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Colonial Diaspora

Stub axles 

Thursday, July 23, 2009 11:37:30 AM Categories: engineering problems
One bad week for diamond-frames, one good week for recumbent builders. I have been to the Dump, and there must have been forty bike frames and their concomitant bits and pieces cast aside by the unworthy souls who once possessed them. I confiscated a tiny BMX frame which appeared to have relatively sound front forks, an Australian racing bike of ghastly mien with 27 inch wheels which I was delighted subsequently to find weighed in at 22.5 lbs, and eight wheels. The racing bike was branded Ricardo, of which I have never heard, but it has a frame sporting a seamless chromoly sticker and anyway with a name like that my ego was unable to resist it. Among the wheels was a crippled Campag 700c with an aero rim which reverence forced me to save, and which, duly straightened and fitted with a widened rear hub has the potential to become a stiff rear wheel for a trike or something that I haven't yet thought of. And I also found what I was really looking for, which was a rubbishy old MTB front wheel with a fat alloy hub.
 

If alloy hubs are big enough, and this sometimes applies to MTB hubs, you can unbuild them and knock the cups out and then machine 28mm recesses into the sides and fit 6001 bearings. If there's sufficient meat to bore at least a 16mm hole through the middle for a spacer it allows for 12mm stub axles, which are useful in so many applications from trikes to trailers that I need not rehearse them. Had I done my sums and measured everything beforehand I would have chickened out because when you've machined these recesses you find there's precious little metal inside of the flange, but one of my trikes, which has just such front wheels, has been around for 3,000 miles and this gives me confidence.

Elderly wheels from the Dump have to be dismantled with care in New Zealand. You'd be amazed at how many 700c 4-cross wheels there are until you sneak onto the WISIL site http://www.wisil.recumbents.com/wisil/spokes!.asp and discover that the spoke length is that of redundant 27 inch 3-cross wheels. At tenpence each (we cheapskates always used galvanized) and with  - erm - several machines then a stash of spare spokes is a sound investment.

Unfortunately it sometimes rains here - 'tis doing right now - and rain + wheels = chemical welding. When the spoke key really won't turn, a single drop of diesel oil on the outer end and then ten seconds of small propane flame applied to the nipple, is generally enough to make the oil bubble and seep into the thread whereupon the spoke concedes defeat.
 
 
Removing the axle and cups is straightforward but locating the hub in the 3-jaw isn't. It is an axiom of Clive Sleath and W.C.O. Pettingill and everyone else with a lathe that if you take something out of a chuck and reverse it, the other end is guaranteed to be out of true. Guaranteed. And if you just nip the flanges, which is all there is to nip in hubbery, then even the 4-jaw is useless because the bit you can clock won't resemble the bit that you're about to machine. The problem is alleviated with a steady, but even so the trick is to machine the other end's recess slightly over-sized, and glue the bearings in with Loctite 660. When nipped with the bolt, the theory is the bearings find one another's parallelism.

Oh, and Mr and Mrs Loctite, since I've just very generously given you a gratuitous advert, don't let me discourage you from sending any free samples you care to pass my way.

Holidays 

Sunday, July 19, 2009 9:12:16 AM Categories: New Zealand
 
No work on Sam's trike for a week because we have been on hols in a town called Wanaka; 1,000 kms to get there and 1,000 kms to get home which added 400 kilograms of carbon dioxide to the atmosphere and which I'm 'fraid is one of the reasons why every climate scientist on the planet (other than those half-dozen retained by Exxon) is in a tizz with the world's politicians. The latter seem mesmerised by the world's economists who despite the year's revelations earnestly continue to tell us that you can have Economic Growth forever. Or that the economy is a perpetual motion machine. Or something.
 
Everything you need to know about Wanaka is contained in the two words 'no bookshop'. There are four ski shops and five tourist shops and a million holiday homes and a supermarket that is empty until the ski fields close whereafter it is jammed with approximately equal numbers of young adults and security staff.
 
 
We have been skiing. My wife, that is, and the children. I have yet to grasp the attraction of standing on two planks of wood at the top of a slippery mountain and accelerating downwards at +/- 16.08 feet per second per second (depending on slope) with no brakes whatever. The latest fashion is snow-boarding, Sam the Scotchman assures me, which is to stand on a single plank about the size of a wardrobe door, which must even further limit one's prospect of a controlled stop. One cannot apply excess toe-in balanced on a door.
 
I did not ski, but rather cycled and on Monday a Spitfire pilot put on an aerial display for me and on Wednesday there was a rather agreeable earthquake which for a minute made the cottage sway as if it were a small dinghy splashing around in the surf, and on Friday I found a Historic Site on the Cardrona road. There are brown road signs in New Zealand that say Historic Site on them and when you're on a bike you stop and have a look, and on this occasion I found that Robert Studholme tended a tree nursery opposite here. It was established in 1879 and the last trees were felled about 1960. (I like history. I was so excited I copied it down.)
 

Now because you happen to know that I am a persistent liar you are going to say that I am fibbing on all three counts but the first two are on Ye Olde Internette so they must be true
and the last one isn't so you'll just have to cycle up the Cardrona road yourself and see.

