Sunday, May 20, 2012

Tube bender

This week it went through my mind that Mr. Knight would like me to build a wooden three quarter inch tube bender more than he would like me to make a hardened steel one like his, and given the fact that that this surmise was either correct or incorrect, I have to admire myself for nearly getting the Right Answer. He nearly wanted me to build one. I betook myself to the lathe anyway, and for a happy hour sprayed myself and the inside of my overalls and the inside of my welly boots and the inside of my hair eyes socks and unmentionables with applewood shavings, and ended up with a variety of rollers with approximate three-quarter inch grooves in them. How does an applewood shaving penetrate overall, trouser, thermal, welly and end up on the inside of a sock? Why they bothered with the Large Hadron Collider when there are greater mysteries to be solved I do not know. I wore a hat and ear defenders and goggles and a face mask and the shavings penetrated all of them.



When I had rollers I made some bearing holes in some planks (applewood of course) and a handle (applew.) and using quite a lot of hands and knees and teeth managed to wriggle some clamps in place to hold a three-quarter inch tube firmly in place and then I applied a bending force. Luckily I had envisaged that a tube bender would be useful to make seat tubes.



Unluckily it was rubbish. It was as useless as a useless thing invented in the useless department of a useless laboratory by a rubbish inventor and made by a rubbish technician whose strength calculations were absolutely rubbish and it didn't work at all. It was weedy. It was pathetic. It was like a flimsy thing made out of three pounds of applewood and not like a stout unyielding thing made out of half a ton of cast iron. I jumped about on the end of the lever and had no effect whatever. When I looked at the tube it was still straight and although I narrowed my eyes and pursed my lips it merely smirked at me.

One of the rollers had got itself sawn in half and half remained untouched. In a prior retail expedition to the junk shop I had found one of those Odd Things that you don't understand but know you'll never see again so I'd bought it in case it turned out to be a Useful Thing and it sat about on a bench until Mr. Johnson pointed out that it was a pipe clamp. Mr. Johnson is a Member of the Diaspora who came to live in New Zealand forty years ago, and is related to Dr. Johnson who wrote the first dictionary so when he tells me something's a pipe clamp I incline to believe him. He owns a Myford lathe that was personally given to his father by Edgar T. Westbury. Edgar T. Westbury was a Director of Myfords, which fact was not advertised in any of the vast multitude of his Model Engineer magazine articles. There's nothing new about Product Placement.

Combining half-roller with pipe clamp was the work of a moment, and behold! there was an alternative tube bender.



Well it works, sort of, except with a lot more crinkles than nudging a bit of tube along in a vice, though it does have the mild advantage of allowing you to see how long your bent tube will be before you bend it, which I found difficult juggling tube and roller and vice and steel ruler.



The encouraging thing is that three-quarter steel tube is amazingly hard to bend. This means that when welded into a seat frame it will remain hard to bend, and the webbing will stay tight. Which is what everyone has already found empirically, so it isn't really news.

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Tuesday, May 8, 2012

Bike computer failure

Mr. Knight and I have both recently watched a truly magnificent film of how a bicycle was made in the Raleigh works in Lenton, and in view of the fact that he tends to blog on a Wednesday night I shall pre-empt him by adding this Link today. Lenton is a suburb of Nottingham and when I lived there a million years ago one of my neighbours must have been the man who filled 1,000 hubs with ball-bearings daily, a career, in the event, that didn't have a future, unless he moved to China of course. I shall also pre-empt him - Mr. Knight that is - by including this truly magnificent picture showing how much water there isn't on the planet and this will be easier because Mr. Knight doesn't discuss global water plenitude with the avidity he reserves for other topicks.

Fresh groundwater and surface-water make up the bubble over Kentucky, which is about 252 miles in diameter. The sphere over Georgia reresents fresh-water lakes and rivers (about 34.9 miles in diameter).

All Earth's water, liquid fresh water, and water in lakes and rivers

Spheres showing:
(1) All water (sphere over western U.S., 860 miles in diameter)
(2) Fresh liquid water in the ground, lakes, swamps, and rivers (sphere over Kentucky, 169.5 miles in diameter), and
(3) Fresh-water lakes and rivers (sphere over Georgia, 34.9 miles in diameter).
Credit: Howard Perlman, USGS; globe illustration by Jack Cook, Woods Hole Oceanographic Institution (©); Adam Nieman.

It doesn't seem possible - that there's actually hardly any water that is, not Mr. Knight's lack of enthusiasm for volumetric ocean measurement - since if I walk down the road there's water to the edge of the horizon. But the average ocean depth is only 2.6 miles, so this picture is accurate. If I was a Clever Computer Person I'd add a bubble representing all the air we have, and it would have a meagre 17% bigger diameter. Unfortunately I'm not a Clever Person at all. I'm a Computer Spastic. I got my road bike down off its hook and the tiddly little computer was dead and all I knew was that you can sometimes resurrect them by taking the tiny battery out and momentarily putting it back the wrong way. Unfortunately this means you lose not only the data but also how big your wheel is and that means getting out the sheet of 'structions. Oh *uuuuuuuuuuck. The sheet of instructions is about the size of an OS map and nearly as hard to unfold and when you've unfolded it you have to find the bit that isn't in Singaporean Dansk Poliski Espanol Francais Magyar Deutsch Nederlands Espanol no I've already done that Portuges Italiano or Cestina. (Where the *uck's Cestina?) And there in a small corner is the bit in English and a Fat Lot of Good it is too.
Press Set and Mode. All Clear. Display Time. Press Mode button for Odo. Press Set button twice. Hold A for two seconds, press three times, press once for Miles, press B. Udskiftning af batteri no turn the sheet over cos that's the Dansk bit. Where were we. Press Mode. Press Mode. Press Mode. Press Mode for two seconds. Now you have set L = 216cm. *uuuuuuuuuuuuuuck! I didn't want L = 216cm.
I knew it would be bad. I'm still traumatised from having to reset my watch to cope without Daylight Saving (Press L. Press A. Hold C for three seconds. Press L. Press C three times. Press L to move to the month setting. *uuuuuuuuuuuuuuuuck! Didn't want to do that. Press A. Press L twice, press C once. Press A for two seconds, hold L and C and press A twice. *uuuuuuuuuuck. Place watch in bottom of tea-towel drawer because now the alarm's set for 4 am and I don't know how to unset it.)
What Mr. Knight and I like is Bicycles because they're uncomplicated and all you have to do is bend bits of tubing to make the seat frame, which require no 'structions at all but do require me to study that How a Bicycle Is Made film again because it has a cunning machine like the plumber's got, which if I manage to make it with applewood formers will mean my bent tubes don't look like the horrible mess that they always do look like.



Here are the seat parts for John's High Racer, the incomplete shards of which have got on my nerves again, scattered all over the workshop. I'll leave these ones as they are. They'll make Mr. English feel smug about the High Offroader he's building.


Off-road machine being built to commission by Rob English

They won't make Mr. Knight feel smug because I'm such an infinitely more careful workman than he will ever be, and anyway I also once lived in Lenton, the centre of the glorious, if by 1946 slightly moribund, British Empire, where a skilled worker fitted the wheels to the bicycle, not just a junior worker. (You didn't just watch the film? Do. Seventeen minutes and twenty-three seconds of pure engineering bliss.)

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