TIG welding is perhaps best known for its industrial applications in fields like aerospace and aviation. Because of the precision and intricacy of the welds, it can produce in the hands of a skilled welder, and TIG welding also has a strong association with artistry and craftsmanship. That is why TIG welding is the method of choice among those who work with precious metals, including gold and silver.
The most substantial use of gold is for jewelry repair and fabrication, but it is also used with electrical contacts and in dentistry applications. Similarly, silver is used for jewelry, tableware, and heirloom pieces, but it is also prized for its electrical conductivity. Silver is frequently used in dentistry applications, as well.
Yes, you can TIG weld gold and silver! Here’s how. First, you need to have the right type of TIG welding equipment, starting with an inverter welding machine that can go down to a 1 amp start. Next, you will need a 50-amp torch and either .020 or .040 electrodes (for thinner material). And lastly, you will need pure Argon as your shielding gas.
With the proper equipment set up and familiarity with the right techniques, you will be on your way to TIG welding gold and silver pieces like a pro.
Equipment for TIG Welding Gold and Silver
There is a broad range of TIG welding equipment, most of which are better suited for commercial and industrial applications. Because TIG welding gold and silver is a far more delicate process than TIG welding stainless steel or aluminum, there are particular requirements for the equipment you will need.
The Welding Machine
Today’s welding machines feature numerous technological advances that make them more powerful than ever while still being energy efficient and easier to operate. Many models can be plugged into standard 120-volt outlets. When it comes to TIG welding gold and silver, there are several attributes that you need to look for in a welding machine.
One essential requirement is that the welding machine has a “pulser” feature that does three things:
- Adjust the pulses per second – the frequency of pulsing cycles controls the depth of the weld pool and usually corresponds to a higher quality weld because the increased agitation forces impurities to the surface. When dealing with thinner material, however, the welder must be careful not to set the number of pulses per second too high or risk punching through the material.
Thus, if the pulses per second are set to 3, the welding machine will produce 3 pulses per second, with each pulse consisting of a peak amperage and a low (background) amperage. If the pulses per second are set to 0.5, then one cycle will occur every two seconds (1/2 a cycle per second).
- Adjust the peak amperage – usually controlled via a foot pedal, with the set peak amperage ranging from 1 to 200. As a general rule, the higher the amperage, the higher the temperature at the weld point. For delicate work involving thin or small pieces, lower amperage settings will ensure the metal components are not damaged when TIG welded.
- Adjust the background amperage percentage – this is commonly a percentage of the peak amperage and typically set between 30-60%. Thus if the peak amperage is set at 100 amps and the background amperage is set at 45%, then each pulse cycle will modulate from a peak of 100 amps to a background amperage of 45.
Some TIG welding projects involving gold or silver jewelry will require low pulse frequency (one pulse per second or lower) and low amperage with welds a millimeter or smaller (in essence, spot welding), while others will require higher amperage of 100 amps or greater to penetrate into thicker metal pieces or to fuse large elements together.
Inverter Type Welding Machine
Using an inverter type welding machine to TIG weld gold and silver will enable you to plug into an ordinary 120-volt wall outlet and convert the household AC into DC electricity to power the welding torch. Built-in transformers help generate the power needed to work with these precious metals effectively.
This particular model TIG welding machine is popular among goldsmiths and noted jewelry fabricators.
The Welding Torch
In most cases, when working with precious metals like gold and silver, your materials will be relatively small, thin, or both. Therefore, it is important that you correctly size the welding torch according to the pieces that you will be TIG welding. Otherwise, you run the risk of burning through thin pieces or worse yet, reducing the gold or silver into a molten mess.
The ideal torch for TIG welding gold and silver will be a 50-amp micro-torch for smaller pieces and thinner material or a 125-amp torch for larger jobs or thicker material.
For intricate TIG welding of gold and silver, the micro-torch should be fitted with either a .020” (0.5 mm) or .040” (1.0 mm) electrode that extends ¼” to 1/3” past the end of the shielding gas ceramic cone. This torch set up will provide the greatest maneuverability around the material and allow for more intricate TIG welding to be performed.
Speaking of maneuverability, overly stiff cables, and tubes that supply power and shielding gas to the welding torch can hinder the movement of the TIG welder’s hand and impede accessing hard-to-reach spots. Flexible rubber cables will afford the highest agility and control over the angle of attack between the welding material and the tungsten electrode.
