First off – a sincere thank you to all the good people who take the time to comment on our project on the various forums… Yes, I know, the correct pluralisation is ‘fora’ but dumbing-down is the order of the day, which is why Facebolleaux has taken the place of going to each others houses for a brew. But, seriously, we do take heart in your comments because we’ve been an awful long time gaining any kind of credibility.
Back in the early days of the Bluebird Project we had all kinds of numpty museum people sucking their teeth, shaking their heads and saying none of this could be done. That to dismantle something was to destroy its history and to un-crumple was to wreck a unique ‘snapshot in time’.
I must’ve been the only person who was delighted when the Cutty Sark caught fire. Of course I didn’t want the old ship to burn but I did take much savage delight in jumping up and down and shouting about how they must leave it as it was because each blackened timber was just another snapshot.
And now… well it seems that Barra’ bashing is most fashionable and we’re no longer pariahs for our historical destruction. Very cool… and a welcome shift from the heat we were used to for so long. But nowadays it’s a new kind of heat we put up with every day because it’s chuffing hot in our workshop at this time of year and the position of, bloke on the oxy-propane torch, is not one we fight over. It was John’s turn when work started on the Clarins linkage.
For those who’ve never used hot gases to get nuts and bolts loose, here’s how it goes. We prefer oxy-propane because it’s cheap and it’s plenty hot enough for what we want so we use a neutral flame – that’s when it has neither too much propane nor too much oxygen – to bring the nut to a healthy cherry-red then we let the heat soak inwards until everything has turned black and smoky. It’s always worth cleaning up any protruding threads first, then you just pop a spanner on and wind the nut off. We bring it to the end of the thread then pick it clear with a pair of (very) long-nosed pliers to stop it skittering away under the bench or burning anyone.
If it doesn’t crack loose at the first attempt just bring the heat back up and try again. In extreme cases it may be necessary to give it a blast of cold water to get some contraction going on. One of those pump-up sprayer things is ideal but beware that steam is a gas and will come at you at near enough the temperature of the hot thing you just squirted and that can be a lot hotter than your kettle. So be careful and patient and eventually the age-old bonds will give in because all the bits will creak and contract at different rates allowing you to get things moving.
If you really want to get adventurous and scare the crap out of the H&S wombles at the same time try quenching the hot bits in isopropanol. Make sure nothing is glowing and your oxy torch is properly extinguished then drench the job. The volatile liquid flashes off as fast as you can apply it but it pulls the heat out at an alarming rate and breathing the resultant warm alcohol vapour isn’t the most unpleasant experience. Really shouldn’t be sharing this, should I…
Moving bolts within aluminium parts is a similar exercise except that nothing is going to glow. Ally will melt in a heartbeat, though, contrary to popular belief, it will show you that it’s about to go, but it’s subtle and hard to spot with the untrained eye so the most likely scenario is that you’ll go from hot metal to a liquid in a second and liquid ally is way more dangerous than hot isopropanol ever was. Aluminium is quite simply the worst thing in the world to burn yourself with, possibly excepting the phosphorous we used to nick from WWI shipwrecks, but we don’t use that when dismantling aeroplanes.
You know how if you pick up a hot thing there’s usually time to put it down or drop it before you do serious damage – not so with ally. It gives up its heat so readily that you’ll be into third degree burns before you can shout, flipping heck!
If you want to play it safe, and I recommend you do, clean it off with some Scotchbrite so you’re back to clean metal then write your name with a Sharpie on the bit you want to get hot. When you’re writing fades then disappears pack it in with the heat because you’ve hit about 500C and that’s usually more then enough for any application.
Notice above too that we’ve put a couple of nuts onto the end of the bolt. Put them down so they stand a thread or two above the end of the bolt then lock them together. You’re going to hit them with a small hammer once your autograph flashes off and they allow the blows to be transmitted through two nuts worth of threads so as not to wreck the end of the bolt because we want to put that back. Your nuts and bolts will go all soft during this process – doesn’t matter in our particular application because it’s all just for display - but if you want them to go back and actually do some work you may want to warm them up again and give them a good quench in oil or brine to put some of the strength back.
Once it was all moving, and you just have to do what it takes as many times as necessary and with infinite patience until you reach that stage, the bolts went down the pipe with a parallel punch and the shaft was released to reveal a not too bad bearing face.
