December 2012

Yet another diary! I hear you say…

Yes, and the last of 2012. We’ve had a good year in our little workshop with a great deal achieved. Our engine systems are all working, albeit in need of some finishing off and testing, and our upper covers are built and the staggeringly complex conservation – or rather, ‘conserveering’, job – on the air intakes is now complete, more of that below.

People are forever asking us when we’ll be finished and the answer is… 2013. And if you believe that you’ll believe anything. The more astute amongst you must have, by now, spotted that we use the gentle subterfuge of ‘telling lies’. Think about it – had we said back in 2006 when the Lottery Fools got their marching orders that we were facing a six or seven year project at least, how many of you would have stopped reading there and then? But by keep saying, it’ll be finished next year, we’ve all had something to look forward to and now we’ve arrived at the point where, once the sponsons are done, and they’re well on their way, we’ll have a complete machine with only the detail work left to do so we’ll still have something to look forward too. Cool, eh?

The important thing to remember, and I am forever telling people this, is that not a single day goes by without us doing something to progress the job, even if it’s only sorting our photographs or ordering a bag of rivets. And if we keep doing that, one day we’ll wake up to discover that everything is done.

Anyway, as previously mentioned, it’s been a splendidly busy year for various reasons and there’s not been half as many updates as we ought to have turned out (though that was in part because there’s not much to write about when riveting the engine cover together) but we do try to give you good content so this time our head of ‘anal widgetry’ has penned his own account of clashing the intakes together. Once the tin-bashing was finished the rest of us went off to make sponsons and rivet the engine cover leaving Mike with a pile of painted bits that diminished with inverse proportion to his expenditure on rivets. Everyone has had a hand in the intakes but when it comes to faffing about, fannying around and generally being OCD about every detail, Mike is the man so, put your hands together and give a warm welcome to the incomparable, Micky Bullfrog!

Man, that sucks!

Mike Bull

When I joined the BBP many moons ago now the intakes were pretty much discarded under a sheet in the corner of the workshop- they’d been partly rebuilt for the dry build and then set aside while everyone got on with other things. (See recent diary, October 2012)

When the time came to pick them up again in 2010, I had the task of pulling it all out and starting the repairs on the various components. As Bill has previously explained, (and my apologies for any repetition throughout this piece) there’s quite a lot going on inside the intakes- as you might imagine with them coming from the pen of one K. Norris- so there were lots of parts that needed some care, especially considering the massive impact the intakes had suffered.

First up were the vertical bulkheads that live inside the plenum. The larger one of the two in particular was very badly damaged and ultimately needed 21 small ‘biscuit’ patches to repair it! This larger bulkhead is the next station back from the headrest, and forms the rear wall of what the original drawings call ‘the equipment bay’. We just decided it was where Donald kept his sandwiches…

Also visible here are some longitudinal stiffeners- these were part of the 1966 modifications following the intakes failure, and were added to stop the plenum walls from being able to flex outwards. They add a phenomenal amount of strength to the structure, but like everything else, they were very badly damaged and took a lot of sessions in their own right to get back to a useable condition; several of us had a few rounds on these over a long period to get them right.

Following these repairs we got on with rebuilding the formers as also detailed in previous diaries; I drew each one out on a big plywood tooling board, working from the 1954 Norris Bros. drawings, and then we had something we were able to lay the mangled formers on to for repairs.

As Bill has said, we found that what was drawn and what was built were often two different animals, and that was before things had been crashed and corroded!

Drawing things out in this manner also helped greatly in understanding the arrangement of the closing plate that the headrest cushion attaches to, and it’s other attendant pieces- there’s another piece that incorporates the canopy latch, and the piece of angle that the rear face of the canopy closes into.

All of this took some very careful interpretation to fully understand and get working, with Bill and I spending all day looking at it, only to go home and spend all night emailing about it too, all helped by Neil Sheppard and his photo archive. We’d not helped ourselves by adding our half-height bulkhead at the rear of the cockpit opening either, as this introduced a discontinuity of layers that I also had to work in so everything looked right! Here it all is seen a bit later in the process-

The green bulkhead is a permanent addition to the rear of the cockpit opening, and everything else is part of the removable intakes structure- the closing plate which holds the actual headrest cushion screws over both and brings everything back to the proper appearance. (Also of note here is the square hole in the duct roof, behind the headrest area- this was faithfully copied from the original, and is an access hole to the area underneath the radio aerial.)

It was around this time that we took a couple of shots with a helmet of the same type as Donald’s propped up in the cockpit and used it as a ‘picture of the day’- an image that a lot of people found quite poignant. Also, see the large raggedy holes in the plate at the top corners of the cushion? When the intakes first came back from repair in 1966, those holes weren’t there. Then some small, neatly drilled holes appeared. Then, these holes were roughly filed out into the form that I’ve replicated here in the new plate- clearly, there were still things going on with the intakes that were being tweaked as the runs progressed. January 4th is our snapshot- who knows how the boat may have been further tweaked on the 5th, etc?

Skipping ahead to much, much later…the formers were eventually all repaired and painted and I riveted the front edge of the duct into the front ‘spectangles’ former with a complicated system of doublers that we’d added behind the duct skin for strength. Then it was over to the lads to rivet the rest of the formers to the duct.

Then finally, new skins could be wheeled for the outsides-

These were copied form the original outer skin, which comprises two sides and a top but which came off the crashed intake structure, and remains, in one big piece-

This original outer skin, though beyond sensible reuse, was an absolute goldmine of information for the placement of fittings and rivets and so on, and was constantly referred back to.