For thicker gold or silver material, you may find that the smaller diameter electrodes do not penetrate deeply enough or that they produce too small of a weld pool. In such cases, it may be necessary to switch to a higher-amperage TIG torch, which can accept a larger diameter Tungsten electrode.
There are special tungsten electrodes that are alloyed with 1-2% non-radioactive lanthanum oxide to provide enhanced arc-starting and re-igniting. Jewelers, metalsmiths, and artists seem to benefit from the greater arc stability as well.
Proper Sharpening of Tungsten Electrode Tips
The recommended electrode tip for TIG welding gold and silver is a fine point with a length (the portion that angles toward the very tip) that is roughly 2 ½ to 3 times the diameter of the electrode. Different thicknesses and metal types require electrodes to be sharpened a particular way for the best results.
When grinding (sharpening) the Tungsten electrode, hold it parallel (as opposed to perpendicular) with the grinding wheel, and gently rotate the electrode to achieve an even point. Make sure that there are no burrs on the tip as these will cause impurities during TIG welding. Do not use the same grinding wheel to grind other types of metal as the cross-contamination can cause impurities during welding.
For the shielding gas, it is recommended to go with pure Argon versus an argon mixture. Precise regulation of the argon gas is important to TIG welding gold and silver because of the smaller torch and electrode that will be used. Ideally, argon delivery of less than 5 cubic feet per hour will ensure that the gas shield is stable and does not impede or corrupt the TIG welds.
Setting Up the Work Piece
The chances are that the gold or silver material to be TIG welded will be smaller in size or thickness, so it is vital that the workpiece(s) be securely clamped and stabilized. A vise affixed to the end of an articulated mount can serve as a ground clamp. Another vital tool is a pair of welding pliers to help stabilize welded joints until they fuse.
TIG Welding Gold and Silver – Common Jobs
Most TIG welding projects involving gold and silver will be jewelry repair or fabrication jobs. Although there are other applications involving these two metals, the techniques and approaches will be similar.
Examples of Jewelry Repairs
TIG welding enables welders to quickly perform repairs to jewelry that are seamless and hard to detect. Examples of relatively simple repairs include:
- Re-sizing – the piece (for example, a ring or bracelet) can be enlarged by cutting the shank and adding metal via TIG welding (usually the bottom portion). The repaired section is then hammered smooth and polished, and the seam is virtually invisible to the naked eye.
- Repairing Cracks – utilizing a similar technique as re-sizing, cracks, or nicks in ring or bracelet shanks can be filled through TIG welding. The finished piece will be nearly flawless.
- Fixing Casting Defects – Occasionally, a defect will occur when a jewelry piece is cast. A common fault is pitting where there is a void of missing gold or silver material. TIG welding can either fill the void or through the use of fillet welds repair defects that are in challenging locations.
- Re-tipping – TIG welding can be utilized to repair or completely rebuild the prongs that hold gemstones in place on rings, lockets, broaches, and other pieces. The main advantage of TIG welding here is the resulting strength and uniformity of material (as opposed to simple soldering, for example).
- Channel Rebuild – Channels are the grooves or depressions into which a series of gemstones are laid to form a single line. TIG welding, in this instance, can rebuild the walls or banks of channels with the precision needed to ensure that the gemstones fit snugly and uniformly.
TIG welding is also suitable for more elaborate repairs such as those requiring the addition of new elements like a bezel, or reconfiguring existing elements such as expanding a channel.
Concerning any TIG welded joint, because there is a true fusion of materials, it is possible to achieve an exact color match, and the seam or joint is virtually undetectable. Furthermore, a TIG welded joint is a continuous piece of metal and as such, can be cold-worked (e.g., hammered, filed, polished) without the risk of cracking, splitting, or separating.
Fabrication Using Gold and Silver
With the full range of weld joints and weld types at their disposal, TIG welding is the method of choice for metal fabricators working with gold and silver, including jewelry makers. No process produces cleaner welds with the precision and intricacy of TIG welding, and the resulting joints are not only undetectable, but their strength is unsurpassed.
There are several advantages to TIG welding a jewelry piece together versus other fabrication methods such as casting.