 
The kettle in the cottage, if this is of interest, was a Breville Model SK60B and it leaked so badly that the base stood on a folded towel. The base bore the printed message Please note that some condensed moisture may gather on the base after the kettle has boiled. This is part of the normal workings of the kettle and does not indicate a fault with the product. (I copied it carefully, you may depend.) As the children, weeping with laughter said, 'Yeah, right.'
 
 
On the way there we stayed with Mr Knight and he took us to a secret place he has researched where 14 steam engines were tipped into a river bank to stop the water undermining the railway and I'm not going to tell you where it is because I'm cruel, and on the way back we also stopped with Mr Knight where my children asked his children to say 'Ni' whereupon they told them that they were the Knights who say Ni which caused much delight among the cognoscenti and total bafflement to everyone else.
 
Old steam engines, somewhere in New Zealand
 
 
Mr Knight guided us through the mysteries of the Tour because he has a television and knows what's going on and we don't, and I admired his latest Italian racer, a fully-Campag equipped Coppi, and I am forbidden to broadcast how many bicycles he now owns for fear of alerting his wife. All his bicycles are pristine concours specimens and all of them are red, so he occasionally smuggles new ones in when she isn't paying attention. Mrs Knight told us of the struggles she has learning Maori, where one Maori teacher instructs exact pronunciation and a Maori teacher from another iwi (iwi = 'tribe') disputes the pronunciation telling her there's no point learning it if you get the pronunciation wrong which I fear had us all saying 'Yeah, right' again. One might start by inviting the two Maori teachers to travel to England and ask natives of, say, Newcastle-on-Tyne, Huddersfield, King's Lynn and Brixton to pronounce - well, anything at all actually - and then discuss which is 'correct' English. Funnily enough I have found several copies of Simeon Potter's Our Language in New Zealand bookshops whereas I never found a single copy in England.

Right, must try to get back on topic to keep the BHPV Editorial Police at bay.

Munted track rod ends 

Tuesday, July 7, 2009 10:44:04 AM Categories: engineering problems
Munting is a verb. - Have we discussed this? - I munt, you munt, he she or it munts. Munto, muntas, muntat as Nellie would have it. Nellie stood in front of a blackboard when I was eleven and waved - well, flapped - her arms about and largely failed to teach me Latin. Latin was not my forte. Burning holes in Mitchell's satchell was my forte. Mitchell sat in front of me - Middleton, Mitchell - it was that sort of school - and a couple of minutes was all that was required with a modest lens such as you might find in your blazer pocket to get the pleasant fumes of burning leather into the atmosphere, and when that palled, it was even quicker to get Mitchell to jump off his chair when the lens was focussed on his ankle. (You had to burn through his sock to get at his ankle.) This wasn't Mitchell who became a judge. This was the other Mitchell, David Mitchell, whose fate (other than having a perforated ankle) remains unknown, at least to me. Mitchell who became a judge became a judge - we sort of deduced that - and forgets my birthday even though he ceaselessly reminds me that his is the 1st of May.

But munting is a New Zealand verb, and a jolly useful one too. I don't know how I managed all these years in a workshop without recourse to it. Yesterday I munted my hand, and it bled all over the place.




You can only do so much in rebuilding a munted trike frame without removing ucky oily bits with only your fingers and thumbs pincing together and all your other fingers sticking delicately out in the manner used when having tea with the Queen. (Of course I know about these things. Whenever Her Majesty phones me it is to ask when I'm coming back.) When I came to pull bits off Sam's trike, wondering why he hadn't cleaned all the ucky oily bits for me, a Horrid Revelation occurred. Lots of us have used track rod ends as the bearings for bicycle kingpins starting with faux Dursley Pedersens and ending with recumbent trikes. We normally put the thing together, ride, and forget about the bearings reassuring ourselves that any resultant floppiness is normal wear.
 
 
How wrong we are.

Off came the right wheel on its stub axle, and one of the track-rod-end-kingpin-bearings was all loose and rattly. I examined it. At once it was apparent that the bronze ring on one side was raised. Only on the top side, of course. If you twist the spherical bit you can see that within the bearing there is a division between the top retaining bronze ring and the bottom, so applying a constant jolting force, such as is provided by roads, is going to knock one of these bronze retaining rings out of where it's been mechanically peened in place. Here's a pretty drawing:

So what to do becomes a Big Problem, because replacing it with another track rod end is - well, you know what it is. Track rod ends need to be kept for track rods and not used for nefarious purposes like kingpins

And therefore Sam is going to have to wait for me to make totally new new kingpins and stub axles, dammit. And since Susie munted her window this morning, he's going to have to wait even longer.

 

Balanced Forces 

Monday, June 29, 2009 12:17:32 PM Categories: Bob Knight's fairing mooning
Behold, I have sinned. I have not worked all morning. My friend Susan is sitting huddled in Clapham fondly imagining I am busy working on half a book with her and in fact I am not doing half a book at all. I am busy making a cabinet. Two cabinets, actually. These cabinets are not specifically because I need cabinets; rather, they are because I am supposed to be doing Chapter 2 and in fact I suffer from a dreadful affliction which is to say whenever there is a pressing deadline (though can Chapter 2 be pressing?) I indulge in Workshop Tidying. This is an affliction specific to me. Nobody else in the world suffers from it. Faced with a difficult drawing I will spend two hours sharpening every pencil I possess and then I will hoover the room even under my glass draughting table and - mark this - behind the computer. Amazing how much fluff a computer generates. If the world abandoned computers there'd be a fluff shortage.
 
