Tuesday, March 25, 2014

Takaka Hill

On Friday while cycling up Takaka Hill there was a curious squeak-squeak-squeak noise from round a corner, whence suddenly appeared this:

It continued to squeak all the way down the hill below us. It now has a flat roof over the top, prob. to keep the sun off though my spies tell me that it's a solar panel for power-assist. Even so I admit to being hugely impressed that anyone could have ridden over the hill on it. (Identified here)

One normally thinks of cycling over Takaka Hill as dangerous, and flying as safe, but since 239 people have vanished in the mystery of the Malaysian aeroplane all statistics have gone out of the window. For seventeen days the world has paused to puzzle over what happened. Warships have been diverted and aircraft are scouring the ocean for signs of wreckage. We're a wonderfully generous species in caring for one another. I can't imagine what the search for the dead bodies would have cost.

Meanwhile 4,000 children died of starvation today, and another 4,000 died yesterday, and a third 4,000 died the day before. Luckily they're all poor so they don't matter and certainly aren't worth the world's media making a fuss about. We're a wonderfully selective species in choosing what and who to care for.

Meanwhiler, we continue to buy more and bigger television screens which demand more and more power, and we now fit them to several walls of our houses to save the inconvenience of having to stay in one room while watching Top Gear, and the people who try to inform us that a quarter of the atmosphere's excess carbon dioxide has been released since 2,000 continue to be ignored by the world's businessmen and politicians and farmers and doctors and office personnel and road repair men and supermarket checkout-chicks and - well, basically, all of us. Serious analysis tells us that the world can afford for all of us to live like the Chinese, which means that we have to get rid of everything we own and maybe keep the fridge, a plastic washing-up bowl, and a bicycle or (while the oil lasts) a small moped if we're especially privileged. This means all of us wherever we live and it includes Germans, the French Finnish and Dutch; the Swedes, Danes, and Norwegians; the people of Israel; Tony Abbott  and Rex Tillerson ; and the worthy citizens of Dubai. (The English needn't: they're a Special Case.)

Naturally this perturbs me greatly, because I have just re-commissioned my lightweight Peugeot with a pair of 700c wheels I found at the dump, only one of which needed a couple of new spokes. I got the gears, cables, changers, levers, chainrings, cluster, bars and stem off the Bike Heap, though the chainring is from a MTB and has 175mm cranks which I don't much like. But with a 42/32/22 and a 14-28 I can climb Takaka Hill without my kneecaps popping off, so it's a minor inconvenience. And the whole weighs no more than 22lbs, as all good bikes should. 

 Yet another hack bike.

But that still means I have too many bikes. It was, admittedly, a free bike because someone gave me the frame but free bikes cost the following:
$69 for pedals (the old ones were knackered and didn't fit my cleats)
$140 for a saddle (no decent saddle ever comes off the dump. Good saddles are only bought by experienced cyclists and they've too much sense to throw them away.)
$40 each for tyres (good tyres are the key to easy riding. Always. No exceptions.)
$11 each for inner tubes. (I never begrudge paying for them. The bike shop has to make a profit somehow or it will go broke and I won't have a ready source of spares nor a skilled mechanic to offer friendly advice.)
So that's a total of $311, which isn't as free as I shall tell my wife. (Don't worry, I can say what I like here. Wives never look at your blog.)

Note cunning item 1: puncture repair kit rubber-banded to steering head tube, and cunning item 2: handbrake made out of interlooped rubber bands cut from an inner tube. This Hugely Clever Invention (I thought of it, though I 'spect quite a lot of other people have too) saves having a kickstand.

And never fear, I am very humane too, and shall cycle up Takaka Hill tomorrow and see if the elevation means I can help spot the wreckage of MH370.

