Jewellery laser welding FAQ

In the run up to the Jewellery & Watch show, Chris Ogden, our business development manager for industrial lasers, answers some common questions on jewellery laser welding.

I will be at the NEC from 7 – 11 February at the Jewellery & Watch show with the brand new Piccolaser PL55, showing how it can help you create amazing jewellery, faster. Just pop along to stand 17S48 to take a look and have a chat about how our machine can help.

I’ll be around during the show to answer any questions, but in the meantime here are the main questions I am most frequently asked about jewellery laser welding.

How does laser welding differ from conventional welding and joining processes?

Jewellery laser welding systems use short pulses of high energy to melt metal in a fraction of a second. Because the laser uses a beam of energy, no combustible gases or solder materials are required, making laser welding a clean process that produces neater and consistent results quickly.

Are special electrical services required?

No, modern laser jewellery welding systems will operate from a single phase electrical supply and from a standard 3-pin plug socket.

Are any special gases required?

Argon is usually used as a shield gas to prevent discoloration and oxidation on some materials (like Titanium and Stainless Steel). However, this is not always used by jewellery companies and is generally not required with Silver, Platinum and Gold. If it is used, it’s only when the laser is about to pulse, so usage will be very low. You can get small, cheap cylinders from most gas suppliers and other outlets.

What features should I look for on a jewellery laser welding system?

First and foremost, you need a system with a suitably powerful laser for the work that you will be performing. This is very important and so it’s vital to learn about the technical parameters of laser systems.

You should also consider whether you want a system with a powered z-axis and a powered movement table – these are very useful and can help you achieve much neater results than when positioning a part by hand.

Some systems have cooling gas options as precious metals can get warm when you work on them. Good lighting is also important, and an integral fume extraction should form part of any system. Always try a system before you buy it and test it on all of the materials that you might want to weld.

What should I look for in the technical specification?

Key parameters are the peak power and average power, but also look at the spot size that can be achieved as well as the frequency (or repetition rate).

What do all these terms mean?

It’s a good idea to visit a laser company and get them to explain these to you and how they might affect you. But the most common terms are:

• Average power: This is the amount of energy that the laser transfers in a given time. This is not generally the best parameter to consider with a laser welding system.
• Peak power: This indicates how much energy can be delivered in a single pulse, which is very important for jewellery welding. The absorption and reflective properties of precious metals can mean that higher parameters are required to weld specific precious metals.
• Spot size: The range of spot size or weld seam size that a system can deliver. This can be altered to a spot size as low as 0.1mm on some systems, up to 2mm.

What safety features are built into lasers?

For jewellery welding you should probably look to buy a Class I laser welding system. This means that the laser welding usually takes place inside an enclosed welding chamber, with safety features built in to protect the operator and others from harm. Anyone who uses a laser welding system should be trained in its safe use as well as potential hazards, all of which are easy to understand.

Which precious metals can I laser weld?

All precious metals can be laser welded. 9ct and 18ct Gold and Platinum are quite easy to laser weld. Pure Gold and Silver in particular require more laser energy to laser weld, so if you need to weld these metals look carefully at the peak power of a system. As a rough guide, 8kW or more should be required to weld these metals.

Can Titanium and Stainless Steel be welded?

Yes they can, but you should definitely look to use Argon as a shield gas if you weld these.

To find out more, visit the Laser Lines stand at Jewellery & Watch at the NEC (stand 17S48) 7 – 11 February, 2016, or call Chris Ogden at Laser Lines on 01295 672588, or email lasers@laserlines.co.uk.