The operation can be performed quickly with a gas lamp or torch. This material is rather simple to use, which does not require special knowledge and can be acquired in any large DIY area. The goal is to penetrate tin between the copper tube and the connection to perfectly secure the two parts to be assembled and seal the assembly. There is little risk of error.
Thoroughly clean the end of the tube with steel wool until the tube clears.
Coat the part to be welded with a paste or a suitable etching powder which facilitates the welding.
Heat the tube and apply a thin layer of tin over the entire surface to be welded.
Place the fitting and warm up again. Bring the tin into the gap between the tube and the fitting.
Once completed, the fitting can be recessed or boxed, it does not need to remain accessible.