28. Fabrication 2
We last visited our welder, Allen Haseldine, in episode 16.
Now it was time to go again.
Getting to Allen’s is an adventure in itself, since the last half our of the journey is on single track roads, and there’s no mobile signal. It’s not absolutely essential to have four wheel drive though you feel it would be a definite advantage. And if you put the postcode into your GPS, you’ll end up about a mile away.
But once there, the door’s open, the kettle’s on, and you’re made to feel immediately at home.
And we worked. Boy, can Allen get through some work. On Wednesday we were in the workshop solidly for 11 hours, and on on Friday for 8 hours. Welding takes a very great deal of concentration, and for Allen to be able to turn out so much work of such a high standard was truly amazing.
The tailpost is right at the back of the fuselage – it’s the bit the rudder is attached to – and has to be perfectly aligned; everything has to be perfectly at right angles with everything else, and the rudder hinges need to be exactly the right distance apart. There’s a strange strip of metal that’s shown on the drawing doing more or less impossible things, and we needed to make some slight changes to enable it to be manufactured at all, but it all went okay in the end, and the finished article was absolutely spot on.
Having done that, we needed to set up the attachment of the tailplane to the tailpost – again, everything had to be exactly square.
There was a slight difficulty here. There are a couple of struts from the bottom of the tailpost to the back of the tailplane, and a piece of metal has to be wrapped round the tube, and the ends joined together by welding.
The problem is that the right angle bends at the bottom have to be done before you wrap it round the tube, and so you’ve got to get them exactly the right distance apart.
Having done that, it’s then pretty skilful stuff welding the edges of the clip together without welding it to the tube. Then finally you have to adjust the lengths of the struts and the distance of the clips from the centre, and make sure everything’s the same on both sides, so that everything’s perfectly square before brazing the clip to the tube and putting the taper pin in.
Anyway, to prove the whole lot worked okay, here’s a picture of the whole assembly. There are some pins to put in, and ribs to be fitted, but that’s the job for next week.
I guess that was the most stressful part of the two days, but we kept Allen hard at it all the time.
The other major component I was worried about was the bits at the bottom of the undercarriage, where the legs join together and the axle goes through. In the end it was pretty straightforward thanks to the excellent drawing by Derek Walton and very careful preparation by Rick and and the end result was pretty impressive.
Here’s a picture of the end result of our labours. Pretty good, eh?