Successful soldering can be the key to a wealth of creative opportunity once mastered, and there are a range of different methods which can be used to create a strong join. Regardless of which particular technique you favour, the basics of good soldering remain the same, so here is a quick reference list for anyone new or unsure of where or how to begin.
What is silver soldering?
Silver soldering is the process of permanently joining two pieces of metal together using heat to melt pieces of silver solder, which melt to fill a prepared joint. It is used essentially with silver for jewellery making and silversmithing, but can also be used to join together copper, gilding metal, brass and gold if needs be.
Are there different types of silver solder?
Yes. There are four grades of silver solder (hard, medium, easy and extra easy), which all come in strip form and have different melting temperatures.
Silver Solder Strip
The idea is to use them in sequence starting with hard which has the highest melting temperature, so it can withstand prolonged heating as you perform subsequent joins – below you will find a guide to the melting ranges of each type of solder:
|Hard||745 – 780°C|
|Medium||720 – 765°C|
|Easy||705 – 725°C|
|Extra Easy||655 – 710°C|
How do I heat up the metal to solder?
The heat for soldering is provided by a blowtorch. They can be small and portable if you are working in a limited space, or larger and more complex if connected to a gas bottle via rubber hoses if that is preferable. Both types produce a hot flame through a combination of oxygen and gas (normally propane, butane or natural gas), which is regulated by a valve to control the mix thus altering the size and intensity of the flame.
What is flux?
Flux is essentially a cleaning solution which is applied to a solder join prior to heating. Solder will not run without it, so it is an absolutely vital component of every soldering process. Flux comes in liquid (Auroflux) or paste form (borax dish and cone), and is applied with a small paintbrush.
Where can I do my soldering?
Soldering must be performed on a heat resistant surface which can withstand and absorb the intense heat. A small working area can be easily constructed using heat resistant sheets and bricks (asbestos substitute, magnesia, charcoal etc.), which are perfectly adequate for most small scale soldering jobs. Larger jobs should only be carried out in a purpose built soldering hearth, with adequate ventilation and full fire and safety precautions.
How do I clean metal after soldering?
Jewellers use a cleaning solution called Pickle (Picklean) to remove oxides and dirt which build up during soldering. The solution can be used warm or cold, and the jewellery is simply immersed in it until clean.
Soldering Step by Step
- Clean and de-grease metal to be soldered using files and emery or wet and dry paper.
- Ensure the metal to be soldered fits as closely as possible (you shouldn’t be able to see through the joint).
- Apply flux to the joint and heat gently to dry.
- Apply tiny pallions (pieces) of silver solder along the join. The solder should also be clean and grease free.
- Heat the metal evenly using a fine flame. Keep the flame moving and watch constantly as the metal starts to glow a dull red.
- As the metal reaches temperature, watch for a flash of silver which means your solder has run. As soon as this happens remove the blowtorch.
- Allow the piece to cool and place in a Pickling solution to clean.
NOTE: if the solder has not run or has not formed a successful bond, you will need to clean your item thoroughly before trying again following the steps above.
Once you have mastered the art of the basic soldering process and you are more familiar with the right tools for the job, you will be able to move onto more complex soldering projects.
Want to make sure your workshop is well-equipped for your next jewellery soldering project? Learn about essential soldering tools along with tools for many other jewellery making techniques with our Beginners Guide to Jewellery Making Tools, which can be viewed for free online here.