③Welding

After finishing the milling process, it is time for welding the pipes and build our frame.

We need to carefully and tightly the frame in our iron jigs to thermal deformation as much as possible during the welding process.

Due to the seat type, the seat tube and collar are brazed raw.

When melted brazing becomes hot water, then you can finish off the brazing/welding process.

And then, we weld the seat pipe to the BB.

Heat distortions occur every time, so we use a jig to necessary tuning.

Water drain holes done one by one like in the drawing.

Make sure each step follows the drawing.

Finally, we do a assembly of the 3 parts.

We fit it in our jig, to be able to check if size and dimensions are correct.

Jig is made from steel to guarantee distortions.

After the fitting and tuning, we measure the dimensions of the tubes.

If all OK, the small parts can be welded to the front triangle.

Time for the back triangle.

Making the chainstay and seat stay.

Because it is a cross, these bikes are subjected to bending, twisting and eventually some crushes too while doing their work.