March 21, 2010

Almost all finished…

… but not my best work I have to say. Anyway, after today I’ve almost finished all the work that I can do on MYRO before it’s moved to the airfield, so that’s a good thing 🙂

After yesterday’s rain, the weather forecast for today was good so I knew that this would be my first opportunity since last year to get MYRO out of the garage and do some of the ‘finishing-off’ work that I mentioned in a recent post (10th March). I wasted an hour or so by going out to buy a solderless nipple that I thought I would need to secure the end of the throttle cable. It seems these things are not so easy to find nowadays and after driving miles, I couldn’t get hold of one. Turned out that as usual, Ebay is the place to try first and save time and petrol but in the event somewhat ironically after all the wasted effort, I didn’t need one anyway 😕

The first job I did was drill holes in the new door plastics for the hinge nuts to go into when the doors are fully opened right back. I drilled small holes first to gauge the positions but even then the upper holes were still further out of position than I would ever have thought when the doors were opened right back and ended up larger than I would have liked after I’d adjusted them. The first pic shows the holes on the pilot’s side, which I did first, with the door closed and the following pic shows the door open.



Like I said, the holes will do the job, but the finished article isn’t anywhere near as pretty as I would have liked. I suppose in a way I should have expected it as it’s been six months since I did any of this kind of work and I need to get my hand in again.

The passenger’s side came out a bit better although there was something else there to think about. It only needed three holes drilling because when that door is opened, one of the hinge nuts hits squarely on one of the pop rivets holding the door plastic to the door cross brace tube. Lucky it does actually, because if it missed and hit the door plastic on top of the cross brace tube, there would be no way to drill a hole for it to go into because it would mean drilling the tube. In time it would inevitably cause damage to the door plastic. Obviously the cross brace tube is in the wrong place but I didn’t know that before. I just hope that the weight of the door on the pop rivet against the hinge nut doesn’t fatigue the door plastic and cause little splits around the rivet head, but there’s not a lot I can do about it, so there’s no point losing sleep at this point in time.

Next the door bottom stiffening brackets. The doors didn’t have these before but I’ve seen similar ones on other AX3s (both MZEL and John’s at Linton) so that confirms in my mind that they are a good idea. MYRO didn’t have them before because the door bottoms seemed fairly stiff and the door plastics hadn’t suffered as a result in those areas. However, I’d cut the tube that I made up to replace the one I stupidly snapped in the pilot’s side door a tad short and I could see the plastic flexing as the door frame tube ends moved slightly away from each other every time the door was closed. And then back again when it was opened – so it was obvious that in time the flexing would cause splits in the plastics around the nearby rivet heads. I thought that the best way to deal with this would be to pop rivet a small aluminium bridging strap between the ends of the tubes and indeed that’s what I did today.

The passenger’s side bracket went on not too badly but the pilot’s side one didn’t. Obviously that would be the one that had to go wrong because that’s the one that needed the strap the most. The first rivet that I put in didn’t sit down tightly enough, which of course, defeated the whole object. So I had to drill and cut the rivet back out again, breaking several small drills in the process and scuffing the visible surface of the bracket up with the hacksaw blade. I became resigned at that point to the fact that everything would be a bit of a battle today 🙄

The passenger side bracket is shown in the following pic.


By the way, the picture makes the edge of the door plastic look very jagged for some reason. It isn’t like that really but I’ll be taking another look at all the edges and giving them a light rub with wet and dry to make sure that they are smooth to help prevent cracks starting.

The next job was securing the throttle cable end onto the pilot’s side fuselage tube inside the cabin. This is essential as otherwise there’s no way the throttle would work when the throttle lever is activated. I was relieved when this job went smoothly and the following pic shows the finished result.


The last thing I could do before it began to get dark was deal with the screen plastic slots where the fuselage tubes pass through to connect to the engine mount attachment points. I knew after I put the new screen on last year that it was a bit tight in a couple of points in those slots but I only got to thinking seriously about it after flying MZEL last weekend.

MYRO only really had one ‘bad’ crack in the screen I had removed and Rosie had dealt with it by drilling tiny holes in the ends of the small cracks that were branching out from it to stop them spreading. So the crack was more of an unsightly distraction than a structural problem. However, last Saturday I noticed that MZEL had already developed far more cracks than MYRO had and these almost all practically without exception had starting points where the screen touched against either a tube or some other small obstacle, even a cable tie. So today I resolved to make sure that my new screen had no touching points at all.

I had to do this by trimming parts of the plastic edges away with a Stanley knife and then smoothing the edges down again with a small file. Once again the gremlins got me and I managed to inflict small scratches in the plastic on both sides above the slots that the tubes pass through. I suppose after my earlier experiences I just had to expect that such a thing might happen. The final pic below shows the slot on the pilot’s side with it’s little scratch visible 😯


And so the day ended. The next job will be to fit the second fuel tank. Then all I’ll need to do is fit the prop and refit the tail plane assembly before moving MYRO off to Linton. Can’t come soon enough I can tell you 😉