Welding, by design, is meant to join two pieces of metal in a permanent bond that, in many cases, is stronger than the two pieces of metal the weld joins. Breaking a weld without a grinder poses a lot of challenges. Managing to break a weld without a grinder can be arduous and may ultimately render the two pieces of metal unusable.
How to break a weld without a grinder? It is possible to break a weld without a grinder. In the welding and fabricating industry, methods of breaking welds without a grinder include:
- Using an oxy-acetylene torch
- Punching the weld using an arc or stick welder
- Gouging with a Plasma Torch
- Mechanical methods (hammers, chisels and other manual metalworking tools)
- Physically breaking the weld
Oxy-fuel torches tend to be workhorse around the metal shop. Not only can they cut and weld, but they can also be used to perform a variety of other tasks, including breaking welds. There are several methods of using an oxy-fuel torch to break welds.
Since most shops employ oxy-acetylene torches, the methods of breaking welds that use the gas combination are the focus. Other gas fuel combinations will work but may require different equipment and settings.
Flame or torch gouging is a method of using an oxy-acetylene torch to remove metal. There are many good reasons to employ this method, not the least of which is how much quieter than a grinder it is. Flame gouging is also much quicker than cold chipping at welds.
Any oxy-acetylene torch rig works to flame gouge if equipped with the proper tip, and you use the right techniques. Flame gouging supply larger amounts of oxygen to the end of the torch than normal cutting or welding tips.
Proper flame gouging techniques heat the steel to a temperature above 900 deg. C or about 1650 deg. F. At this temperature, the addition of more oxygen to the torch causes the metal to melt. The pressure of the jet at the end of the torch pushes the molten metal and slag away. Unlike oxy-acetylene cutting, the molten metal and slag stay on top of the work instead of being blown through the work.
One of the downsides of the gouging method is the amount of oxygen required to accomplish the task. Some tips require flow rates up to 300 liters/minutes of gas. (App. 10.5 cubic feet/minute of gas). For small shop owners or home and hobby metal workers, keeping oxygen bottles full can get expensive.
The technique of flame gouging with an oxy-acetylene torch is a skill that may take some time to master. Not only does the torch have to be properly adjusted, but the speed with which the torch moves over the area and the angle at which the torch to the gouge is critical to producing a clean gouge.
Take care when using the flame gouging method to try and break a weld. You are heating the metal to a very high temperature, which will induce internal stresses. Just as they do when welding, these internal stresses in localized areas can cause the metal to buckle and distort.
Remember that you are heating the metal and moving molten metal. There will be splatter, which can become a hazard. Also, you are removing metal from both pieces of the workpiece. The now missing metal may affect the piece’s usability after breaking the weld.
Oxy-acetylene torches excel at cutting metal. A weld is metal, and an oxy-acetylene torch should cut it as easily as it does the metal that is joined by the weld, but that is not always the case. Understanding how an oxy-acetylene torch cuts metal is key to understanding how the problems associated with cutting welds.
When using an oxy-acetylene torch to cut metal, the acetylene flame heats the metal to its kindling point. At this temperature, the oxygen valve on the torch opens, sending a stream of oxygen onto the hot metal which oxidizes and blows through the cut as slag.
Most welds that join two pieces of metal are made by heating the two pieces of metal along the joint using either a torch or an electric arc and introducing extra metal in the form of a welding rod. In most instances, the addition of this extra metal creates a weld that is stronger than the two metals joined by the weld.
Cutting an existing weld is no different than cutting metal. Understanding the difference in the metal characteristics of the weld and the metal is a must. There must be a place for the molten slag to escape, so in most instances, you cannot cut into a weld unless you can be sure that you are making an opening on the other side of the metal.
Trying to break a surface weld and keep the bottom piece of metal intact is almost impossible using an oxy-acetylene cutting torch. To be successful, the lower piece of metal will have to be perforated or cut to allow the slag a way to escape.
