Good welding needs a good electrical circuit through the work piece
Besides operator skill, the most common cause of poor welds is a bad ground.
Without a good ground, even experienced, highly skilled welders will have issues.
You don’t want shallow penetration, porous joints, excess slag or inconsistent beads.
Some of the most respected names in the market cut costs with cheap ground clamps.
Fortunately, ground clamps are not expensive and they’re easy to replace.
A Quick Comparison
| Product | |||
|---|---|---|---|
| Image | Product | Details | |
|
US Forge 00202 Bronze |
Super stiff spring Heavy duty clamp Great contact surfaces |
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Hobart T-Style |
Made of brass Takes a large cable Cooler operating |
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Lincoln KH525 |
It's big Clamps tightly Copper contacts |
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Forney 54410 |
High quality Great value Heavy duty |
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KingQ Welding |
Opens wide Affordable Strong attachment |
Best Welding Ground Clamp with Reviews
Here's a list of the best welding ground clamps we found on the market:
1. US Forge 300amp Heavy Duty Bronze Welding Ground Clamp
- 300 amp rating
- Bronze material
- Oval-point set screw
- Very large cable diameter
- Bottom jaw 55 points of contact
Pros
- Strong spring
- Wide, grooved jaws
- Very rigid
- Bronze alloy
- Heavy duty construction
Cons
- Spring is too stiff for some hands
- A little pricey
Overview
This is a heavy bronze alloy clamp rated at 300 amps, which should be plenty to cover most welding applications. 200 amps will weld 1/2-inch steel, meaning this clamp is made for even thicker plate. The US Forge Heavy Duty Bronze Ground clamp is designed with oval-point cable connection screws for positive contact and secure connection of the ground cable. It uses a very large No. 1 ground cable for maximum conductivity. This clamp is cast with wide, heavily cleated jaws for great grip on the grounding surface.
The US Forge Heavy Duty Bronze Ground clamp is heavily praised by welders for its sturdy build and heavy, thick construction. It’s stoutly built for abuse and durability. The jaws have a sizable contact patch, and the amount of force in this spring is definitely going to give a good grip on the work piece.
For safety’s sake you need a great connection through the ground clamp. Many users complained the spring on the US Forge Heavy Duty Bronze Ground clamp is too stiff. This could be an issue if you have an injury or you’re small-statured.
2. Hobart T-Style 400amp Brass Ground Clamp
- 400 amp capacity
- Brass construction
- Heavy duty design
- Stabilizer for cable
- Large set screw
Pros
- Very stiff spring
- 1-1/2 inch opening
- Takes No 1 cable
- Rugged replacement
- Cast instead of stamped
Cons
- Some alignment issues
- Inconsistent contact patch
Overview
The Hobart T-Style Ground Clamp is an industrial quality, professional grade piece, exactly what you would expect of the Hobart name. It’s cast from solid brass and it’s got the highest rating in this roundup at 400 amps. That’s more than most welding jobs except professional pipe layers, shipbuilders and the like.
Some owners complained of poor jaw alignment, something that could affect its gripping force. Because it’s made of brass, the Hobart T-Style Ground Clamp is relatively soft and can be bent out of alignment by rough treatment or improper storage. The flip side is that it’s relatively easy to straighten out as well. The high current rating delivers a cooler operating temperature. When a ground clamp has a very stiff spring like this one, it’s helpful when the clamp isn’t too hot when you have to grab it hard.
The Hobart T-Style Ground Clamp has some reports of casting imperfections in the contact area of the jaws. Sometimes the cleated lugs on the jaws have seams or casting flash that might need to be filed or ground away to provide maximum contact for the jaws.
3. Lincoln Electric KH525 300amp Ground Clamp
- Inexpensive solution
- 300 amp capability
- Heavy lug bolts
- Copper hardware
- Wide circuit braid
Pros
- Replaceable contacts
- Good warranty
- Takes No. 2 cabling
- Precision design
- Large opening
Cons
- Needs cable support
- Copper hardware is plated
Overview
One of the things that owners mention most often with the Lincoln Electric KH525 – 300amp grounding clamp is that it’s big. They also report that it’s got a very stiff spring, hard to grab for people with small hands or carpal tunnel syndrome. With an industry leader like Lincoln, you can usually expect tools that do their job well. This clamp is no exception, with nickel-plated steel construction and replaceable copper-plated hardware.
