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Last Modified September 11th 1996
1st August Woke up, no rain, blue sky even. Now I can let the animals out - having two of every kind in the house was getting a bit smelly and those damned unicorns kept knocking at the door. Time for a day off work I think ( there are some things that the boss can do occasionally). The second rib layup was a lot easier than the first, experience counts I suppose. Rough sanding the ply reinforcing piece certainly helps keep down the number of small bubbles on the ply. This time I didn't have to do any epoxy backfilling on the ply top though there was still a bit to do on the flox corners.
2nd August I spent the evening cleaning up the layup. No major problems here just a bit of tidying to do where the odd glass fibre had overlapped the masking tape. This is the last bit of glassing work I can do until I have the work inspected. While inspections aren't mandatory for New Zealand builders I have chosen to keep to a policy of requested inspections prior to all closeups. As the ribs will be hidden in the next stage I will wait until these are checked before bonding the two tail pieces together. I am lucky in that our local Sport Aviation Association nominated composites inspector just happens to be in charge of composites for Air New Zealand. He should know what he is doing!
3rd August Workshop cleanup and workbench sandback. By the time I finish this plane I a sure that my workbench will be doubled in weight from all the resin that has soaked into it. There were a few lumps following the last build up so a bit of elbow grease was required in order to get it nice and level again.
4th August Being an optimist and hoping that my technical advisor will be able to visit me this week I setup the jig for the next stage. Double sided tape wasn't strong enough to hold down the bend in the starboard tailplane jig so I had to use blobs of epoxy at the edges. I haven't yet had a piece of foam that is straight when laid on my bench (and yes, my bench is dead level) so setting the jigs up can be a time consuming task. I sanded the indents on the outer tailplane cores while I was at it. These indents allow the ply inserts to sit flush against the outer core. I found that the easiest way to ensure that the indents are flat was to mark the upper and lower surfaces with the correct depth of indent then sand away the foam by the lightening holes to give a good reference. Once this is complete then you can easily sand the rest of the indent away and end up with a nice flat surface.
The starboard cores had me puzzled for a while as they wouldn't sit together correctly. Having studied the surface carefully I realised that there was a small bump in the rib glasswork about 10cm back from the edge of the ply. As this coincided with the foam between two lightening holes it was stopping the two surfaces coming together. A couple of deft swipes with my sanding block on the foam surface and the two pieces mated nicely. In the pictures you will note that the tailplane is held in position on the jig with pieces of tape. This is fine for this layup but for layups where the upper or lower surface are being covered with glass I use double sided tape and epoxy to hold the work piece solidly in the jig. To stop the workpiece being damaged by the epoxy I put the epoxy on a piece of masking tape stuck onto the item in question.
5th August Not a lot to do so I cut the cloth for the next layup. I roll the cloth around a piece of 1 inch dowel (aka a broomstick) to keep it tidy. Once rolled I then use cling film wrap to ensure that dirty fingers and dust do not dirty it before layup.
I double checked the rib rebates just to ensure that I hadn't removed too much foam within the rebate area.
6th - 12th August Among the hazards facing the intrepid foam and fibreglass builder none is more feared than the domestic cat. This animal is capable of tearing holes in foam, leaving paw prints in wet resin and knocking constructed items off shelves.
It was this latter item that TC, seen here relaxing
on my tailplane, did to me. I arrived home from work on the 6th
only to find my rudder and several other items from the shelf
lying on the floor. Small cat like footprints across the
tailplane gave a clue as to the perpetrator. On examining the
rudder I found a crack and torn glass at the upper rear tip.
Luckily the trailing edge was intact so the repair job wasn't
going to be too involved. I sanded back the glass until I reached
foam then created a smooth gradient from the upper surface to the
foam around the hole. As the curve near the tip was going to be
fairly sharp I cut into the foam so I could create a flox corner.
When happy with the cut back I proceeded to layup a single layer
of uni on each side and then a further layer wrapped around the
edge. Having left this to cure I sanded the surface flat with the
existing surface. The profile of the tip has changed a little
during this process, though as this is left the discretion of the
builder anyway and still looks good, I am content with the
finished product. The is also a small scratch in one of the
surfaces (which looks suspiciously like a claw mark). This
scratch has not penetrated the glass and I will leave it up to my
advisor to decide whether I have to cut it out or fix it up at
surface finish time.
13th August My technical advisor came to see me. I passed with flying colours and can continue the building. Even the bits that I was concerned about were well within build tolerance. We actually ended up spending the evening discussing the design of the Europa which he seemed impressed with.
