Wednesday, 22 February 2012

Front Wheel Spoke Flanges - part 1

Well I was wrong, it turns out that you can cold set 4130 tubes. You just need a long enough lever. The bearing housings are now almost perfectly aligned and even though the original error was small, it would have bothered me. I'm like that.

So this week I've been making a pile of very expensive swarf chips by machining a large chunk of gunmetal into slightly smaller spoke flanges. As I expected the gunmetal machines beautifully. At one point, when I was removing a large volume quickly, I had a fountain of chips spraying off. Unfortunately, I was machining in short sleeves and lightly toasted my left arm.

Starting with this billet, amongst other things, I made some...

...very expensive chips.

The first step is to thin the billet down to the correct outer dimension 
and bore the centre deep enough to make two flanges at one chucking.

Aside from my own measurements of originals it is interesting to compare
against the actual specifications from the literature of the time.
This is from 1887, a few years earlier than the original I am copying.

Next step is to bore the recess for the inner bearing race, this is the final part of the
labyrinth seal. Also face the outer edge of the flange at the correct spoke angle.

Then I needed to machine the inner profile of the flange, 
this had to be done carefully to be an accurate facsimile of the original. 
Also round off the top of the flange and machine a groove to locate
 the spoke holes in the centre. Finally part off and make the twin flange.

Next job is to remount each flange the other way around and 
bore the slight recess for the hub and round off the shoulder.

And finally, I get the opportunity to use the keyway 
slotter that I bought years ago and have never used.

The completed flanges with a length of key steel used to lock them to the hub.

I'm pleased with the appearance compared with the original.

Next week I'll drill and tap the spoke holes.

In other news, we have much sadness now that my parents have gone home. To take our minds off this we accepted an invitation to a veteran car event here in Christchurch. We had a decent 50km ride on the Saturday which was hard on the way out and then tailwind home, magic. The following day we assembled in the Botanical Gardens in period costume and had a posh picnic. Several members couldn't resist showing off for the tourists and performed penny farthing trick riding on one of the lawns. My Son was over the moon when he was offered a ride in an 1899 steam Locomobile in beautiful condition.

video

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