The Lincoln Electric KH525 comes with a one-year warranty, something not seen on other clamps. For a clamp in this price range, it’s a very high quality piece, with well-designed contact cleats for the jaws. It takes cable sizes from No. 2 up to a big No. 0, but it does need better cable support. Some owners use a zip tie, mechanical wire or a hose clamp to hold the cable rigidly to the clamp handle.
The good thing about such a big clamp is that the Lincoln Electric KH525 opens to 1-3/4 inches, allowing you to fit it onto difficult to ground items like axle housings, large bolts or suspension components.
4. Forney 54410 300amp Welding Ground Clamp
- Nickel plated steel
- Rated at 300 amps
- Jaw opens 1-3/4 inches
- Copper contact points
- Accepts No. 2 cable
Pros
- Stiff spring grips well
- Contacts workpiece securely
- Double nut lug connector
- Inexpensive
- High quality
Cons
- No cable brace
- Not for professional use
Overview
The Forney 54410 300 Amp steel ground clamp is a rugged economical ground clamp for shop maintenance and field work. Good positive connections for conductivity. Suitable for all farm and shop welders.
Forney Industries is one of America’s longest operating family-owned metal working product companies. Founded in 1932, Forney offers more than 5, 000 products for the hardware, automotive, farm and ranch and Do-It-Yourself markets.
8-Inch (203.2 mm) long with 1 3/4-inch (44.4 mm) wide jaw opening. Accepts up to no.2 welding cable. Claims for warranty must be made within 90 days of the date of purchase. Proof of purchase required.
This warranty does not cover any product that has been subject to misuse, neglect, negligence or accident, or that has been used in any way contrary to the purpose intended
5. KingQ 300amp Welding Ground Clamp
- 2-inch capacity
- 300-amp rating
- Brass construction
- Cleated clamping surface
- 8 inches long
Pros
- Inexpensive
- Strong clamp
- Long jaws
- Large No 1 cable
- Strong attachment lug
Cons
- Inconsistent quality
- Small contact patch
Overview
The KingQ Welding Ground Clamp is a 300 amp piece cast in bronze. While it is heavy duty and quite solid, there are reports of this clamp coming apart at the pivot point. This clamp has jaws that open widely to a full 2 inches. It’s designed to accept a No. 2 cable, which is pretty big for a bolt-style attaching lug.
This clamp does have a lot of reach and a good opening, but some owners do complain of a small contact patch on the KingQ Welding Ground Clamp when it’s clamped to the work. This is a function of the shape of the clamp. While it does have a solid, stiff clamping force, the small contact area limits its functionality somewhat.
For the price range, it’s our opinion there are better clamps on this list. If you’re in a bind, however and this is the clamp you have available, it’s heavy enough to take care of business, but the KingQ Welding Ground Clamp isn’t recommended for heavy volume in a professional environment. For a DIY workshop at home, it will work fine for occasional use.
Buyer’s Guide
The grounding clamp in an electrical welding circuit serves two purposes.
- It makes the welding process possible in the first place by completing the circuit through the workpiece.
- By completing the circuit through the workpiece, it keeps the circuit from completing itself through YOU.
Cable Size
To achieve a good ground, you need a large cable to carry the current to the clamp.
When you’re looking to go over 200 amps on occasion, you need a No. 2 cable or larger.
No. 0 isn’t out of the question when you’re approaching 250 amps.
Attachment Design
The most common design for heavy-duty clamps cast from brass or bronze uses a set screw that crushes the cable against a flat spot.
Others use a bolt drilled to accept the cable, squeezing it between two nuts or against the clamp body.
Of the two, the set screw design is usually the higher-quality method.
It’s also helpful if there is some method of supporting the inbound cable on the body of the clamp, such as a loop, tube, or tunnel to stabilize the cable so the soft copper doesn’t get overworked and give way.
Spring and Pivot
Clearly, in view of the fact that the clamp needs to be secure to provide a proper ground in order to keep you safe and provide a quality weld, you need a very stiff spring to grip the workpiece securely. You need to be able to squeeze the clamp, but if it’s too stiff it will wear out its pivot without a great deal of use.
Contact Patch and Jaw Width
You want a point of contact that provides a good grip and sufficient contact area to get the job done.
Conclusion
We feel the US Forge Welding Ground Clamp fills your needs the best overall, and at 300 amps it’s easily capable of most work done outside of a railyard or pipeline.
If you do work at a shipyard or at a mine, the Hobart T-Style Ground Clamp is the one for you, with a 400 amp rating and solid brass construction.
For beginners and home workshops, both the Lincoln Electric KH525 and the Forney 54410 Welding Ground Clamp are high quality, economical alternatives rated at 300 amps that will last a good while and keep you safe.
