TIG Torch Size: 17 vs 26 vs 9, Which to Choose?

What the numbers on a TIG torch mean

When you read a TIG welder listing, you will often see a torch named with a number such as 9, 17, 20, or 26. These numbers are size codes used by torch makers, and they tell you two things: the amperage the torch is rated for and the physical size of the torch head.

A lower number, like 9, usually means a smaller, lighter torch rated for lower current. A higher number, like 26, means a larger, heavier torch that can carry more current. The number is not a measure of quality; it is a measure of capacity and ergonomics.

For example, a 9-series torch is often used for low-amperage work where you need fine control and easy access. A 17-series torch is a common middle ground, and a 26-series torch is built for higher output and longer duty at higher currents.

• 9-series: small, light, rated for lower current, good for tight spaces and thin metal.
• 17-series: a common all-around size, rated for medium current, balances reach and capacity.
• 26-series: larger and heavier, rated for higher current, suited for thicker metal and longer welding sessions.

Amperage rating and matching to your welder

The amperage rating of a TIG torch tells you the maximum current the torch is designed to carry continuously. If you exceed that rating, the torch can overheat, which is why matching the torch to your welding current matters.

Your TIG welder's output range is shown on the listing, often as a range like 10-200 amps. The torch that comes with the machine is usually chosen by the maker to match that range. If you buy a separate torch, you need one whose rating covers the amperage you plan to use.

For a 120V TIG welder that tops out around 125 amps, a 17-series torch is a typical match. For a 240V machine that reaches 200 amps or more, a 26-series torch is more common. A 9-series torch is for low-current work, often below 125 amps, and is not meant for high-output welding.

Access and ergonomics: why size matters

Beyond amperage, the physical size of the torch head affects how easily you can reach the joint. A smaller torch, like a 9, fits into corners and tight spaces where a larger 26 torch cannot go.

A lighter torch also reduces fatigue during long welding sessions. If you do a lot of intricate work, a smaller torch can be easier to control. But a smaller torch may not handle the current you need for thicker metal.

The trade-off is between capacity and access. You want a torch that can carry the current you need without being so large that it blocks your view or cannot reach the joint. Many welders keep two torches: a small one for fine work and a larger one for heavy welding.

Reading a TIG welder listing for torch size

When you compare TIG welders, look for the torch size in the listing title or the bullet list. A title might say "TIG-200P ACDC PRO" and the description may mention a CK17 torch or a 17-series torch.

If the listing does not state the torch size, that is a missing detail. You can ask the maker or seller which torch is included. The torch size is part of the kit, and it affects what you can do with the machine.

Some listings name the torch by brand and model, like "CK17" or "CK20." These are specific torch models from a maker, and the number still follows the same size logic. A CK17 is a 17-series torch, and a CK20 is a 20-series, which is similar in capacity to a 17 but with a different head shape.

Air-cooled vs water-cooled torches

TIG torches come in two cooling types: air-cooled and water-cooled. Air-cooled torches use the surrounding air to dissipate heat, while water-cooled torches circulate coolant through the torch handle.

Water-cooled torches can handle higher amperage for longer periods without overheating, which is why they are common on industrial machines. They require a water cooler, which is an extra component and adds cost.

For most home and farm TIG welders, an air-cooled torch is standard. The amperage ratings on air-cooled torches are lower than water-cooled versions of the same size, so a 17-series air-cooled torch may be rated for less current than a water-cooled 17. For more on this distinction, see air-cooled vs water-cooled torches.

If you are buying a machine that includes a water cooler, the torch will likely be water-cooled. Otherwise, plan on an air-cooled torch and match the rating to your welder's output.

What to pick for your situation

For a first TIG welder, the torch that comes with the machine is usually a good match for the welder's output. You do not need to buy a separate torch unless you find the included one too large or too small for your work.

If you do a lot of detailed work, consider a 9-series torch as a second option. If you weld thicker metal and need higher current, a 26-series torch may be a better fit, but check that your welder can drive it.

The torch size is one of several details to compare when choosing a TIG welder. Look at the welder's amperage range, input voltage, and included accessories, and match the torch to the work you plan to do. Multi-process welders often include a torch sized for their TIG output, so review the specifications carefully.

• For general home and garage TIG work, a 17-series torch is a safe all-around choice.
• For low-current precision work, a 9-series torch offers better access and lighter weight.
• For high-output welding on thicker metal, a 26-series torch provides the capacity you need.

What to pick for your situation

Questions

What does the number 17 on a TIG torch mean?

The number 17 is a size code that indicates the torch's amperage rating and physical size. A 17-series torch is a common all-around size, typically rated for up to about 150-200 amps, and is a standard choice for many TIG welders. For more on choosing a TIG welder, see our TIG welder guide.

Can I use a 9-series torch on a 200-amp TIG welder?

A 9-series torch is rated for lower current, often up to about 125 amps. Using it on a 200-amp welder at high output could overheat the torch. Match the torch rating to the amperage you plan to use. For high-output machines, a 26-series torch is a better fit, as explained in our 200-amp welder guide.

Is a 26-series torch better than a 17?

A 26-series torch can handle higher current and is larger and heavier. It is better for high-output welding, but a 17-series is lighter and easier to maneuver. The best choice depends on your welding current and access needs, so review the TIG torch cooling options for more detail.

Do I need a water-cooled TIG torch?

Water-cooled torches can handle higher amperage for longer periods, but they require a water cooler. For most home and farm TIG welders, an air-cooled torch is sufficient. Check your welder's output and duty cycle to decide. See the air-cooled vs water-cooled torch article for a detailed comparison.

How do I know which torch size is included with a welder?

Look for the torch size in the listing title or description. If it is not stated, ask the maker or seller. The torch size is part of the kit and affects what you can do with the machine. Our TIG welder buying guide lists models with their stated torch details.