Faced with Chapter 2, I immediately note that the four drawers and broken cupboard that Dr Brewer didn't want and very kindly gave me have been sitting idle in the sheds for a month, so naturally now is the time to fetch out the glue and screws and saws and convert them into useful storage space for the lathe chucks which have been sitting bathed in unholy swarf these four years past on the floor where lathe chucks have no business to be, and I am not going to offer a photograph of the resultant cabinets because I happen to know for a fact that Nigel Farrell, whose exploits have been hitherto detailed here, is a cabinet maker and I don't want him laughing at me. His wife's called Annaliisa, by the way. One of us can't spell.
 
 
Anyway, my steel has arrived so I have few excuses to make cabinets and ought to be busy rebuilding Sam the Scotchman's trike frame as my chief displacement activity. (I call him a Scotchman because I happen to know for another fact that they hate being called that.)(Everyone knows that.)(Uh?)(So why did I tell you?)
 
Unfortunately John is studying Balanced Forces so further work on trikes/cabinets/Chapter 2 has to be postponed while we deal with this, because harrassed schoolmistresses cannot explain Balanced Forces to thirty fourteen-year-olds in forty minutes with even the remotest chances of success. Luckily his memory of Mr Knight zooming round and round at 50 kph for an hour is fresh, so we focus on
 
a) how much air weighs (.88 kg per cubic metre, from memory) 
b) how much of it you scoop up in your arms when you pedal through it 
c) pedalling twice as fast means you scoop up twice the mass in the same time 
d) and that you have to accelerate all that extra air not only to how fast you were going, but to how fast you are now going 
e) if you can just nudge it aside, diagonally, instead of scooping it up in your arms, then you can go faster 
f) which is what Bob's fairing was all about 
g) and that when you start off your forces aren't balanced which is why you accelerate
h) and that when your forces balance you stop accelerating
i) which is why Bob couldn't go faster than 50 KPH.

This is a lot to take in, so we move on to what forces apply when a 22 year old stands on top of a car with his trousers round his ankles http://forums.gumtree.com/topic228071.html and the car suddenly stops. The 22 year old has velocity, but no force. Accordingly he continues forwards at his constant 80 kph, until his face encounters a force. The force grinds his face off, and as he is not pedalling or running to perpetuate his velocity, he undergoes negative acceleration. John enjoys this greatly. Whenever the concept becomes difficult, we add lurid detail. It is a topic of considerable interest because it so happened that John and I were driving down to stay with Bob Knight on the morning this unusual incident took place, and were held up for half an hour at the Lewis Pass watching the rescue helicopter. The fireman told us 'not a pretty sight' but when we were allowed past John reported that he saw a body lying in the road but no crashed car, which mystery was only solved as the news reports came through. The 22 year old gentleman concerned is now, I gather, on my mate's mechanical engineering course, where he exhibits a Police ankle bracelet, half a face, a surprising amount of conceit at his fame, and occasional absences for further reconstructive chirurgery.

My mate (in the Australian sense, not the animal pairing sense) is the Editor of the New Zealand HPV Newsletter, and shares with Dr Lowing a misplaced enthusiasm for those front wheel drive bikes where the bottom bracket is allowed to waggle about along with the handlebars and front forks. He's just bought a lathe, and needs to know how to work it. My (Australian) mate, that is, not old Lowing. Lowing needs to get on with his dissertation on Intellectual Law. And I need to get on with Chapter 2. And the mooning young man on top of the car needs to grow a new head, this time with a brain in it.

Broken trike 

Saturday, June 20, 2009 12:05:43 PM Categories: engineering problems
A broken trike, yesterday


Came a phone call this morning. It was Sam. I knew it was Sam because I could only understand one in twenty of the words uttered: Sam is a Scotsman, Scottish, from Scotlnad and very probably wears the McEachern Tartan but very probably doesn't wear it sitting next to the Queen and you very probably can't google Images of him sitting there. - Not that I am in any way suggesting anyone should google Images and try to find pictures of kilted Sctosmen sitting next to the Queen. Why can't I spell Scotlnad? Or Sctosmen?
 
Sam's trike had broken. We need a discussion of aluminium and whether it is ever a suitable material for making recumbent trikes out of, and I imagine this discussion will become very heated because it's a bit like being able to spell Scotsmen. There are people who can spell Aluminium. There are also Americans. - And in passing, there is a worrying tendency for the smart young journalists who people the airwaves here to adopt Americanisms and I have heard 'nine through five' as if there were sentient beings who might tolerate such a phrase, and I have also heard 'A through Zee' and if I hear it again I will actually kill myself. My American friends sometimes ask me why the Arab world hates them and in fact it is because they say Missile as if it were a Catholic devotional service book and the Arabs - well, the devout ones - are all worried lest that is what America is aiming at them. If they knew it was only Missiles they wouldn't be nearly so bothered. Arabs are accustomed to Missiles. - D'you know, I think I ought to get back On Topic lest someone sidle up to me with a rucksac on and someone else blow an entirely innocent bus queue to bits in a deeply committed act of incomprehensible self-sacrifice.

