There’s a thus-far unsung hero involved here that you ought to know about. You see, what happened is that we needed to push bends in long panels and we simply don’t have the facilities. Although my factory is next door to the BBP shop, and metal-bending is what goes on in there, most of what we make you can hold in the palm of your hand so bending a 2m sheet is a problem.
I called Alan from Leengate. Alan has been extraordinarily helpful not only in supplying welding materials but also with his extensive knowledge of old material spec’s and how to weld them. He straightaway pointed us at a company called Kirkdale 2000. (http://www.kirkdale2000.co.uk/About%20us.html)
Remember when Carl fitted our heating system and Balmoral Tanks supplied us with that smart, green fuel tank… Well that tank was made in a huge mould into which powdered plastic is poured before the whole affair is heated to melt the plastic then tumbled about to spread it evenly around the inside. Once it cools you can take the lid off and you have a plastic tank inside. Guess who made the mould. Here’s another one in the making.
The guys at Kirkdale are tin-bashing heavy sheets of steel into these amazing shapes. It’s similar to what we’re doing only on a grand scale with much heavier material and they’re bloody good at it!
We were introduced to Drew West, the main-man and a thoroughly good bloke who immediately offered to help out if he could.
So Saturday morning found John-Tidy and I in Kirkdale’s workshop where Drew very kindly and expertly set up a bend for us…
…then gave it a shove.
Pic © John W Barron 2008.
He got it absolutely spot-on at the first go and it literally fell onto the boat, but more of that in a mo.
Work didn’t slow down because John and I had sneaked off, not a chance. The Novie-taxi had screeched to a halt earlier and disgorged several fresh pairs of hands into the fray so while Novie slapped Chemetall-Trevor’s miracle paint remover over a large floor section, Doddy set about finishing that blister from the port side.
Young Greg, in the meantime, tank tested his model for a future water speed record contender.
He’s well under forty so what he was thinking of we have no idea but it floated disturbingly well.
In the other workshop, Rob was bashing away at the air intake. What a complicated beastie that is; especially now that it’s a bit tweaked here and there.
The 66 mod’s following its in service failure are extensive and a belt-and-braces approach to the problem. It’s little wonder Donald’s crew had to slap a pile of lead in the back of the boat after what was riveted into the front! And here’s an interesting theory for you – and it is only a theory at this stage.
You know how history has recorded that when the intakes let go during a static engine test in the winter of 66 the engine ingested a load of rivets and trashed itself – well I reckon that may be slightly wrong.
Two reasons.
One, there aren’t many rivets in there in the first place, perhaps for that very reason. The intakes are a big, fabricated lump from one end to the other with only a handful of rivets on the inner surfaces. But… it does contain large quantities of some sort of glass-hard epoxy filler that’s been slapped into every crevice seemingly with a trowel.
We first though it was pieces of Perspex from the canopy or spray baffles but it’s not. They must’ve got a bucket load of it for free.
Now then – were the intakes to collapse internally you’d probably get a few rivet heads going down the spout but perhaps, more significantly, you’d get a shedload of this epoxy stuff too and it’s easily hard enough to scar a compressor blade. No doubt we’ll learn more as we carry on dismantling.
Here’s another interesting snippet.
Remember Donald waxing lyrical about ‘advanced engineering, rocketry, what have you…’
He forgot to mention the plywood keeping his spray baffles on.
It’s these tiny fragments of history that bring to life the human side of that thankless struggle under canvass in the winter of 66/67. Wonder who cut and shaped that piece of wood, or who decided it was the answer in the first place.
Back to the tin-bashing; we brought our beautifully formed panel back to the workshop and set about making it boat-shaped.
Doddy has done a bit of wheeling in his time. He wheeled a hundred-odd panels for those golf balls at the Fylingdales early warning station, for example. (http://www.fylingdales.ukf.net/views.htm) So we judged him up to the job and got going.
Wheeling with the great ‘Doddy’.
It was the first time we’d opened the big door this year too (the skin panel was too long to do the job with the door closed) but it was windy outside so dust swirled in and landed on our sheet of alloy.
Hearing the gentle crunch of bits under the wheel, John attempted to dust it off on an ongoing basis until Alan pointed out that he’d only catch his thumb between the wheels once. The dusting stopped quick as you like and soon thereafter, K7 took delivery of her other side.
Told you we’d have a quick finish on the port side, notice that we’ve chucked the blister on there too. There’s some snagging to do on the main spar-box and a repair to the back of the flute but otherwise we now have both sides. Target now is to get her upside down and rebuild the floors.
Considering that we have everything intact (floor-wise) from the tip of the bow (F-23) to the cockpit bulkhead (F-15) with Airframe Assemblies having reworked the cockpit floor, and likewise with the stretch from F-1 to F-10, that leaves us only five stations in the middle unaccounted for. Of course, that happens to be one of the more complex floor sections, but the material is sourced and inbound. Kirkdale can push the intricate bends for us and we’ll spanner it all together at this end.
The floors promise to be a real challenge because, like the sponsons, it’s critical that we get them right. The amount of leverage transmitted from those outrigged planing surfaces to such a slender hull frame requires little imagining and at very least such torsional flexing will cause rudder deflections. But imagine if it popped the heads off a few rivets and how quickly disaster would ensue if the corner of a skin yielded to air or water pressure.
Go to the AAIB website and look up the Lockerbie 747 accident report. From memory the bomb went off in the lower left corner of a forward hold just aft of the cockpit and fired a crack over the top of the fuselage all the way around to the right-hand window belt. The outer skins were instantly stripped off by the airflow as far back as the wing but still the aircraft flew, held together by its decks; but not for long because the explosion disrupted the floors and caused a violent control input via the underfloor runs. The cockpit immediately broke off as a result, departed to the right knocking the number 3 engine off its pylon as it went and still the work wasn’t done because the remaining three engines let go too. And the time frame for all of this… four seconds! http://www.aaib.dft.gov.uk/cms_resources/2-1990%20N739PA.pdf
I think we’ll make sure the floors are properly fixed… And to that end we have some experimental and extreme conserveering lined up for later in the week.