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Sunday, March 9, 2014

Rudder mounts

In a brave endeavour to sustain interest in this truly glorious and wonderful account of my proa build I have laboured all weekend (liar) to put the rudder mounts in. For starters I cut oblong holes in one side of No 1 hull. It having long been established that I am stupid and useless and everything I do is some kind of bodge, nobody will be surprised that I had to chop bits off my finished pieces to get them through the holes. The middle bits were too big; god knows how, but they were. While I was about it I drilled some 25mm holes in them for pintles. I would have drilled 25.4mm holes but for the fact that Sandvic only make 25mm hole saws, the rascals. A pintle - since my computer draws wiggly red lines under it - is what boat people call a Pin Tail, and it's what a rudder pivots on. Boat people - this has long been established - are incapable of encountering a word with more than one syllable without suffering an unconquerable urge to reduce it to something unintelligible. (Or as they themselves would put it, Bpleellible.) I don't know if I'll use 25mm pintles, but by drilling holes now it makes it a sight easier to do so later. The Optimist has little stainless steel eyes for its pintles, but stainless steel = £, and since I have applewood in abundance and since cog pins in waterwheels were made of applewood and lasted forty years of use, I have a fancy for wooden pintles. - This may have to be revised in view of shipwreck, if there is a shipwreck anon, & if it is caused by broken applewood pintles.

Next I cut a stick of wood the same length as the deck is wide (A, above), and jammed the sides apart with it. Then I stuck the top rudder-mount through the hole, and fiddled around more-or-less endlessly with files and saws and general wood-chopping implements until the inside end mated with the far side. A temporary screw goes into the side of the hull and holds it in place while the glue goes off.

Then I stuck the bottom mount through t'other hole, and in order to make these two mounts parallel I cut a short plank (B) to jam the far ends apart, and a short stick to jam the near ends apart (C), and with a lot of fiddling round with a 22mm pole (D) - because I didn't have a 25mm pole, only inch ones - persuaded myself that both sets of holes are in line. There are two lots of holes because I haven't designed the rudder yet, and I haven't done this because I'm stupid; see endless blog entries.

Today saw lots of epoxy mixing and gap filling and whatnot, and, not having measured beforehand, I was pleased to find the whole is only 27 inches wide because that means it goes through the workshop door to sit in the sun and harden.

My wife, meanwhile, went and bought herself an old plastic kayak and with all the confidence of maritime ign'rance stuck it in the sea and paddled it to Split Apple and back, befriended off Kaiteri by a seal and accompanied and misguided by an experienced canoeist who shall remain nameless because he didn't have a lifejacket and hadn't tied his paddle to his boat, both of which are
a) stupid
b) irresponsible
c) illegal.


Wednesday, March 5, 2014

Bike trailer

A daughter - we shan't discuss who - has commissioned a bicycle trailer for shopping, to save herself the great labour of hooking panniers on. Actually I suspect that she (correctly) divines that I like bicycle trailers, having made a number of them.

Here it is, awaiting Mr. Knight's painting and lining-out, which I'm quite sure he will be pleased to do on so exquisite a piece of workmanship.

Full of the conceit of thinking I know what I'm talking about, and fuller of the other conceit that anybody out there in the Wide Wide World (www.) wants to know my opinions, here they are on the topic.

1. A one-wheeled trailer is good for those conditions where one must seek a single track. Otherwise, two wheels are more stable. And unless wide handles are provided, a one-wheeler can't readily double as a handcart.

2. Twenty-inch wheels are ideal. Bigger wheels may collapse sideways under load. BMX wheels can be had with 14mm axles, and if you get the cheap ones with cup-and-cone bearings, you can winch the axle over to one side and use it as a stub axle. Big fat BMX tyres afford nice suspension. But beware ordering tyres, because there are two sorts of 20 inch wheel, and 406 (BMX size) tyres won't fit 451 (Bike Friday, Raleigh Twenty) rims.

BMX wheels with 14mm axles, wound over as stub axles. Simple welded z-frame as the axle.

3. There are two sizes of sixteen inch wheel, too.

4. *uck bicycle makers are stupid. Whitworth should have been in charge.