Sam's trike was built locally by a friend of both of us and it handled superbly. But it was made of aluminium. And it sort of - well - snapped. It would not be the first aluminium frame I have seen that snapped. I imagine it is not an entirely unfamiliar theme to anyone in the BHPC. But there is this myth about aluminium and light weight which since aluminium is about three times as light as steel is understandable, but it is also three times less stiff than steel and sometimes basic arithmetic tells us stuff that - well anyway I'm not here to do a sermon because someone might sidle up to me with a rucksac on.

Sam's trike had broken with Sam's companion on board and she hadn't enjoyed it and I have a MIG welder. You can weld aluminium with a mig welder (clue: argon) but only if it's powerful enough and mine isn't - I've tried - so the conversation revolved around using all the trike's expensive components on a steel replacement frame; or building a back-to-back tandem trike; or building a tandem Periscope idea thing that I've nicked off Marec Hase. (We saw two of these when first we came to New Zealand, each being ridden by a German, each with a baby German on the front.) We all like the idea of being able to talk to one another on rides, and a disadvantage here on long empty roads is that if you ride side-by-side, there are people who feel compelled to drive an inch from your handlebars and hoot furiously because they aren't aware that this is legal. Something tells them it isn't. And simultaneously tells them that they are temporarily appointed Guardians of the Highway with especial responsibility for Cyclist Discipline (Single File Only).

Marec Hase's Periscope. Pino, probably, this one.


Either idea - back-to-back or Periscope - allows for conversation. A 'conventional' recumbent tandem couple encountered in Murwillumbah (there is such a place, but it is in Australia) declared that they needed headphones to be heard. I cannot go into whether or not there was any benefit in their hearing one another because I already have Scotland America and the entire Middle East after my blood - oh, okay then - nothing ever said by an Australian was ever worth hearing. But you already knew that. It's why Sherri's voice is so enormous. - er - where were we? -

Sam had also brought with him his Rebel trike, a machine built here and a whisker under a metre wide which is probably to do with New Zealand laws about what does and doesn't constitute a 'bicycle'. (You aren't allowed a sidecar on a bicycle. I would love to research the rationale for such a law.) But we tried putting two small child's chairs next to one another in front of it and found that a recumbent sociable trike a metre wide would be very sociable indeed, and should Her Majesty come over and choose to ride with Sam in his native garb, he would need to keep a very careful eye on the wind direction.

Sam has some experience of sitting on tandems, though not yet with the Queen, and said we'd need strong wheels and strong bottom bracket axles. And I, by inference, started to get all worried about whether 12mm stub axles and 36-spoke 406 wheels are up to a recumbent back-to-back tandem. I fancy they might not be, but in my case N = 0 and I fancy statistically one might with advantage require a greater sample to make a decision.

Rain Bike 

Friday, June 12, 2009 11:57:38 PM Categories: Chain case
It is raining. It rained yesterday, and the day before that, and before that; indeed it has rained for forty days and forty nights. Certainly feels like it. Had Noah gone into his garden to pick up fallen grapefruits - I'm extrapolating - he'd have worn wellies because the water would have oozed out of the soil over the top of his toes.
 
Accordingly I have not been riding my recumbents because they are all wusses. (I believe that is the term. One endeavours to keep up-to-date with these neologisms, though one can hardly claim that 'wuss' is a particularly refulgent term. - Refulgent - now there's a word that shouldn't be allowed to fall into desuetude.) - My recumbents don't like rain because they each possess 150 inches of chain and I am one of those glorious obsessives who boil up chains in candlewax because oil + road dust = lapping compound. Because I am obsessive at least one of my waxed chains has 4,000 miles on it and no measureable wear. But candlewax isn't very good at rain repulsion, is the truth, and waxing chains is  - well - you insert an appropriate neologism.
 
To effect the purchase of two litres of milk I have been riding my Rain Bike. Milk deliveries here ceased when Corporate Executives learnt it was cheaper to have millions of plastic two-litre milk containers bobbing up and down  in the middle of the Pacific Gyre than to wash and re-use glass milk bottles. This is called Progress, which Corporate Executives assure us you can't stop. Among car drivers glass bottles remain de rigeur for beer, and after contentedly swigging most of the beer they cast the bottles out of their passenger windows where they turn into punctures. Once I saw a drunken possum, sitting happily at the side of the road licking his paws next to an unbroken beer bottle. He was most comical. We're supposed to kill possums but I can't ever persuade myself to. It'd be like killing a teddy bear. I daresay your average New Zealander would classify me as a wuss.
 
