Satisfactory soldered joints in precious metal articles must be strong yet unobtrusive. The basic principles of soldering practice must be applied to ensure strong consistent joints along with the following points:
• THE DESIGN MUST LEND ITSELF TO SOLDERING. • THE PARTS TO BE SOLDERED MUST FIT CLOSELY AND ACCURATELY. • THE CORRECT SOLDER AND FLUX MUST BE USED.
Gas and compressed air mixtures are generally the most satisfactory for torch soldering. Fine adjustment of flame size and temperature are possible. The flame should be kept constantly on the move over the whole joint area or over as wide an area as can be conveniently joined in a single application of solder.
If the size of the joint or the duration of heating is large further flux additions may be made during the process.
JOINT PREPARATION
• The joint areas must be free from dirt and grease and ideally cleaned with a file or emery paper to ensure the solder will wet the parent metal. Flux should be applied to the joint area and solder prior to heating.
• Fluxes promote wetting of the workpiece by the molten solder. They do this by removing any oxide films present on both the parent metal and solder and prevent further formation of oxides during heating. The flux must be completely fluid and active before solder liquidation and should remain so until after the solder solidification.
SOLDER PASTE
Rather than buy separate solder and flux, solder paste comes conveniently mixed together in a syringe.
To solder an item of jewellery simply apply the paste to the item that needs soldering, remove excess paste, apply heat to solder as normal. Using solder paste means that you do not have to apply flux and solder separately. The syringe aids easy application and helps remove the tricky problem of getting the solder to balance on the item before it is soldered. The solder paste mix ensures that solder will not ‘jump’ off the item when heat is applied.
FLUX Flux is applied where an item needs to be soldered
• The flux helps the solder to flow into the area to be soldered. If solder is applied without flux, the solder will not flow, forming into a ball or simply not melting and sitting on the surface of the metal. If your solder does not run freely, check that the joint is clean and that there is flux on the surface.
• It must be noted that warming of the workpiece may be required to ensure full retention of the flux paste over the whole joint area. The torch should initially be held some distance from the workpiece so that the flame heats the work generally. If components of different size are being joined the torch should predominantly heat the heavier item.
ALL ALLOYS AND SOLDERS SUPPLIED BY COOKSONGOLD ARE MANUFACTURED CADMIUM & LEAD FREE
They comply with the requirements of Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards Annex XVII requiring a maximum cadmium and lead content in any material sold for jewellery purposes of 0.01% and 0.05% respectively.
FOR MORE DETAIL ON INDIVIDUAL ALLOYS WE HAVE A RANGE OF DATASHEETS, AVAILABLE TO DOWNLOAD FROM COOKSONGOLD.COM 58 Click cooksongold.com Call 0345 100 1122