5. Phil Wood hubs were made for wheelchairs, and may still be. They have 11mm stub axles, and won't tolerate big wheels or heavy weights. Any stub axle under 11mm will bend. 12mm or more is best.

6. Tracking's the hardest part. The wheels have to roll parallel to one another or you're a skier with your skis pointing together, and
a) the rolling resistance is massive and
b) the tyres wear out. Very quickly.
I measure between the rims with one of those telescopic lecture pointer thingies, making sure the gap between the front of the rims is the same as the gap between the back of the rims.

Here's how I got the axles in line, and the wheels parallel

This one ended up as a dung cart with space for two plastic dustbins

7. If you have stub axles, Derek Henden's Bike Hod is a fine example to ape. It has a simple hitch - a bit of hydraulic hose with a hole in it, though drilling the hole is a Mission because hydraulic hose is made of wire mesh covered in rubber, and you can't drill wire mesh. I don't know how I managed it.

8. If you haven't stub axles, a flat-deck trailer is a good design to copy. Each wheel sits between two rails. Very easy to get the tracking right.

9. You can't tighten a stub axle on box section. But it's easy to make a spacer to slip inside the box section, and then you can.

Phil Wood hub. 11mm bolt through box section stiffened with inserted 16mmOD (12.7mm ID) tube, 349 rim & tyre

10. Overall width of 24 inches is ideal. Narrower is unstable, especially lightly loaded. Wider and it hits doorways. A standard doorway is actually 28 inches wide, but I'm so inept a bicycle-navigator that 28 inch wide trailers always bash the doorway's paintwork.

I made this ages ago. At 18 1/2 inches wide overall, it was far too narrow and very tippy unladen.

11. The hitch must be in front of the bike's rear axle, or any weight in the trailer will lift the bike's front wheel, sometimes alarmingly.

12. A hitch next to the wheel axle, on the left of the bike to avoid the derailleur mech, is excellent but will need additional handlework if you ever want to wheel it round like a handcart.

13. A hitch on the seatpost is also excellent but any sideways movement of the bike exaggerates wiggling of the trailer.

14. Minimising the unsprung load is all very well, but suspension is heavy and the loads are light. Fat soft tyres work well. A sprung trailer with a sack of wheat on it set up a large sideways oscillation, and proceeded to take over the bike's steering.

This had suspension, but it swayed under load, and later got converted into a wagon front axle.
The wooden box for it was pretty, but very heavy.

15. Kiddy-trailers make an ideal shopping trailer. That's why you never see them for sale second-hand.

Other people have other views, and will have to advertise them accordingly.

Here's an inadequate photo-essay on Jane's freshly-built Shopping Trailer.

Start with one of those crappy fold-up chair frames. Found, as always, on the river-bank.

Reduce to component parts. The tubing is under 1mm thick, and 16mm OD. Very light.

Unf. very light = very brittle, and when bending it in my improvised tube-bender (a pulley wheel and the vice) it snapped.

Start again by thinking how to use various sawn-up rear triangles

Square off in the four-jaw two inch-sections of 2mm wall inch-section, and drill 11mm, insert spacers, and weld to a 17-inch bit of 1mm wall box-section. Phil Wood hubs are 3" wide, so total trailer width is 23".

Add bits of the chair-frame only where they don't suffer any great stress. This trailer's pretty flimsy, but it's only going to take a cardboard box of groceries, and it weighs a meagre 10 lbs.

Paint white, then see if it will attach to bike. Use exhaust clamps from local garage, which are cheap and plentiful.

Find ancient rucksack, throw away frame, steal estate agents' sign, cut and fold into tight-fitting box, affix sides with zip ties, stuff into old rucksack.

Drop the box onto the trailer.

Use those elastics that you pick up from the side of the road to attach box to trailer frame.

Pause and admire your cunning workmanship

Hitch trailer to daughter's bike.

I asked Jane if she was taking it with her, but learnt that it is merely for the next month's groceries. After that it becomes another Father's Shed Wall Decoration.

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