Frequently Asked Questions
What is Laser Welding?
Laser welding is the fusing of metals using light as the energy source. Laser is the acronym meaning Light Amplification by the Stimulated Emission of Radiation. We are using a machine that creates a beam of light (1064 nm wavelength) to weld and fuse metals together — almost instantaneously.
Why may I want or need a Laser Welder?
Laser welders allow the user to assemble or repair jewelry (or any metal items) very quickly, and very efficiently. The laser beam is very small (.2mm minimum diameter) and the heat zone is very minute. This allows you to apply heat in areas you normally wouldn't with a torch, such as near gemstones, springs, enamels, antiques, eyeglasses, etc. The weld is three times stronger than solder, and there is no fire scale, boraxing, pickling etc. Preparation work is minimal and clean up is with a rubber wheel and an ultrasonic. Most jewelers are telling us that they are at least 50% or more productive with a laser welder.
Should I get rid of my torch if I get a laser welder?
No! The laser welder is to be added to your tools to give you greater capability. It was not designed to replace your torch. There are many times when the laser can be used in conjunction with the torch. One example is positioning a peg setting with the laser and then soldering it in place so that the solder runs up and around the peg and gives that nice round and smooth filling appearance.
How hard is it to use a laser welder? What is the learning curve?
The laser welder is very user friendly and the learning curve is relatively quick. Someone can be welding in a matter of minutes but to become efficient takes a few weeks with an hour or so of practice each day. This may vary depending on the user and the complexity of the applications being attempted.
How is the energy of a laser measured?
The energy is measured in units called joules. A joule is how many watts of power is being put out for how long of a duration (voltage and milliseconds). It takes anywhere from 4 to 8 joules to weld platinum. It takes upward of 30+ joules to work with silver.
Can you laser weld titanium?
Yes you can laser weld titanium, but you have to use argon as a shielding gas to prevent oxidation. If you have any oxidation when you weld titanium, the weld will look good but it will be brittle. It is also important to know that there are many grades of titanium, and you will find that some work better then others. When repairing eyeglasses made from titanium, you will find that you will need to introduce a bonding material. We use hard silver solder or white gold.
Why does white gold get cracking around the weld or simply not hold together?
When welding with white gold, you have to use low power settings, or you can cook or crystallize the metal. You need to use low voltage and low milliseconds. A small amount of black around the weld is acceptable, but having a lot of black and looking like lava rock, means that you have too much power. Argon shielding gas can not help with welding white gold. It can only hide the fact that you have too much power.
Why do some golds require different settings than others?
It depends on the alloys used to make the gold. Red gold or rose gold uses a lot of copper. Copper is very conductive, so it requires higher power and time settings. Green gold uses a lot of silver, and silver is also highly conductive and reflective.
What about welding silver?
Silver is one of the most difficult metals to weld because it is highly conductive and reflective. A trick for working with silver is to use a blue or black permanent marker to mask the area where you are welding to help cut down on the reflectivity and absorb more of the light rays (think of wearing a black tee shirt out on a sunny day). It is also useful to use hard silver solder wire as a bonding agent when working with silver. If you can't use solder, then try to use a very fine diameter silver wire (30 gauge or smaller). The smaller the diameter the less energy needed to fuse it to the parent metal.
Can you laser weld stainless steel?
Yes! Stainless steel welds very easily and with low power settings. Sometimes, it is a good idea to use argon shielding gas in the weld to prevent oxidation and impurities that make it brittle.
Can you size rings using a laser welder?
Yes! Sizing a ring can easily be done with a welder, although it must be done properly with sufficient penetration into the shank. Sizing with a laser welder can take more time than with a torch, but the sizing will be stronger with no descoloration due to the solder (especially with platinum), and you don't have to worry about high heat destroying other components on the ring, such as gemstones.
I see Laser Radiation stickers on the machine. Is this radiation dangerous?
The radiation is not dangerous in the sense of toxic or electromagnetic radiation such as x-rays and gamma rays. It can be harmful to your eyes if directly exposed to the light rays. These lasers welders are technically Class IV Lasers because your hands are exposed to the light rays and can possibly be burned. Your eyes are protected in many ways. There is an LCD safety shutter that blocks the light rays on each pulse (this is the blinking you see on the screen when the machine is firing). There are also protective coatings on all optics and glass in the optics path that will not allow the dangerous wave lengths to reach your eyes.