One thing that quickly became apparent is that the lap joints in the original skins are not symmetrical– so neither are our new items. The distinctive brackets that hold the support struts for the spray deflectors are also in different places side for side- one is higher from the thrust line datum than the other, and one is nearer the lap joint in the skins than the other. The original brackets repaired beautifully, and were positioned on the new skins exactly as ‘wrong’ as they were on then original.

See the differing gap between the brackets and the joint in the skins above?

Another thing that quickly became evident from examining the original skins was that there was no common centreline through the top of the intakes where all the various fittings had been mounted. ‘Near as’ seemed to be good enough for our predecessors, so yet again to be right, we had to do it wrong- but accurately.

There are various items that live on top of the intakes- a little vent cover, a pair of steel eyelets, redundant camera mounts…then there’s the radio aerial, fuel filler flap, the old radio aerial mount, and the fuel tank breather pipe. Finally right at the back we get to the distinctive row of 2BA screws that span the back edge of the intakes, screwing into the dismountable former that encloses the fuel tank.

To go through each of these items in turn…extending up through the old redundant canopy hinge plate is a little one-inch pipe, which we presume was some kind of vent. The pipe passes from the inside of the duct, up through the hinge plate, through the outer skin on top, and has a little D-shaped cover on the outside. The original cover was beyond repair, but there was enough there to serve as a pattern for Bill to tap out a new one.

There you can see the original hinge, the new D cover, and behind it, two clusters of large rivets. As on the original skin these were offset to one side, clearly put in to fill redundant holes which we think were once used to mount a camera. I painstakingly measured the positions of these holes from the original skin to the new one- not an easy task with little in the way of reference and with the original skin also being a bit crumply- and it wasn’t until I’d committed and drilled the holes that I then realised that we still had some original little doubling plates that went on the underside. So I’d had drilling templates all along, if not positional ones! Out they came from the stores and…gulp…they lined up perfectly with my new holes! So, I must have done something right, which was a relief.

Moving back again there are two distinctive steel eyelets that poke out of the top- I’ve no idea what they were for, though they are quite substantial little things, albeit only bolted through the single layer of the outer skin. Between these lives the radio aerial, and there’s a tale in it’s own right…the original was sheared off in the accident and will still be at the bottom of Coniston somewhere, and we’ve scoured the world to try and find out what it was and where it came from, but at the time of writing we have still to ID the thing. It seems to have first appeared while the boat was in Australia, and looks more civilian than military, but whatever it was, we’re going to have to replicate it. Luckily, with it sitting next to the steel eyelets and with us having some high resolution pictures of it, it’s no drama to scale it into a working drawing to have one replicated. It would still be nice to find a real one though…

Going aft again we get to the fuel filler flap, which entailed me copying a distorted D shaped opening with no datums over to the new skin, while ensuring that the couple of original parts we had from it still fitted! I was on my own with the boat that afternoon, and was glad no one was there watching when I started to cut a 6 inch hole in our lovely new intake skin…

Behind this and right at the back we get to the old radio aerial mount, which we call ‘the nipple’. After a couple of goes at scaling it this was replicated in aluminium. Next to this lived a breather pipe for the fuel tank, which was easily positioned as the cut out for it still existed in the original doubling band that lives under the back edge of the intakes.

This band rivets to the back edge of the intakes, and extends back to take the springs for the Dzus screw fasteners that hold down the front edge of the engine cover. The screws for the dismountable former also pass through it, so we could drill back through these holes and place those with absolute accuracy. Of course, every single hole in the former needed a new captive nut riveting in to take the screws…

So, that was the detailing along the top; all minor things, yet each one as important as anything else in terms of making the boat ‘right’- it’s imperative that she’s still as Donald last knew her, however small the detail. For example- the bodywork on Bluebird was so heavily filled and so thick with layers of blue paint that the lap joints in the skins along the intakes, engine and tail covers were all but invisible. Once the intakes were rebuilt in 1966, however, you can clearly see the lap joint as there was now only one thin layer of (the wrong!) blue paint on top of the bare metal. Plus, the screws around the back were unpainted when the intakes returned to Coniston- though later on, they’ve been touched up. The little fuel tank breather pipe points either forwards or aft depending on when the photo was taken- on January 4th 1967, it happened to be facing aft. Detail, details!

So, we’ve got new skins, fully detailed, and the next job was to recreate the closing strips that run down the sides of the intakes (and the whole boat, in fact) to bridge the gap between the upper works and the main hull. These come in three pieces for each side and the original ones from the intakes were in a dreadful state, so once again could only serve as patterns for some new ones.

Clearly these strips were supposed to be four inches wide, but in practice they were anything but, varying under and over that measurement along the length of the boat. Typical! Made of 2mm aluminium with chamfered rear faces so they sit into the joggles in the panels above and below, the strips are quite substantial pieces in their own right. On the right hand example lives an original mooring eye, which we shall leave in the original paint when the boat is finished.

Finally, we can get to actually building the intakes up for good! Bill and I started this together, the first job being to rivet the plenum walls into the duct. Now, imagine covering all the edges of a really awkward shape with a thick brown glutinous substance that is utterly unforgiving of being gotten on, well, anything, and THEN try and load that big awkward shape up the back of a narrow metal tunnel!

Yeah, we got messy.

Once the walls were in they were followed by the bulkheads and stiffeners that live inside it, built in turn as each bay then closed out the one behind it. This is the rear bulkhead and the first lot of stiffeners, and you can see that there’s very little green going on here. (The duct itself is also new of course, but was painted blue just to make our lives easier for once)

All these joins were subsequently very heavily glooped up with further marine sealants, before the next bulkhead went in.