloth off the end surfaces, working gradually towards a surface that looks and feels good. Something happens to me as I get towards the end of the sanding session, the lump of foam and glass looks different - it becomes part of a plane, my plane. It is a great feeling to stand back and look at what you have made with your own hands. Despite the bubble on the root and the clean up required to fix it I have a nice looking root surface and the tip and trailing edge looks good. Tonight I will bond a strip of wood into the trailing edge joggle to protect it while I am doing the rest of the rudder work, it definitely looks too fragile to be left unprotected.
14th, 15th May Have you ever wondered what happens if you make a error while working on the plane. Well, this is what happens... I made the undercut at the leading edge following the instruction to use a hacksaw blade laying flat on the surface. I popped out the foam and discovered to my horror that the wedge didn't finish at 25mm from the front but was more like 35mm. Depression follows quickly behind. Thoughts of giving up - am I that useless that I can't even get an undercut right? Now, having looked at the surface several times I see that if I follow the instructions to the word I would always end up with the cut that I have, the glass wrapped around the leading edge changes the effective angle of the cut. A fax to Andy Draper at Europa followed soon afterwards and I am pleased to say that all is not lost. He suggested that I either build the surface up to the required place with micro or, even better, make a foam wedge and micro it in place. It looks like I am going to have a fun few days making a foam wedge to fit.
16th-27th May I haven't been able to spend a lot of time on the plane over the last week or so as I have been busy with a conference. I have however almost finished fixing up the rudder trailing edge. First I cut myself a long wedge of foam that would snugly fit into to the undercut area. Masking tape was stuck to the underside of the overhang to a depth of 25mm and then, having mixed a batch of micro, I packed a bead of it into the narrowest point and laid a thin layer over the existing surface. Having done this the wedge was pushed into place and left to dry. I then mixed up some more micro and (very) roughly build up the surface to where it should be and then left that to dry. Then came the fun bit. Out with the dremel fitted with my trusted Permagrit angled bit and the grind began. Now, after some eight hours of careful cutting back and sanding I have a flat surface that is at the correct angle.
28th - 31st May No building as I have to decorate the laundry :-( before I go to England to fly a Europa :-)