To buy milk I have to cycle into Motueka and this involves 8 glorious miles up the west bank of the Motueka River and 7 glorious miles back along the other side to Motueka town, and then 2 rather inglorious urban miles, dodging shattered brown glass, back over the Motueka Bridge. The Bridge is actually only a quarter of a mile from our house and one could nip in and out in half an hour if the Motueka Valley wasn't so lovely to ride. - One could probably obtain the milk for nothing if one could cycle with a pail because there are cows all over the place, each producing (according to a new report by Fonterra, a NZ company that trades in milk) 0.94 kg of carbon dioxide equivalents per kg of liquid milk. - Exam question: Discuss the morality of not being a vegan. -
 
My rain bike came off the Dump and cost me $40 which is sixteen pounds in civilised coinage. I bought it for the bits because it has drum Sachs brakes front and rear and I also bought a Raleigh Sports - also a lady's model and also for $40 - because that had Sturmey Archer drum brakes front and rear, but then I noticed that both were intact except for air in their tyres and moreover both of them had chain cases. And on the back of their mudguards there were little stickers that said 'Kersten Tweewielers' and 'Van Megen Tweewielers Willemsweg 98 Tel. 565224 Nijmegen' and I had to keep them exactly as they were to remind me of going Abroad to the Continong where people made exotic sounds with their mouths that sounded very like speech but couldn't have been because it wasn't English, and where there were fabulous little cafes where you could sit and drink cold lager that tasted Foreign and you could buy schnitzel that tasted superb until someone told you how veal is reared. - Exam question: Discuss the morality etc. and we're back to milk production again.
 
The Dump had these two ladies' bikes, one large and one small, and each had 3 hub gears which are fine for the Motueka valley road which is flat but must have been taxing to a pair of Dutch lesbians who emigrated from the flat lands of Holland, I deduce, to the hilly country of New Zealand. Because otherwise they wouldn't have taken them to the Dump.


 
My Rain Bike

Anyway now I have two bicycles that don't get their chains waxed. They get liberally soused in oil. And the oil picks up no abrasive road dust because the chains are inside these cases and my trouser-legs pick up no oil, actually because they're safely tucked up inside my wellies when I ride my Rain Bike, and my wife rides her Rain Bike to Motueka secure in the knowledge that nobody'll nick it from outside the surgery because what fifteen-year-old would want a Raleigh Sport with three gears and drum brakes and a chaincase?
 
However, you are right. That is, actually, the uncomfortablest saddle in the entire world.
 
I just wish I was as clever as Clemens Bucher.
 

Clemens Bucher's Rain Bike, nicked from http://www.liegerad-berlin.de/wir/clemens/

Wheel discs 

Saturday, June 6, 2009 9:49:32 AM Categories: wheel discs

In between discussing how best to transport his stone otter collection on moving house, Clive Sleath once told me that he used foam for wheel discs. We will not enter into a discussion of Clive Sleath's sanity - this is the Internet, after all, where innocent children roam - but it always struck me that foam would be an excellent wheel disc and so it proved until I left a bike leaning against a pleasant wayside oak in the sun and the air inside all the little closed cells expanded and the foam became all mountainous and started rubbing against various frame parts and whatnot.

Corriboard is the stuff for wheel discs: like foam it is free: all you need is some pre-loved estate agents' signs. - The signs are pre-loved, not the estate agents. We will not enter into a discussion of estate agents etc etc etc though they don't collect stone otters as far as I'm aware, nor three-foot model hydroplanes a small steam traction engine a home-made milling machine a very small wind-tunnel and three lathes. (Quite an interesting place, was Clive Sleath's garage.) 3mm thick corriboard is good for 406 wheels, though you might manage 4mm thick for the flat side of a dished 700c rear wheel and not need to cut out a slice of cake. (This may become clearer later, depending on how eloquent I'm feeling this morning.)


My pre-loved estate agents' signs have bullet holes in them. These are real bullet holes and not those foolish stick-on things that adorn Saunders' wife's car (whatever for? Conversation starter? 'I see you have cheap imitation bullet-hole stickers amusingly placed on your car. Why, pray? Do tell') and I know they're real because I stole them off the rifle range, where some keen-eyed lad had arrived to sight in his rifle and then discovered he had nothing to shoot at. Apparently this is very common. Ross Fitzsimmons, who is a keen rifleman, once told me that 'you're not a real hunter until you get to the hut and find you've forgotten the bolt of your rifle.' (Apologies to all English people reading this, since I'm aware that everyone in England now eschews such things as rifles. Which fact pleases me inordinately because they're all out there busily buying A Certain Book to read up on catapults, bless them.) - Along comes a hunter in his Ute and unloads all his shooting gear. Hunters all have Utes. Wild animals are going to be perfectly safe when the oil crisis comes, because hunters cannot function without a Ute. - It is an Australian word, and means Large Bulbous Ugly Japanese Pick-up Truck. - Anyway then he finds he hasn't got a target, so back down the road, shortly to reappear with an estate agent's sign. He expresses his love for this sign with his rifle, and then drives off again leaving the sign several Coke cans and a fag packet, and all his empty cartridges which I pick up and carry off home so that John can indulge in Trench Art. You can still buy solder in New Zealand.
 

Early Learning Centre Buyers have thus far not made John any approaches. In passing, his violin teacher is puzzlingly optimistic if she imagines he is going to practice that atonal A Thomas piece she gave him last week. It's horrible. Really, truly horrible. I have this theory about why A Thomas isn't as famous as Bach, but we won't go into it right now.

