Once the rolling of the body and of its foot is ended, we procede separately to their welding.
This produces a cylinder (body) and a cone (foot).
The languid is joined to the foot : the languid is a little metal plate with a percentage of tin ranging from 10% to 70%. Afterwards, we have to connect the body to the foot. Similarly to the previous stages, this process also requires a prior dyeing, with red paint, for the parts to be soldered.
Now the pipe has taken shape. It is cleaned up from the paint through an ultrasound machine that make it possible to dissolve the protective substance without harming the metal. For the larger pipes, for obvious reasons of volume, the procedure is carried out through manual washing.
The final operation involves an accurate polishing done manually for small flues and with the use of a specialized machine for the largest ones.