Thursday, March 29, 2012

Sailing

One of the locals who's sailed all his life says I'm quite right to stick with a tiny boat that you can get into the water on your own. He had a big yacht in the drive for years but seldom took it out. Since I painted the Optimist he's got all enthusiastic, & says he ought to get a dinghy again. He told me a rounded hull in a small boat is not as stable as a hard chined boat, and when you get down to Optimist size the flat box shape is best. Which is zackly what I've found. You push it off from the beach and when you jump in, the wide flat bottom stops it tipping straight over. He said a clinker-built boat of that size is more work to make, more expensive, and doesn't perform as well. Which was trés interesting, because I've always known you can't scale Nature but hadn't twigged there were certain critical sizes in boat design. He told me that the next size up from the Optimist, the P-class, popular and faster, has a heavy, decked hull and one person can't pick it up and move it around. His favourite ever dinghy was a Junior Sunburst but Googling has failed to elicit anything other than the fact that it was nine feet long.

The Optimist is designed for one kid up to the age of fifteen. When John and I were in it together it was Dead Slow, and only fun cos John spent the whole time laughing at me. There's something mathematical about displacement which you could probably calculate though it's complicated by the curve on the bottom of the boat, and there's something else to do with (mass on board = stability) versus (sail area = speed). Obviously I'm thinking about building a boat even though I probably won't. One parameter is the amount of space inside the van, so a boat could only be 3 inches wider and 19 inches longer, and then it would be heavier and cumbersomer and need a bigger sail which I'd have to buy and sails are trés expensive whereas the Optimist cost $400 eight years ago and doesn't owe us anything. There are lots of Optimists and they're about $200 to $800 for a wooden one and the wooden ones are indefinitely repairable and the plastic ones are dearer. Edward Heath says in his autobiography that the most fun he ever had was sailing dinghies, and I think I now see why. A bigger boat would require a trailer and a trailer would need a Warrant of Fitness - a MoT - and would take longer to rig and get into the water and I bet I'd not use it hardly ever at all, if you can use something not hardly ever at all.

Sailing stops when you find wet soggy patches and have to sand & dry & fibreglass & let it harden & paint it and I can tell you that nobody ever saved money on disposable rubber gloves, but I'm not going to in case you suspect that I tried to and got epoxy all over my trousers. The soggy patches were on the front right corner and the back left corner and the starboard gunnel. The starboard gunnel is the right-hand top bit, but We Sailing Folk have special names for everything to make You Landlubbers feel insignificant and inferior. - You will detect all the zeal of the convert, a sort of combination of crass ignorance of what I'm talking about and over-exuberant evangelism. People who actually know about boats ruminate thoughtfully and don't talk about it, which is the biggest lie I've ever told because if you go to a library you'll find shelves of books about sailing. Except here. Where there are barely a handful of books. Which is moderately bizarre given Motueka's proximity to the sea. There used to be a book called Low Resistance Boats by a Thomas Firth Jones and luckily I made notes, but when I went to check something I found they'd discarded it as being old. I think the librarians have only a vague grasp of what a library's for. These days it's packed out with tourists on laptops rather than books.

Anyway, I have applied vast amounts of epoxy and fibreglass and in a fortnight I'll be able to go sailing again and the wait doesn't bother me a bit because I've discovered you need two things and they have to coincide. You need a lot of wind and a high tide. Tides of 3.7 metres aren't enough in the lagoon because you have to tow the boat through acres of mud before you reach water deep enough to deploy the keel. And morning sailing is rubbish because the land warms up during the morning and there's no wind till lunchtime. So there are only a few days a fortnight when it's possible.

A beautiful repair. So why does Mr. Knight make cruel remarks about my workmanship?