- For intricate pieces, individual elements can be pre-finished and pre-polished before assembly, allowing areas that would be otherwise difficult or impossible to access, to be treated.
- Casting is often an imperfect process, with pitting and other types of voids in the material, being fairly common occurrences.
- There are specific details and features that casting and other fabrication methods cannot achieve.
- Pieces can be structurally stronger by reinforcing certain areas with TIG-welded supports, braces, and fillets.
In conjunction with casting, TIG welding can be used in the assembly process of pre-cast components to enable a more extensive scale fabrication of pieces, for example, a series of limited release items or specially commissioned jobs.
As TIG welding equipment continues to become more technologically advanced and in the process more straightforward to learn and operate, the applications of the TIG welding figure to expand exponentially. Compared to other metalworking techniques such as laser welding, brazing, and soldering, TIG welding has a nearly zero failure rate as far as cracking, pitting, and discoloration of precious metals.
TIG Welding of Other Precious Metals
TIG welding is becoming increasingly popular among metalsmiths and jewelers because it allows for artisan-like craftsmanship in creating intricate welds and joints, while also deeply penetrating thick pieces of metal and effectively filling voids of any depth. TIG welders also praise the degree of control they have over the molten metal.
Aside from gold and silver, TIG welding is a highly effective method of fusing other precious metals, including platinum, palladium, and sterling silver.
Platinum and palladium belong to the same family of precious metals, and both have a broad range of uses and applications. Platinum is used in jewelry (along with palladium, it is commonly used in the manufacture of white gold), electrical contacts, and laboratory equipment. Palladium is also used in electronics, in medical devices and fuel cells, and is used heavily in the manufacture of catalytic converters.
One advantage that TIG welding has over other welding methods is its ability to direct high temperatures with pinpoint precision without significant heat dissipation, thus leaving surrounding areas pristine. This is particularly valuable with platinum and palladium, which have significantly higher melting points than gold and silver (2,831° and 3,220° F compared to 1,946° and 1,762° F).
TIG welding of platinum and palladium produces nearly seamless joints and allows for intricate joints and connections. Because of the silvery-white color of platinum and palladium (they are often mistaken for one another), TIG welding of these metals is becoming the preferred fusing method among jewelers because there is no discoloration of the material.
The same is true for sterling silver, which is pure silver (92.5%) alloyed with another metal (7.5%) such as copper to give the metal mixture higher hardness and more rigidity. Sterling silver is used in jewelry, tableware, watches, and heirloom pieces.
Safety Considerations when TIG Welding Precious Metals
As with TIG welding in general, several safety considerations must be kept in mind whenever TIG welding gold, silver, and other precious metals. These precautions are particularly important in the jewelry arena because of the typically small, enclosed workspaces compared to more extensive commercial and industrial facilities.
Certain metals, particularly copper and copper alloys, can emit harmful vapors or gases during TIG welding so any workspace must be well ventilated. Good air circulation is also necessary because Argon gas can deplete the amount of oxygen in a small or enclosed area.
There are various welding helmets available that provide the necessary level of eye protection to safely TIG weld in any setting. For artisans and jewelers who frequently work with tiny and delicate pieces, there are welding helmets that have built-in magnification in the visors (e.g., 2X, 3X magnification).
If higher magnification is needed, there are special brackets that can be affixed to welding helmets into which lenses of varying degrees of magnification can be slid in and out. Even jewelers’ loupe lens holders can be adapted or fitted to a welding helmet.
It is not only the welder whose eyes need to be protected from the harmful ultraviolet light rays that emanate from the welding torch. Passersby also need to be shielded from potential injury from inadvertently walking into a TIG welder’s workspace. For this purpose, many TIG welders utilize welding curtains, which can be hung or draped around the workspace to block and filter all the harmful rays.
Hand & Finger Protection
Welding gloves are an absolute must for any welding activity to protect the welder’s hands and fingers from tremendous heat, flash burn, and sparks. TIG welding gloves are specially designed to provide maximum protection while allowing for unhindered movement as needed for this two-handed manual welding method.
Particularly when TIG welding precious metals, it is essential that the welding gloves be dedicated exclusively for TIG welding to avoid the possibility of cross-contamination with materials that can corrupt welds or cause impurities in the finished product.