Using an oxy-acetylene cutting torch to break welds can be efficient and effective used at the right time and under the right circumstances. Like any other process that heats the metal to high temperatures in a localized area, cutting with an oxy-acetylene torch induces stressed to the metal that can result in warps, bends, and twists.
The cutting process is destructive. Metal is given up at the point the cut is made and may render the metal unusable after the weld breaking process. Additional work to the remaining edges is also need to remove any weld material left and to clean the edges before making any further use of the metal.
Arc Welders: Using Air-Arc Welding to Break a Weld
Arc welders are used to remove metal as well as join metal. In a process called air carbon-arc welding, the intense heat of the arc created at the tip of the electrode melts the metals, and a compressed air stream blows the molten metal away.
Air-arc welding requires a special welding rig that has a nozzle attached to the jaw holding the electrode. The air is directed toward the weld and is controlled at the handle by the operator. The air connection does require a compressor with sufficient volume to feed the necessary flow rate.
The most crucial aspect of successfully using an air-arc to break or remove a weld is the selection of proper welding rods (and the condition of the welding rods). Welding rods come in three different types.
- AC Coated rods are for use with AC power sources.
- DC plain rods and DC Coated rods used with DC welders.
The choice for air-arc gouging is copper coated DC rods. These rods have a long life and low electrical resistance. The copper-coated rods come in a variety of shapes and sizes that allow several types of gouges using an air-arc welder.
The torch is another crucial set of equipment specialized for this type of welding or gouging. Torches come with single or dual air jets and boots that make hook easier and quicker. Always be sure that the cables meet the amperage requirements and that the air hose is properly connected and protected.
Air-arc gouging needs an airflow of about 27lbs or more. The need for a relatively large shop air compressor can be an added expense to set up an air-arc gouging rig. The noise created by the arc welding itself and the air-compressor running can be deafening in a small shop.
Once you have the right equipment, you can get started on breaking the weld.
- To effectively gouge with an air-arc welder, strike an arc on the workpiece and move it slowly forward. You may need to add some side to side motion depending on the width of the gouge you need to make to remove the weld.
- Once the arc starts, don’t hesitate. Keep the electrode moving forward.
- Hold the electrode so that it slopes back away from the work direction. Direct the air jet past the tip of the electrode. You should see the molten metal being blown away from the arc as you work.
- Keep the electrode at a 35 to 45-degree arc as you push it forward along the line of the gouge.
As with gas torch gouging, the speed of the tip of the electrode controls the depth of the gouge. It is important to maintain as short of an arc as possible. Maintaining a short arc can be a challenge as you are both moving the electrode forward and the arc is consuming the electrode as the gouge forms.
Air-arc gouging to remove welds probably requires more skill than using a gas torch to perform the same job. The combination of moving and maintaining a position can be challenging. However, the results can be as good if not better than gouges produced with a gas torch.
Air-arc gouging, like gas torch gouging, is a destructive process. It uses the same sort of temperatures localized in relatively small areas. You are losing metal and can potentially induce stresses that will render the workpiece unusable after the weld removal.
Plasma torches are relatively new beasts to the welding world. They have developed a reputation as a quick and clean way to make precise cuts in metal. Plasma cutters are now available at a price that brings them into the range of hobby and home metalworkers.
Plasma cutters operate by creating an area of superheated electrically energized ionized gas, commonly known as plasma, and focusing this plasma with a blast of some gas agent though the orifice of a nozzle at the material.
Plasma cutters are a very advanced form of air-arc welding. Inside the gas stream, an arc forms in the plasma and passes from the gas nozzle to the workpiece. The gas jet then blasts the molten metal away from the arc, creating the cut.
In plasma cutters, the nozzle is a disposal part of the process, burning away as the arc forms between the nozzle and the workpiece.