 
Okay: what you need is Apparatus, and the special thing for wheeldisc making is a stick with a nail in it. More elegant tools have been made, some by chimpanzees, but a stick with a nail is all you need for corriboard. For a 406 wheel, drill another hole 198.5mm from the nail and into it screw one of those square-headed screws that are all the rage with house builders. File the tip of this screw so that it's as sharp as a scalpel. Whack the nail right through the stick, and screw the scalpel far enough to protrude 2mm. Spread the estate agent sign on the carpet, bonk the nail through it where you propose the middle of the disc will be, and if the scalpel-screw is sharp enough, it cuts a perfect circle in one quick sweep. Try cutting it with scissors and it'll take half an hour and still be a bit wonky.



I always try cutting the middle hole in the same way - same diameter as the centre of the hub, natch - but it never works and I always resort to a Dremel. Next, pair of scissors, and cut a radius across the diagonal of the corriboard grain. This theoretically prevents buckling. Then cut out a 'slice of cake' to turn the thing into a cone. You cut another radius about 3/4 of an inch away - I did measure this, and cunningly wrote it on a bit of paper but I mislaid it because I am incompetent, and it was either 18 or 23 mm (can't remember which) at the circumference - and tug the two edges together to make your cone. Fix with duck tape. Do not spell this duct tape, which is wrong. You don't get duct cotton. (I state this to annoy all who hold the contrary view.)

Now apply to the wheel, and using a Phillips screwdriver whack in nine equidistant holes about an inch in from the circumference, and use 6mm nylon nuts and bolts to hold it to the identical wheel disc on t'other side. And then all you need to finish the job is to apply a bandage to your hand where you impaled it making the matching holes. A minor irritant is having to undo all the nylon bolts looking for the valve. Cleverly made holes and flaps always fail and eventually make click-click-click noises. Another minor irritant is trying to cut out a hole in the corriboard to get your wheel magnet close enough to the sensor for the computer to work. Another minor irritant is that it does, actually, slightly swell in the sun. Another minor irritant is that I keep increasing the number of minor irritants, wherefore I shall now stop.

Kettles 

Friday, June 5, 2009 11:39:11 AM Categories: engineering problems
This morning it was Very Cold which I'm aware is a difficult concept on a hot June morning in Coalbrookdale and Ruislip, but icicles stood as stalagmites under the dripping garden taps in Riwaka and our kettle stood in a flood of water on the kitchen bench. Our kettle is a Breville Platinum Model SK50S, Engineered in Australia by Breville Manufactured in China to Our Exact Specifications, all of which I'm sure Breville are happy and contented for you to know because they stamped it on its base. The puddle of water it stood in had leaked out from a small crack which I am equally sure Breville do not want you to know, though they don't need to write it on the base because after a while you'll spot it for yourself. Are Breville a bunch of marketing idiots? Are they in fact some kind of subdivision of the Black and Decker Stupid Design Dept.? What goes through the corporate executive's mind of when its Board of Directors decides to employ an Engineer to Exactly Specify how to make a kettle? Have kettles not been made, with some success, in the past? What exactly is lacking in prior kettle design that requires Australian Engineers to add their tuppeny ha'p'orth of Specification to be dictated to a kettle factory somewhere in China? Is the Modern Kitchen Occupant no longer able to function a kettle without a transparent section at the side to facilitate the assessment of how full it might be? Can't we just take the *ucking lid off? And given the likely differential expansion of plastic and stainless steel, what kind of engineer would specify their juxtaposition in a container that has - let us remind Breville - as its primary aims both to be water-tight and to vary its temperature from 0 degrees to 100 degrees? Note to the Membership: do not buy a Breville kettle. They're crap.

 
All of which could be a perfectly innocent rant but for the fact that it reminds us of one of the sadly late Steve Donaldson's favourite principles: Keep It Simple, Stupid. And this leads me back to the subject in hand. Some years ago a chap called Rob Wallace built a machine called Red October, still extant and owned by Paul Dunlop, but finding that it was (in the pithy words, I think, of gNick) 'like wrestling with a gorilla in a sauna' and not conducive to mild commuting, it sort of got retired.


One of these is Red October

Therefore I am now going to focus on wheel discs which can be had for free and which provide a small advantage over spokes if you get um design right. This fairings game is all very well while you're making one, but, face-a-fact (as my Hungarian father-in-law merrily said), a wheel disc is altogether less stressful. And wheeldiscs, too, can be made of corriboard.

Tomorrow, cried Toad.

NZ Hour Record 

Monday, June 1, 2009 10:59:13 AM Categories: Bob Knight's fairing Correx corriboard corflute fairing
 
L to R - Nigel Farrell's left leg; an exceptionally handsome gifted intelligent wonderful kindly warm generous noble human whom modesty forbids me to name, and three quarters of Aarn Tate. - Oh, and Nigel's (bomb doors open) and Bob's corriboard faired machines, frontal view, prior to battle.


 

Okay, here as promised are the Results.

Bob Knight: 50.7272 kilometres. New NZ Hour Record.
 
Unf. at the exact moment (literally) Bob had established this new Record, Nigel had broken it. Much rejoicing in the NZ camp; chiz in the Brit camp.

