Thursday 30 May 2013

The Spoon Brake

I've spent this shedweek making the spoon. Of the various original geared faciles that I've personally seen, I've yet to find one with it's original brake. Even the one I am copying has a modern replacement, it's just a rough casting that still requires finishing. I've seen a few others that look like they are made from the same casting but never an original. So this week I have been in touch with a well known collector from the States who has owned two originals and still has one of them. I discovered that he is the source of the castings that I've been finding scattered around the planet. He had them cast using one of his originals as a pattern. He also very kindly sent me some good clear photos of how his looks when mounted. My lever will be slightly different since I have the deep drop bars but I can adapt the style to suit. I was also interested to discover that his estimate for the total surviving number of geared faciles is only 12+ worldwide. In return for all of this information, I've promised to send him a scan of an original 1885 Ellis & Co. brochure from my own archive.

When I measured the original bike I traced the outline of the lever and spoon even though they weren't original parts. This was fortunate since they were cast from originals and so are accurate (if slightly too small) to copy. What I wasn't sure on was how the lever and spoon interacted, the photos cleared this up. Choice of material is important when making these parts. Even though you are only applying hand pressure, the force at the spoon, due to mechanical advantage, is considerably (3 times in this case) higher. I'm pretty confident that I could bend mild steel of this gauge with 3 times my hand force. I searched around for some higher tensile plate that would take the force, I ended up buying some 1/4" Bisalloy 80 (roughly 3X yield strength of mild steel) mostly because the local supplier had some offcuts and it was cheap. Except when I got it home I found it was 6mm. Unless I use shims I'll have that authentic brake rattle common to most antique bicycles.

First mark out the shape of the spoon using the original as a pattern and roughly cut it out. Then drill the pivot hole. Bisalloy 80 is hard to drill, the manufacturer recommends cobalt drills. I just used HSS at a lower speed and it was OK. Then assemble and mark where the spoon will sit so that it contacts the tyre with as much surface area as possible.

The spoon itself is made from a scrap piece of thick wall water pipe.

Make a jig to hold it all in the right place...

...and take it to Tweed Pete to weld up. 
I asked him to build up a decent fillet so that...

...I could then dress it off and make it look organic and beautiful. 
Like melted cheese or something.

Then make the top pivot pin, this is machined in the lathe from a high tensile bolt and then the upright is shaped so that it sits at the correct angle relative to the lever. This angle is important, the angle when it is in the off position should be the same as the angle in the on position relative to the brake lever it passes through.

Reuse the same jig and take it back to Pete...

...to get it welded up. The thread is just used to hold it in the jig.

A stunningly bad photo of the finished spoon in situ.

Next week I'll start on the lever itself. It's a little more complicated than the spoon.

In other news, I was riding the motorbike to work this morning. Taking a right hand bend into a T junction when, accompanied by a loud report, the rear tyre parted company with the rim. As you can imagine this is not an ideal situation to be in when leant over on two wheels on a frosty morning. For safety reasons, I tend to prefer my tyres to be firmly attached to my rims. By sheer skilliance I was able to not fall off. I pushed the bike home, changed my underpants and then had to spent the morning running around like a blue arsed fly trying to get the tyre replaced. It's an odd size (of course). Unfortunately this time I can't blame Mr. Middleton for my two wheeled misadventure.

I've also lashed out on some modern riding gear. I last bought a motorcycle jacket when I was 17, a long time ago. I still think it's the height of fashion, an opinion not shared by my children. Or my lovely wife. This new one has all sorts of body armour and such like contrivances to assist your comfort level when sliding down the road. My wimp glands decided it may be prudent to invest in suchlike technology.

The bike has been causing me some trouble just lately, first new chain and sprockets, then new front tyre, then the starter motor packed up and now this. I'm having to bump start every day since I'm still waiting for a moron on Trademe to send me a replacement starter motor but that's a story for another day...

Thursday 23 May 2013

Road Trip




America is quite a big place you know. I know this to be true because over a period of two and a half weeks I dragged the extended whanau around California and Nevada in a big van.

A big van last week.

Since we live in New Zealand and all other family members live in England we consulted a globe and decided that California is roughly midway. About a hundred years ago I spent time working in various parts of America but I'd never been to the west coast. Well goodness me, isn't San Francisco a pleasant city? I was very taken with the place and it's people, a view probably enhanced by the kindness shown to us by a local wheelman. I would like to publicly thank Christian Wignall and his family for going out of their way to make us feel welcome and entertained.

Almost as soon as we arrived I had been loaned an 1888 New Rapid for a guided tour of the area. New Rapids have a well deserved reputation as high quality machines and I was very excited to have the chance of an extended ride.

Christian with some wonderful engineering and a big bridge in the background.

Christian has done extensive research into the company and he had published this a few years ago in the Veteran Cycle Club journal. I thought that I recognised the name. An online version is available here, I urge you to take a look.

The next day Christian took me to meet Greg Barron of Rideable Bicycle Replicas. I needed to buy some tyring (or tiring since I bought the US system) and Greg was very happy to give us a tour of his workshop and his collection of antique bikes.

Greg's unique storage solution.

Whilst there I was pleased to be introduced to a few other wheelmen.

Greg Barron, some other bloke, Christian Wignall & Mike Walker.

Later we drove down to Half Moon Bay to visit Jack Castor and his amazing collection. I had briefly met Jack once before and it was good to renew his acquaintance.

Shite and Briny the next day we picked up the van and started the road trip. Highlights in no particular order would have to include.

Yosemite National Park, all of it. 
We stayed here for a few days and did and saw many exciting things.

Black bears, a mother and her cub just a hundred meters or so away. 
Quite close enough thank you very much.

Yosemite does waterfalls very well indeed. This is Vernal Falls.

Snakes and lizards, my son was in heaven, my lovely wife less so. 
This dinosaur was *this* big.

White water farting. 

Ghost Towns in the desert.

Death Valley, what a fascinating place! We stayed the night at the aptly named Furnace Creek, being spring it was only a mere 115F (46C). I was pleased to find an early example of Mr Starley's tricycle balance gear on an 1894 steam tractor. More massive but just the same technology.

How do you differentiate between different differentials?

Dried up and not quite so dried up salt lakes, the most famous being Mono lake. 
Ducks float ridiculously high in the water.

A helicopter flight into the Grand Canyon. It really is a very big hole indeed, so big that our feeble minds can't really comprehend the scale even when you are there staring at it and you know the statistics.

The Colorado river is a mile below us.

Riding over the Golden Gate Bridge. Christian once again assisted us with a loan of a bicycle each and also acted as our tour guide. Later we had a personal tour of all the really steep streets in San Francisco that they don't put in the guide books. Not on bicycles I might add.

The cable car museum, my son and I spent a very happy afternoon here. We now understand how the cable cars can cross other cables. Of course we immediately had to go out into the street and find examples of all the engineering solutions we had just seen described.

My idea of heaven.

Meanwhile my lovely wife took my daughter shoe shopping. I had failed to warn the shoe shops in advance but I think the staff coped reasonably well. Details are unclear at this stage of the volume purchased but I've found at least two new pairs in her shoe room.

Because the light is better in my workshop, that's why.

Las Vegas, not my cup of tea I'm afraid. I tapped a bronze statue outside Caesar's Palace to discover it was fibreglass. Pretty much sums the place up.

Outdoor Escalators. Seriously?

Normal service will resume next week.