Using plasma cutters to gouge metals is just like using gas torches or air-arc welders. The theory is the same, and the practices are the same. Unfortunately, there isn’t much solid information about how to use a plasma cutter for weld gouging.
At this point, the methods and techniques of using a plasma cutter to gouge in metal is a free for all. Everyone who does it has their own set of instructions and advice. One website likens the situation to the “wild west of welding.”
What Do You Need to Gouge With a Plasma Cutter
You need a plasma cutter. While the prices of the smaller units have come down in the past few years they remain relatively pricey and maybe beyond the budget of most hobby metalworkers. If you can afford to put one in your shop you will need all the appropriate safety gear.
More than anything, you need to practice. Just like with gas torch gouging or air-arc gouging, some elements require time to master successfully. Speed, power, and angle of attack are the keys. There isn’t much data or information in the literature to be helpful as there is with the other two methods of gouging metal.
Learning to judge speed and angle of attack as you begin the process is an acquired skill. It takes time to build these kinds of skills and if you want proficiency with the tool, you must put in the time.
One upside to deciding to add a plasma cutter to your shop is the availability of the tool for its intended job. Cutting metal with a plasma cutter, once you master the skill, is easier, faster , and much more satisfying than any other method.
Mechanical breaking welds while theoretically possible, is not optimal. A properly done weld is usually stronger than the metal that it joins. Using mechanical forces to break such a bond will more than likely distort, bend and destroy the adjoining metal.
A cape chisel might, on small short welds or tack welds, effectively break the weld. On longer deeper penetrating welds, the time and energy needed to drift a chisel deep enough into the weld to break the joined pieces of metal are probably not worth the effort.
Welding literature mentions using a diamond point chisel. A diamond point chisel might also be possible, but again the energy and effort that would go into such a project would hardly be efficient. Unless you are very proficient at sharpening chisels for this particular purpose, your efforts would probably come to a halt quickly.
Should you manage to break a well-executed weld, the result would be less than acceptable. Chisel marks, ragged cuts, and edges, tears in the metal, and hammer marks on the joined pieces of metal would result. Again, the outcome will be workpieces that are unacceptable for any project.
Physically Breaking the Weld
Frustration can often lead to desperation and some metal fabricators, frustrated by a stubborn weld that refuses to budge, often turn to desperate measures. Physically distorting a weld to the point of failure is an option. Some laboratories do this on a routine basis to check the quality of welds.
The laboratories doing this testing to failure use sophisticated machines that measure forces acting on the metals to determine how well the weld has fused the two pieces of metal. Fabricators, in desperation, often turn to the largest hammer they can find to try and break a weld.
More often than not, the result is a piece of bent, twisted and useless metal with a weld that shows hardly any deformation or change. It isn’t that a weld won’t break in this way. The fact that most welds are stronger than the metals they join means that the metals will suffer more damage than the welds in this kind of process.
Just like mechanical methods of breaking welds, physically breaking welds is not an option.
Can You Break A Weld Without A Grinder?
Technically yes. The most effective method of removing a properly applied weld is to gouge the weld using an oxy-acetylene or air-arc torch. Even then, the results will be less than satisfactory and require additional work to make the previously joined metals useable.
Most professional welders will tell you that the better option is to move to the side of the weld and cut through the metal away from the weld and scrap the area of the weld. Removing the weld in this way may cost you some dimension on the metal, but is easier and opens the option of other tools, such as reciprocating saws.
The better answer to this question is that there are better ways to approach the problem than breaking a weld.
There are no impossible tasks, only those that take longer and cost more. It is up to you to weigh the cost in time and effort against what you hope to accomplish. That is especially true when breaking welds.
The methods presented here will certainly work. How well they work and whether they produce satisfactory results is not guaranteed.
When some other methods and tools specifically designed to do a job are available, the question becomes, “Why would you not use the tool designed for the job.” By and large, using a grinder will make the task of breaking a weld easier, less frustrating, and more efficient.