Nigel Farrell: 52.6643 kilometres. Newer NZ Hour Record

We were able to determine the distance to the fourth decimal point because we had a team of scientists armed with Vernier callipers and synchronised stopwatches lying about the track and we were able to confirm it divinely because we had a cell-phone call from Thou who knowest their downsitting and uprising and spiest out all their ways (Ps 139, from memory needless to add, and not a very good memory, even more needless to add.). And if you disbelieve me, you horrid sceptics, it's on the Internet http://www.kiwihpv.org.nz/photos_hour_record.html so it has to be true even though the reporter was lying about the fibreglass.
 

Okay.

So what actually happened was this. Annalisa Farrell and I sat down in a small and cold huddle on some foam I had the Great Presence of Mind to Bring With Me (so nur to you Dr Lowing) and discussed how hard our respective hearts were beating. And, honi soit qui mal y pense, this was not some kind of illicit amorous tryst; this is just what happens when you've spent months discussing and worrying with someone about an attempt like this and you know 'zackly how much work, how many hours, how much tension, how much pressure, has gone into it. And I'm not even married to Nigel Farrell. (The attentive reader will already have presumed this but there is a certain school of thought in the BHPC that I am Bonkers in the Nut and I just wish to scotch any further imaginative allegations before they are made, Mr Larrington.) Moreover John, a son of mine who was timekeeping too, told me afterwards that his heart was pounding. I think everyone's was. That Nigel's and Bob's were goes without saying though I see I have rather pointlessly just said it.
 
Away they both went, the threatened icy weather holding off and the air reasonably still. Annalisa, who we have established is a pretty serious competitive cyclist and knows what she's talking about, voiced worries about Nigel going too fast too early; I voiced worries about Bob crashing an untested machine in which he had had precisely 54 minutes' riding experience. (That was Saturday.) But it was looking well even though he was taking a wide line, and I knew without his confirming it to me afterwards that this wide line was largely to do with not knowing what the bally thing was likely to do at any point. (In fact his computer told us afterwards it had done an additional 1.5 km which indicates how far outside the line he was riding. Which distance of course cannot count in a record, because all machines waver outside the line.)

 
For the first fifteen minutes there was a very, very slow creep as Bob closed the gap. There was very little in it, maybe an eighth of a lap, but at one point Bob could just see Nigel coming off the straight ahead of him.
 

We now need a Technical Digression, because I had privily asked Geoff Bird for any comments he might have about the fairing and he had replied that the only thing he could see was the prospect of Bob's windscreen misting up, it being very close to his face. Now this is an evil for which I regret I must take responsibility, because I had recommended that the closer the screen was to the eyes the better, for visibility's sake. Both Bob and I are motorcyclists (what a dreadful admission. But it's true) and we weren't too worried about this: applications of neat washing up liquid on the inside usually prevent misting of a motorcycle helmet's visor. What we hadn't banked on was the fact that when you ride a motorbike you aren't pedalling hard. (Shall we take Humorous Moped comments as read?) So during Saturday's trials when it became apparent that misting up was a very big problem, Nigel offered his cordless drill and together we all cut a slit at the base of the windscreen and this reduced the misting to the point where Bob thought he could probably see okay.

 
However - reverting to the Record Attempt - the misting gradually started to increase, and with the already dodgy handling of the Ratracer's new tiller steering and the slightly dodgy corners of the track, being able to see exactly where he was going was becoming more and more of an issue. And at this point Nigel, with the confidence of years of riding his machine and even riding it on open roads in time trial events with some slightly-more-tolerant-club-members-than-the-UCI-might-like, started to increase his own pace. Moreover Nigel had no screen, and with an obviously better handling machine was able to close in harder on the innermost racing line. So from about half-way through the hour, the gap reversed and Nigel started to close in on Bob. Exactly when he lapped (actually, half-lapped him; they started on opposite sides of course) him I didn't note, but it was quite late on in the piece.

 
And then in the 85th lap disaster, of a thankfully mild sort, struck. We felt it in the stands: a sudden blast of cold wind. You could see Bob's racing line start to waver: he was fighting to keep it on the track, and those of us who saw what happened to him at Leicester will have no difficulty knowing what was going on in his mind. - Afterwards he was to tell me it was the most terrifying experience of his entire life. - He felt he had no idea at all whether the thing was going to fall, whether he could hold it upright, whether he would crash, and almost worst of all to an HPV combatant, whether he would get in the way of his deadly (1) foe's attempt. There were about ten minutes to go, and for the whole of that time you could see Bob's machine slowing in every corner, and see him trying to accelerate to pick up the lost speed in the all-too-short straights. And - since we're all physicists and know that F=MA - you know how this acceleration takes it out of you. And from then on, Nigel started lapping him regularly - well, four times of course - and had, unfortunately, to do so on the outside of the track because Bob was sticking as close to the middle as he dared so that if the now badly gusting wind took him out, he would go onto grass and not into the hard wall around the outside of the track and perhaps spin into Nigel's way. You could see the worry in Annalisa's face. She wasn't worried for her husband - he seemed in complete control of his bike despite the wind - she was watching, with cheeks drawn and teeth clamped anxiously together, to see if Bob's Ratracer was going to fall. And at one point when it looked as if he might actually stop and withdraw, both Annalisa and I were on our feet yelling at him to keep going, because we could see he was within grasp of breaking the existing Record. I had never thought I could be so agitated as a spectator. It was horrible.