14th - 16th August Prepared the workshop for the layup. As this was going to be a long layup I didn't want to start it in the evening. One thing I noticed was that the TP3 temporary piece of foam that was to be laid in the rib didn't quite line up with the core. I realised that the reason this was occurring was that there were no epoxy blobs in the slots in the temporary root piece. As I only noticed this after peel plying I used slivers of modelling plastic to open up the gaps. At this piece gets removed after the layup this wasn't a problem. On the next tailplane I will epoxy the slots in the TP3 piece when I epoxy it onto the root core.
17th August Damn, fine weather, guess I will have to go flying.
18th August The bottom surface layup. This went smoother than I thought it would, in fact I was starting to get paranoid and wonder when it was going to go wrong. The first hour of the layup consisted of dry microing the slots and any dents in the surface. Half an hour was spent floxing the rib. The real secret here is cling film. Use an artists palette knife to position the flox in the rib slot, lay on the cling film and squeegee the rib. Carefully peel back the cling film and voila, a perfectly smooth surface. Two and a half hours was spent laying up the two layers of uni cloth on the surface. Using a hair dryer in front of the squeegee sure makes a difference, in fact I won't do a layup in the future without using it. Having locked the door to prevent close inspection by the cat I left the room for eight hours and then trimmed the glass edges back with a sharp craft knife.
18th August Wow! Not a single flaw, no bumps, no bubbles, no drips, no nothing. I suspect that they all won't go like this but the bottom surface of my starboard tailplane has come out like a showpiece fibreglass layup. It almost seems a shame to put filler on it.
19th August Banana time! I think that this core is going to require quite a bit of assistance to sit level for the next layup! I bonded the jig to the bench this evening.
20th August Cut the cloth for the next layup and got the bench tidied up.
21st August No building
22nd August Attempted to get the stabilator to lie straight using double sided tape. Worked fine for about an hour then released. Looks like it is going to take epoxy to hold this one in place.
23rd August I was going to bond the tailplane in position this evening but my wing kit arrived. The two cardboard boxes were packed in a very heavy wooden out case which had to be delivered by crane truck. Unfortunately the crane operator had a bit of trouble seeing in the dark and hit the house with the crane! The damage was only slight but will require the replacement of a cedar wood panel over the garage door. The kit itself is OK and the bill of materials checks out correctly.
24th August
With the help of a couple of ratchet tie downs, a heavy transformer and five minute epoxy I finally got the workpiece to sit in its jig properly. The layup went well and took around three hours. In order to get a nice straight tail edge I sandwiched the edge between two aluminium plates covered in peel ply. This worked a treat and my edge is die straight.
25th August The second layup always seems messier to clean up than the first. I had to scrape off the five minute epoxy that had bonded the piece to the jig as well as tidying up the drips and peel ply bumps. I am pleased with the finish. Late in the evening I proceeded with the removal of the foam from the root. The manual refers to this as a five second job. I have been going at it for an hour and I still haven't finished. The problem lies with the fact that resin, being the liquid that it is will creep just about everywhere including the gap between the inboard core and the root core. It takes more than a quick tug to separate the two cores once this has occurred! The inner core doesn't look too pretty at the moment but a bit of fine sanding and some micro will bring it up to finish standard again.
26th August I finished tidying up the inside of the rib and then proceeded to mark up the trim tab for cutting out. Having measured, remeasured and then measured again (for good measure) I proceeded to cut out the trim tab from the stabilator. It is helpful to add one additional measurement check not mentioned in the manual. In order to absolutely confirm that the cuts on the top and bottom surface are going to match I measured the total length of the trim tab surface and also visually checked the edge cut by kneeling down and looking at the line. When correctly drawn it appears as if you have a continuous line running from the bottom surface, over the trailing edge and onto the top surface. I used a brand new craft knife to do the cutting, running the knife lightly on each stroke until the surface was just cut through. The piece came away nicely and all of the edges are absolutely square. Unlike the root rib, cutting the trailing edge rib foam is easy. I used the flat blade out of a disposable knife, laid this flat on the foam and then cut into the foam flange. Undercutting the glass surface then released the foam flange cleanly.
27th - 30th August A busy week on the schedule but I managed to get the stabilator ready for its next layup planned for Sunday. cutting the cloth took a while but as I was setup to cut one set I did the set for the second stabilator at the same time. This layup needs to be done with the stabilator on edge so I made a mini rig using a workmate and trailer strap to keep it in place. To fill in the odd hour or two I started filing the edges of the alloy pieces from the wing kit. There are lots of bits to clean up so they should happily occupy those odd moments over the next few weeks. All that is required is a light filing with a farmers file to ensure that the edges are nice and smooth.
31st August No building. Another weekend gone. A cold southerly set in and I just couldn't keep the workshop above 20 Celsius with the extractor fan going. Filing wing bits kept me warm for a few hours. At least it isn't raining. I think I will go for a walk.
