Soaking metals ? One finds two great families: the alloys coppers and beryllium or copper, nickel and tin, this last representing the majority of soaking metals. They are known under the names of Nicaflor 1000 (copper, 10% nickel, 6% tin) at Cottet, Nibrodal (copper, 15% of nickel, tin 8%) at Öga and Marius Morel, Niculan at Exalto-Oxibis... ? When one welds the components, nose, circles and tenons, the heated matter becomes soft. With materials soaking, one resolidifie matter thanks to a thermal 370° treatment after their working, to find important mechanical characteristics. What ensures a strong solidity and allows, therefore, design of very fine mountings.