Shifting the eight bolts and splitting the small shells from the Clarins Linkage took two of us about four hours but it was time well spent. Unfortunately we found out that one of the shells had pre-existing damage and it fell apart as we removed it but we have plenty of spares. This is what the inside face looked like on the linkage itself
It was immaculate under its mild surface soiling and once the bearing surfaces were cleaned up and greased it all went back together and worked just as it once did.
So with the pivot end all sorted out that only left the end where it attaches to the clamp arrangement on the olay legamabob. There, a close-fitting bolt passes through the ends of the upper fork shown above and thence through bronze bushes in the clamp and because John was instrumental in rescuing a good example from the leg from under the sea it soon become known as the John-Bolt. All well and good but the rescued example wouldn’t quite go back through the old linkage.
That’s as far as it would go because the bolt was slightly bent and the alloy was crusted with corrosion product inside the bore. There’s no explanation for the bend either because surely it didn’t get a tweak when it went sploosh… No worries, though, John reamed the hole a tenth of a millimetre or so oversize so everything would assemble easily without stressing the components. It would be a bad sketch if we broke the Clarins Linkage at this point in proceedings.
Now here’s something of note – Look at John’s gloves… they look like they belong to some ill-fated goalie from the recent world cup ball-kicking competition (I know even less about ball chasing than I do about aeroplanes, by the way) covered in scratches and scrapes that could just as easily be in his finger ends, so why is it such an uphill struggle to get people to wear gloves? Our lot just wouldn’t have it for years.
I visited a large industrial site recently where many machines turned out many machined parts – state of the art, multi-axis machining centres where the door closes with a soft hiss then seals like a telly advert for Everest double glazing before the pouring rain begins and high speed tools whiz and whirr to carve beautiful components from expensive billets. But before I could go onto the shop floor I had to don a pair of safety specs to enter a place where absolutely nothing could ever find itself flying through the air. This was after leaving the offices where people with scalding cups of coffee jostled hither and thither with no regard for safety at all. I also had to wear ridiculous, flippy-flappy overshoes with steel toecaps that made walking positively dangerous due to a peculiar off-balancing of the feet. And, at the end of it, the factory was turning out freshly machined parts covered in razor-sharp edges but did they offer me a pair of gloves when I was invited to inspect their creations?
But never mind – where were we? The Clarins Linkage and the reamed holes – well it all slipped together in a perfectly sexual way after that and in parallel with the ongoing dismantlement and rebuilding of the tailwheeleries is the similarly ongoing reassembly of the tailplane where, because most of the prep’ work is now done, matters are now proceeding with considerable industry with the top skins about ready to go back on but the last thing we want to do is stand back to admire our work only to spot a vital widget on the bench that should be inside the tailplane. A widget like this, for instance…
See that sticky-down, angley thing leaning to the left at the bottom? It’s a vital component from the Fairey Aviation Afterthought Dept. which happens to have designed most of the aeroplane and in this case a small, tubular tie-rod bolts to the end of it and to the rudder master-hinge at the other end presumably to stop it snapping off after a few had snapped off. Mike salvaged a kit of parts and spannered it to the upper extrusion of the rear spar. The rotted out steel thing on the inside is the best example we have and we’ve no idea what it’s supposed to look like or where it attaches. Must look at the drawings, or, as we prefer to call them, the instructions…
The last snagging on the lower skins is proceeding nicely too. We had to send for some longer rivets to finish the centre as there’s a whole heap of skins and thicknesses meeting in there.
Again, we’re cheating a little using blind rivets but the material is just too soft to take a rivet hammer. We’ll sort this out for where you can see and inspect the riveting but this seam lives between the top of the sticky up bit and the underside of the tailplane and is faired in from every angle so unless you break into the museum with step ladder and boroscope you’ll never clap eyes on them and if you do you deserve to be strangled to death with the drawstring from the hood of your own anorak!
One of our founder Bluebirders, Tony Dargavel, doesn’t get in to see us too often due to work and such so he adopted the other catchitt as his own pet project and resolutely picked away at the problem as and when. We had an immaculate example for the starboard side but this one was a little tired.
For those late to the party, the ‘catchitt’ is the little latch that stops the folded wings from swinging forward. The problem is that the catch part is made of steel and they don’t last too well, post crash. The best of a bad job that we salvaged for the portside became a mosaic of grafts from bits of old cockpit frame tube that ended up near as the same as the one on the other side. Eventually it was reattached to the end of the spar with two dozen 2BA (I checked the threads most thoroughly this time, Bruce.) bolts.