But, in the end, it was over. And, most important of all, he hadn't crashed, hadn't lost any more than a bit of skin from his knees - the fairing was too tight - and by truly miraculous courage had actually broken the existing NZ Hour Record. I trotted alongside to catch him, we lifted the cover, he flopped out and performed a creditable possum impression while Patrick the amiable Nelson Mail reporter took indiscreet photographs of a recumbent recumbeteer.

Comparing notes with Nigel afterwards, Nigel too had lost a bit of skin off a knee: he'd slipped down in his seat at one point and was unable to wriggle back up while pedalling at full power, so the fairing rubbed a nasty little sore with every pedal-thrust. He was also having neck cramps towards the end, trying to flex his head backwards and forwards to ease the pain. But his familiarity with his bike was such that he was able to relax and let it move with the wind, and this is a very great credit to the fact that his machine had sound handling right from the start and even more of a credit when it is known that it was the first recumbent Nigel had built. (If I may digress again briefly, a certain friend of mine had some pertinent first-hand remarks to make about the necessity of absolutely sound handling on record machines after a certain incident which, in the event, may now be viewed by anyone: http://www.youtube.com/watch?v=i5Dapy1xUq0)

 
Therefore, at the moment, there is considerable jubilation in the NZ HPV community because two chaps in home-built corriboard streamliners managed to break a record that had been set fifteen years before, by a rider younger then that either of them are now in the world-record-breaking Kingcycle Bean. (Which you can see in a series of PDF photos by our Pete Cox at http://www.chester.ac.uk/scs/documents/cox_humanpower.pdf
which has as a bonus on p 44 a picture of my wonderful self standing, deja vu, beside Bob Knight not very many minutes before he lost half his skin at Abbey Park Leicester.)

 
However this delight is tempered by the galling knowledge that Claire King inside Mr Bird's head-in, hard-shell streamliner holds the UK women's hour record at 52.343 km and she's only a guuurrl. Therefore it is not hard to predict that further machines are going to get themselves built in due course, and that other racetracks up and down the country are going to find themselves surveyed, and that there is the distinct possibility of frightening the Manager of Invercargill which I am told has a temptingly wooden velodrome.
 

 
Nigel Farrell warming up

 

1) In the HPV world, Deadly Foes email and phone one another to offer help which I happen to know Nigel and Bob were doing well before the attempt, and they lend each other cordless drills and stuff on the day too. We are a gentle people.

Hour Record Broken 

Sunday, May 31, 2009 10:12:20 AM Categories: Bob Knight's fairing
As Mr Kingsbury used to say, The Boy Done Good . (I'm no good at Suspense.)
 
Also Urghhh is what I wanted to say, who invented alarm clocks? Up before dawn trying to think of everything that hadn't been packed the night before, and off in convoy to Nelson. Lots  of people - three - already milling around, and a frantic unpack until Bob and Nigel agreed with each other not to be so silly, they'd start at eight. This was to prove a Mistake as shall be revealed.
 
Lots of warm-up laps and so to business, I holding Bob up on the line and Mrs Farrell holding Mr Farrell up on the far side of the track. Mr Farrell - I wasn't close enough to see - may have received a good luck kiss; Mr Knight did not. The countdown and they were off, I running along holding the sides of the machine to prevent ignominious horizontality, my attempts to cheat by giving him a vigorous push being pre-empted by the fact that he pedalled out of my hands. And then they were on their own, and Mrs Farrell (it's Annalisa by the way and I didn't have to ask. I googled) sat down beside me and we settled to the ticking off of laps. All looked hunky-dory at first with each exactly matching the other's speed, and though Mr Knight was taking a slightly higher line on the track they were crossing their respective Start lines at exactly the same moment.
 
After an hour both of them had broken the NZ record but I'm kanckered (anag.) and about to go to bed because although all you rosy-cheeked yokels of Greet Maaaarsin'm Naarf'lk (for the NZ reader: Great Massingham; a noble city of several houses wherein the improbably named Niels Christian Arveschoug, famous Norfolk folk musician and an old mate of mine once lived) are up and planting turnips and so forth, we Colonials are frozen to our earthquakes and the sky is starry and frosty and the moon glimmers like a glimmery thing and actually I don't happen to have the exact figures to hand. I know one of 'em did 101 laps and a bit and t'other did 97 and a bit, but we want exactitude and I forgot to write it down and can't get the Results emailed to me until the morning. Besides the photographer has gone to bed.
 
Okay so that was a bit of a let-down, and here's another: it got so windy that for the subsequent race I tried my wonderful, beautiful, exquisite (get on with it. - Ed.) foam fairing for one trial lap and promptly took it off because the wind was steering the bike, not me. My fairing has a number of deficiencies, conspicuous among which being that it's useless.
 
I shall tell you all about these adventures tomorrow. Promise. (Maybe.) But there's a Clue in the preceeding paragraph.
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