11-3-2019
Good weekend of work. Although our schedules did not align for much time, Miles and I made every second count. All necessary holes for component mounting were drilled into each frame piece, and the battery support brackets were fully welded on. I certainly had ample time to refine my drilling/measuring technique.
Due to material shortage, we scrounged up some rusty 1 inch square stock with a slightly larger than 1/16” wall thickness. We used it for the battery support pieces and all the structural crossmembers that will hold the two frame halves together. The sandblaster played a key role in making the heavily oxidized tube look nice and metal again. Unfortunately, we did not to tack weld the entire frame+crossmember assembly, but will do it on Tuesday when we can afford the time to do it carefully.
We applied some tips from a local bike builder, John Cutter, to make the building/welding process easier. Centerline tacking makes a huge difference in preserving geometry and planar-ness. Some notable mistakes must also be mentioned. For future iterations, we need to go lighter on the weld beads on the inside faces of the frame. Excessive time was spent grinding down the built up welds to allow the crossmember pieces to sit flush between the frame sides. This is wasteful in time and material.
Finally, we put our heads together and brainstormed jigs for the head tube and bottom bracket. For both areas, we settled on two part fixtures to maximize plumb/squareness and will 3D print them sometime later this week (hopefully). We’ve decided to cut all the flange pieces with a bandsaw instead of a water jet like we were hoping. That’s it for today, more to come on Tuesday!