When both apply - wind and tide, that is - then it's a merry hour of adrenaline because an Optimist is only slightly bigger than a plank of wood and when the wind whips up the lagoon presents waves higher than the side of the boat. And you can ignore that stuff about baling because when you're watching every wave and the wind's blowing 25mph and you're hanging onto the mainsheet as if hanging onto the mainsheet's going to be of any help, then you haven't got time or a free arm for baling.

It's a fraught business, I've learnt. You're trying to balance inside a tiny floating box in big waves with no control of the accelerator and little control over direction or stability. The error penalty is being tipped into the sea, plus or minus drowning. The sole benefit is that should you survive, all those books by Uffa Fox start to make sense and you begin to understand what a weather helm and a lee helm might be and what luffing is and why gybing isn't as safe as tacking and what all of those strange words mean anyway. And I see the programmers who did my computer didn't sail because there are red wiggly lines under luffing and gybing, so here's my glossary, a mercifully short one because I'm a novice and haven't yet found out what the front right and back left corners are called.

Gunnel. A gun-wale. A wale is a plank though I don't know why. I thought it was called a strake. The guns were poked over the top, obv., so the top plank is called the gun wale.
Sheet. A rope. Gah? Why? Sounds like a sail. I suppose sailing predates comfortable beds, a relatively recent phenomenon. And what did Vikings do?
Port. A side.
Starboard. Another side.
Starboard is the steer board, and it goes back to when William the Conqueror knitted the Bayeaux Tapestry and revealed that he didn't have a rudder so he had to stick a big wide steering oar over the right-hand side, and since it got in the way of docking at Southampton or wherever he did dock, he called one the steering board and t'other the port side. My, I'm clever. One day I'll grow up and go and study linguisticks at UCL where they occasionally wheel Jeremy Bentham's corpse to academic meetings and Minute him as Present but not voting. Nope, not joking. He had himself publicly dissected and stuffed, both according to his will. He founded UCL and his body is kept on public display in a glass-fronted case a bit like a large phone booth and you can go and see it if you want. They messed up his head so that's only a wax model, but the actual head's preserved somewhere, I forget where but I bet you could Google it. All you really see is his clothes stuffed with straw but I believe his actual skeleton's inside, probably held together with a few bits of gristle. Gruesome, eh? Rumour always had it he was Minuted as 'Present but not voting' at all meetings, but actually I think it was only twice. Exceedingly clever man, and one of the early champions of women's rights. - We lack a Jeremy Bentham here in Motueka so we always take our visitors to the top of Takaka Hill where there's a tumbled-down shed in which a cow mummified itself many years ago, and everyone just loves it. It's called The Dead Cow Walk. We tell them in advance and they get all excited and morbid, and we do the whole walk and there's no dead cow, and as we walk back to the car park they get all miffed and say 'Where's the dead cow then? You promised us a dead cow' and we point them to the crumbling wooden shed in the little field next to the car park and they go over and get all spooked out, because it's a complete skeleton with the skin entire and intact, but everything inside has been eaten away. Looks a bit like a fibreglass model, and everyone thinks that's what it is at first. Eeeeeee. All your friends' children think they're in heaven. - Actually, if you visit the Moyses House Museum in Bury St Edmunds they keep a book of the Red Barn Murder trial which is bound in the skin of the murderer. Now that is gruesome. I saw it when I was twelve and have never forgotten it. Yeuuuuuuuuuuuuuuch.

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Saturday, March 17, 2012

Bushes

Oh pig, John's high racer needs bushes and bushes are very easy to make on a lathe but I am stupid and incompetent to a degree unparalleled even by an apprentice from Wisbech when it comes to a simple item like a bush and a complicated machine like a lathe.

I made bushes. I made them out of nylon. I inserted them in the swing arm pivot housing. I reamed them with my home-made reamer, which is a 12mm tube with an angled end, the edges filed smooth and then stoned razor sharp. I fitted the inner pivot tube and one of the little bastards bloody well rotated in the outer pivot housing, which has its ERW ridge inside left intact to prevent exactly this from happening. I was MAD.

I took it out and fitted a shim and put it back and did all the swearing that accompanies fitting a shim, and it still bloody well rotated in the outer housing so I was STILL mad.

I haven't got much machineable nylon left. It all came from World Hero Mr. Sleath, who used to live near me in Leicestershire and who used to build recumbent trikes and recumbent bikes and model boats and who kept a small wind tunnel in his garage and three lathes and a milling machine he made while he was a student and some inexplicable stone otters that he had trouble moving, when he moved, which he did no doubt as a pre-emptive measure to stop himself feeling lonely as soon as he found out I was about to emigrate. Anyway one day at a race in - what’s that place called - sort of not-quite-figure-of-eight-track not quite near Ashby de la Zouch - Curborough, knew I'd remember - he came up and dumped a bag in the boot of my car and when I got home I found it full of acetal off-cuts, and since acetal is as expensive as bronze I was one of the happier people who hadn't won any of the races, which I never did, except for only once when I sort of cheated. (Got in a train with Nick Martin, who had to brake at the finish line so's we'd come in equal first. You don't get that sort of sportsmanship in the UCI.)

A drill press, this morning. 2 reamers, 2 munted bushes, 1 hole cutter, 1 donor acetal offcut, 1 usual benchtop mess

So, out with the pre-munted nylon wheel and using a hole cutter in the drill press, and at slow speed so's not to melt the nylon, and lots of short cuts ditto, I hole-cutted (p.t. of to hole-cut. Like hacksawed, not hacksawn.) into being a 19mm rod of nylon with a ¼ inch hole down the middle of it and popped it the 3-jaw and proceeded to machine one end exactly a millimetre too small for the outer housing because I am really, really stupid and truly incompetent and unbelievably impatient and grossly careless and sometimes I hate m'self and I don't know why Mr. Knight of the village of Near Christchurch or Mr. English of the village of Near Canada continue to talk to me. Mr. English has just won a whole lot of accolades in America. His engineering is a bit better than mine and his bikes don't weigh quite as much. - He wishes to know, in passing, why there isn't a country called Canadia:

I just got back from the big (ie biggest) handbuilt bike show (the name does seem a misnomer; I assume they conveniently forget that all the Chinese, Taiwanese and Indians use their hands to build bikes too (Chinese are from China, why aren't Indianese from India? Something like the Canadians from Canadia. Or something) - Rob

So then - back to my bad machining again (we leave, with reluctance, Mr. English's geographical musings) - I said quite a lot of the words, quite a lot of times, that one does say on such occasions.

And I turned the rod around and machined the other end so it would be a really, really tight fit in the outer housing, and drilled - with a drill - a 12mm hole through it, and parted it off, and hammered it into the outer housing and when it had just entered I squeezed it into place with the vice and behold! it went in properly. Leaving too tight a 12mm hole, of course.

But luckily Scott at Rural Supplies had managed to get me a 12mm reamer. An or'nery reamer was $98, and an adjustable reamer was $28, so I'd ordered the adjustable one and was surprised, opening the grease-packed bag, to find it was made of blackened mild steel and was stamped India. So you get what you pay for.

Mind, my brother, who's a proper engineer like Mr. Sleath and Mr. English, tells me he buys

pretty decent machine tool parts from RDG in England.

And if RDG, whoever they might be, would care so send me one for nothing by way of gratitude at this free advertisement I shall be most pleased, but I expect they won't, because as far as I can detect the only people who read this blog are Room 3 St Joe's School, and I can't imagine too many of them will be in the market for machine tools.

But as things turned out it was perfect for reaming nylon because I could adjust it to take a succession of light cuts and end up with a good smooth firm fit, and so it proved and I was happy in the end, which isn't always the case when I've been in the workshop. Didn't even cut m'self this time.