Notice that the wingtipamabob is finally riveted on too. We put the raggiest examples of both of these parts at this end, mainly so we could practice on the good bits at the other end first. And there’s a good reason why we were able to put the wingtipamabob on – you see, we’d first put an upper skin on for good.
Now here’s another thing, by way of an explanation. You’ll likely have noticed that the outboard skins remain a smidge battered. We’ve taken the worst of the pain out of them and yet the inboard skins, where we’ve had to make major repairs, are in better condition despite having been far more seriously bashed.
The reason is that where the outboard skins are concerned they arrived with relatively little damage so it’s impossible to say which of the dings and dents were caused when the plane hit the mountain and which were done by Clumsy-Bert on the hangar deck whilst emptying the bins. So it’s not really for us to disturb any of them if they’re not in the way of putting the rivets back. Besides, all the surviving Fairey output I’ve seen looks like it’s been dragged through a hedge backwards anyway and that’s no reflection on the love and care the FAAM boys and girls bestow on their charges, it’s just that it’s ex-war materiel and it’s had a hard paper-round. Ours will certainly look as badly used.
Then there’s the small matter of the leading edge. You’ll remember that we didn’t have a large portion of the inboard section but the outboard end was all there, albeit very slightly dinged.
Now when I say ‘very slightly dinged’, I kid you not. This, in our world, is barely scratched and a rare luxury. It took no time at all to get the worst of the wibbliness out of it.
Simple as that. It was shrunk from the get-go and came back nicely, considering that it’s only on its first round of mending here. Normally we push all the lumps and bumps out until it resembles its former self then see what needs shrinking but this time we just shrunk the bumps in-situ and watched the shape return but that only worked because it was barely scratched.
It’s always encouraging when the formers fit inside too – that’s what the red pins are all about and they went in quite easily.
Meanwhile, Gillian has been doing the fiddly stuff on the remaining skins.
They’re all glued back together now and only need a patch or two. You know you’re almost there when all that’s left to do is things like this.
What happened there is that the edge of the skin was split through from one of the rivet holes so the damaged area has been scythed away with a die-grinder and a patch fabricated. You may well wonder why such a big patch for such a tiny repair and the answer is threefold.
Firstly – when beginners (and Gillian most certainly isn’t one anymore but it’s still good practice) first start making patches they may have to, how can I put this, bugger about rather a lot until they get the right shape. The patch has to fit so it touches all the way around and gaps are verboten so starting with a sizeable chunk of scrap means that eventually, even the most ham-fisted, inept volunteer will always get their patch right at the first attempt – good psychology, is that.
The second reason is that it’s very easy to trim a patch to size after all the welding shrinkage and buggering about is done but it’s much more of a job to grow a patch that wasn’t quite big enough to start with.
And the third reason is that a bigger patch pulls the heat away and radiates it in such a way that your newly made patch always welds cleanly. Small patches are prone to evaporating under the TIG torch if you’re not careful so just make them big and they don’t.
Once they’re welded in, and we use plenty of soft filler rod to give good dilution across the weld as well as keeping a big pool of molten metal going to allow any inclusions to either float off or burn away, the excess is whisked away with a die-grinder.
Once the bulk of the unwanted material has been taken off the next stage is to hammer the welds in their newly thinned condition to stretch them and return the panel to a reasonable state of flatness before carefully dressing down to the finished thickness with a sanding disc. Loubie’s day job as a museum conservator lends her infinite patience, which happens to be most handy for this sort of work.
Then, once it’s all nice and smooth and flat, all that remains is a final fettle with hammers and such to lose any obvious trouble.
But what happens next is that we try to pin what looks like a deliciously flat panel to the tailplane only to find that it’s all the wrong shape after all and that problem must be dealt with in-situ. But that’s for another instalment.
In the meantime, there’s going to be some serious patching to do once Aerospace-Rob finishes digging out F-26. It just seems to go on forever.
It’s like some kind of nightmare, aluminium onion with layers and skins wrapped to infinity, so much so that Rob’s usually unconquerable wood-chisel and claw hammer have become dulled three times already! The box is filling with stripped parts, mind you, so we’re off to the heat-treatment plant soon. We have some alloy plates for Bluebird’s sponsons along with a bunch of twisted, steel attachment angles from her ripped out front spar. Then we have half a vanload of Baddacooda and a few tubes of very mashed Hurricane to go too, all to be made soft as butter so we can push it about.
With a little luck this will all be done by the next diary entry and we’ll have the top of the tailplane boxed in too. No rest for the wicked so until next time…