Wednesday, August 02, 2006

Keel is Laid

I'm on the road rather than in the shop. The last week was a blur, with so many activities that it was hard to keep track what day it was. My hope was to finish Aram's frame and get it off to paint, but there was simply too much else going on.

Still, I stayed up late a few nights and made some progress. First, the chainstays were mounted in the bottom-bracket. The bottom bracket spigots required some grinding to allow for the 120mm rear end. After pinning, alignment was checked with the Bringheli table and looked good, so it was on to brazing. Post brazing, the stays were pulling together a bit. This was probably caused by more heat on the inside of the stays whiling pulling filler around the joints. A little cold set fixed this, along with a final check-out on the table.

Then everything when back into the jig to fit up the front and back ends together. When all looked good, the down-tube and BB where sanded and cleaned with some of Freddy's Al-Tife. Everything got fluxed up, the joint was put back together on the jig, and the pins were set.

Checking this on the alignment table, I began to see the limits of my cheap surface gauge. I'll probably want to get a good height gauge someday.

Anyhow, after a bit of fussing, things looked good, so I hung the assembly from the track-forks and brazed up the joint. This came out looking clean and neat - which is nice because cleaning filler around the bottom bracket is especially difficult.

Onto the table to find that the downtube was drooping by 1/2mm at the end, and that there was a slight twist to the head-tube. Bending a 35mm down-tube takes some work - but in short order the droop was gone.

Joe supplies a nice jack with his table. This was set below the head-tube in line with the axis of the down-tube. Then a long bar was fitted to the head-tube and the twist eliminated.

After re-checking everything we have a complete straight keel. By then it was 2AM, and that was time to quit.

More when we make progress again.

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