Take a look at the finished bicycle here..

Friday 8 July 2011

Head tube.

While trying to move things on I thought I would have a go at assembling the front end of the bike. Stating with the head tube I proudly got out the head set, lined up the pieces and offered the top bearing cup up to the head tube. It didn't fit. Not just in a small way, there was just no way it was ever going in. For those of you who are reading this having made your own frame from scratch, you will now be realising how green I am to this.
I was worried that I had bought the wrong size tube or head set or both. On double checking, I had the correct ones.
I decided to swallow my pride and put in a call to the guys at Ceeway where I had bought the tubing from. They were very patient with me and explained all about reaming.
Reaming. The tubing is sold with an internal diameter that is slightly too small for the headsets. This is because as the frame is braised, distortions occur and the tubing is often not as truly round as it should be. So when the braising is complete, the frame is 'reamed and faced' to true it up and cut it out to the correct size for the head set.
So my head tube needed reaming. The tools I needed were easy to find but very expensive, so a quick web search brought up Argos racing cycles, bespoke frame builders and restorers, who are fairly local to me. I nipped over one lunch and they were more than happy to do the job for me for a fraction of the cost of the tools. Perfect. I pick it up next week.

Frame tacked together for dropout measuring.

In addition to the front end shenanigans, Lew and I have been mithering about with the drop outs. The actual drop outs have been bent to match the angles of the stays. Lew bent the stainless drop out sections with an oxyacetylene torch. The next step is to make the tube fittings to fit the wood. As mentioned below, we have revised the plans for this a couple of times, and we think we have now got a simple and effective way forward. The only recent change in plan is in how to physically join the drop out plate to the tubing. Normally a simple butt would be used and braised together. However because of the over sized tubing I need to accommodate the wooden stays, a butt was not going to work as well as we thought. It would need an insert made, and that is just too much machining for this project. so we have decided to try and squeeze the ends of the tubing into an ellipse using a jig, to take the shape of the drop out and make the braising more straight forward. Lew is testing this weekend, I will reveal the out come soon.

As you can see above I have put the frame together slightly more formally in order to get the drop out angle was right. I found that by the bottom bracket I needed a wedge, as my initial measurements had been wrong. Nothing a bit of resin and a bolt cant mend.
It was also an opportunity to start putting some of the bolts into the frame. The first being the bottom bracket ones. These now go thought the metal fin inside the frame and it is rock solid. When the frame has its final lamination (when the head tube is done) It will re-enforce it again.

I also need to start thinking for a name and a badge to put on the front.

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