Aligning the rear triangle redux

December 11, 2009 · 0 comments

JigsInFixture1I think I now have a good solution for aligning the front and rear triangles for fitting the connections and for holding them in place while brazing. I thought I could get away from having an elaborate fixture for this project and I think I achieved that. I’m taking advantage of my welding table which (so far) is really square and level. It also turns out to be the perfect length for this project as you can see in the photos.

JigsInFixture2I can set the head tube angle relative to the welding table surface. This should make the top tube roughly parallel to the welding table. I’m going to lower the bottom bracket slightly which should increase the head tube angle, the seat tube angle, and give the top tube an upward slope. This should make for a softer ride. The lower bottom bracket drop will lower the center of gravity which should improve handling as well.

JigsInFixture3The current bottom bracket drop is about 3cm. I will increase the head tube angle by 1-2 degrees which will drop the bottom bracket.

Previous post:

Next post: