|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Last Modified December 15th 1996
1st November Working in Wellington, no building
2nd - 3rd November As was seen in the photos taken last month the workshop was looking a bit messy so I decided to do a clean up first. Getting the resin off the floor was quite an interesting exercise but at least it took the paint off with it! Most of the weekend was spent doing little things. I gave the metal pieces another coat of primer and continued work on the trim tabs. These can be quite annoying as they only seem to need a little work and then you realise that each piece of work requires a full day to set the resin. I used balsa wood to make up my flettner strips at the rear edge of the trim tabs. The strips consist of two pieces of balsa (model aircraft trailing edge strip suitably cut to shape) mounted so as to create a thickening of the edge. Before mounting the strips there is a small joggle at the edge of the tab that needed to be filled with micro and then sanded carefully to match the shape of the upper surface.
4th November Trim tabs
5th November Fireworks. Lots of bangs this year.
6th November Trim tabs
7th November Your guessed it, trim tabs
8th - 9th November No building
10th - 15th November No building, working in Hawaii. Sometimes life is really tough.
16th - 17th November Having decided that the last strip of the trim tab could wait I set up the jig for my port wing spar. In order to ensure that I had a good straight line I used a couple of 60cm x 2.4 metre blocks of 3cm MDF board laid on edge as the jig. These boards are supported by L shaped timber assemblies that are glued to the floor with Bondo. The spar was laid on the top surface of the jig and tacked in position with a hot melt gun while I ensured that it was level in all planes. The jig took around nine hours to build but I am pleased that I have something that is absolutely level and straight to base the wing structures on.
18th -21st November No building. This month is disappearing fast and I still haven't finished my tailplane!
22nd November Spent the evening trying to get the spar to sit on my jig without any twists. This is not going to be as easy as I thought. After four hours of patiently levelling one piece and using car body filler to bond it to the jig I gave up in disgust and went to bed!
23rd - 24th November Started Saturday off by ripping the spar off the jig and had another go at levelling the spar. By midday it was apparent that I was getting nowhere so decided to spend some time getting the wing foam bocks prepared instead, at least they don't have any major twists in them! On Sunday I spent my time fitting the hinges to the port trim tab. I stuffed up the drilling on one of the hinges so that went into the bin and an order for some more hinge went off to Aircraft Spruce!
25th November Finally worked out how to level this spar. Starting at one end you fix the spar with car body adhesive and leave it for an hour. Then you move down sixty or so centimetres and repeat the process for that point. This is going to take time. I drilled a hole for the pitot tube pipe in the root core using a piece of sharpened steel tube as a 1.5cm drill bit while I was waiting for some of the glue to dry. As I had a bit of spare time I put another coat of primer on my metal bits. Priming these parts is turning out to take time as the coating takes about a week to get hard then needs sanding down before the second coat. I have two more primers coats to put on the other side of each piece before I can put on the final coat of paint. I am now finding that there is a definite benefit to having two pieces of work going on simultaneously as it allows fill in jobs to be done while major items are drying.
26th November I now have the spar level to within 0.1 degrees in twist and dead flat along its length. A trip to the wood yard tomorrow will fix the last bit of the twist.
27th November I bought some lengths of dowel at the wood yard and cut these into lengths that were slightly longer than the height of the jig. Positioning these at 30cm intervals I then jammed them into place under the spar to correct the final twists. All is level - at last!
28th November No building. Australia for the day (and for the uninitiated, that is a 3 hour international flight each way).
29th November Spent the evening on the floor with rolls of fibreglass. I now have most of the pieces that I will need for the next couple of months cut and neatly bagged for when they are needed.
30th November I was going to lay up the wing ribs today but it is pouring down and the humidity, at 78%, is above build specification. The ribs, unlike conventional aircraft, are simply two layers of cloth laid on the side of two of the foam blocks so don't really take a lot of work to create. Instead of spending my time playing with resin I fitted the port trim tab to the stabilator. This takes patience and a lot of sanding to get the correct freedom of movement. I am a bit concerned that the trim tab has taken on a bit of a warp and that the inner part of the trim tab on the upper surface slopes from level at the hinge to some 2.5mm below the stabilator surface at the edge - a distance of only 5cm. The trailing edge is level and the underside is level so it looks like the overhang portion of the trim tab sagged while the root closeout was setting. I can't really see a way out of this other than to fill the offending dip with filler when it comes to surface finishing time. Other than that the trim tab moves freely. The manual suggests, not unreasonably, that the trim tab should be attached with the self locking metal nuts supplied with the kit. As the tab - and most of the other surfaces - will need to be removed for finishing I am a bit reluctant to use these nuts. I am a strong believer that self locking nuts are a one use item, if it gets taken off, then it gets thrown away and replaced with a new one. I bought fifty or so standard nuts and associated screws for under $10 and am using these to hold the pieces together during construction. Once the aircraft is painted and the surfaces are ready to be remounted then I will use the self locking nuts as supplied.