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Monday, March 5, 2012

John's High Racer continued at last

Right, the time has come to Get On With It, which is to say I got out a drill and put a wire brush in it and spent half an hour removing rust from the frame of John's High Racer that has languished these months on the workshop floor, tripping me up and generally getting in the way because I'm too untidy to find a place for it and too disorganised to finish it.

The rear triangle, it will be recalled, fell off a perfectly good gentleman's mountain bicycle when a hacksaw was judiciously applied. The main frame is a two inch 18-gauge mild steel tube because it's cheap, available, weldable, and has proven strong enough in 12 of the 32 machines I've built. (I've just counted them. I think the number's right, unless I've forgotten some, which is likely since my memory is rubbish.) The other 20 machines were strong enough - my ego has just told me to clarify the point - but didn't use two inch tubing.

Okay, this machine - reminding myself - is to be high enough to be seen by the driver of EMM397 - a grey BMW, the Ultimate Driving Machine - who stopped me to tell me I was invisible, one of those delicious ironies of which the General Public are capable, and it has 26 inch wheels because I have an abundance of them and of the frames whence they came, and it has rear suspension because I don't fancy adding it later when John discovers the pleasure of comfort. The BB is 6.5 inches above the sitzhöhe to minimise frontal area, and it has a straight chainline so I don't need idlers. You can get a straight chainline with big wheels. It's one of the advantages. The sticky-up bit at the back is to assist in alignment and will be sawn off later. The swing arm pivot is wide because I have experienced rear swing arms twisting under hard cornering, and the reason I didn't use large diameter bushes in the BB shell is because I'm stupid and didn't think of it in time. The wide bearing is offset to the left so it doesn't interfere with the chain line.

The welly boots in the background are because there was a torrential rainstorm last night, so torrential that they called off the Iron Man competition round Lake Taupo suggesting a depressingly obvious pun. We are getting lots of Weather here in the Pacific yet never once does anyone on the radio dare mention the words 'climate' and 'change' in the same sentence, and indeed it amazes me how completely people block this issue out of their heads, given the implications of what the Royal Society (warning: pdf.) tell us. - Well it doesn't amaze me actually. It's all to be expected. - But let us not give way to gloomy thoughts. Let us hope for better things. Let us flatter ourselves that I may be the survivor.

There are two methods of aligning front and back wheel. The first is to bolt each set of drop-outs to the lathe bed of a Dean Smith & Grace weighing five tons, and the second is to tack-weld one side-plate and then wrestle with the rear swing arm while simultaneously welding the other side plate and not electrocuting myself at the same time eyeing everything up to make sure it's in line. This, naturally, is difficult. But it is easier than taking the whole contraption 44 kilometres away to the nearest Dean Smith & Grace which in any case I wouldn't be allowed to use as a welding jig because - well, I don't suppose I need say why. Anyway, with the aid of John, who is tolerant of his father's heated vocabulary during this sort of procedure, I got it all tack-welded up and then I fitted two wheels and then I set it up as shewn (why d'you have to spell it 'shown' these days?) and then I held up a front triplet such that the innermost chainring was the statutory 37mm off the centreline and then I saw that the chain would run straight through the RH side-plate because I was so focussed on the profile of the bike that I forgot about the salient fact that chains move sideways when derailleurs are applied.

*uuuuuuuuuuck.

How many machines have I built thus far?

So. What to do?

First arrange for CT scan to see if cranium still houses brain.

Then tack-weld the triangle to the mainframe with judicious additions of scrap-iron.


Then snap off the RH side-plate; cut out template from an old tin; put plaster on finger where sharp end of tin penetrated blood vessel because I am too impatient to put leather gloves on & do the job safely; bend template; mark and bend RH sideplate; saw and file excess steel off-ov same; bolt everything back together and re-weld; and finally cut off the scrap iron and un-tack-weld the rear triangle.





Didn't take very long, but this is why when Her Majesty gets round to handing me a peer's patent, which has thus far slipped her mind, I am going to take the title Lord Foolish McIdiotperson.

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