4 Large Sheet Metal Shear Defects and How to Avoid Them

Shearing is one of the unavoidable operations in the metal fabrication industry and helps to trim and remove unwanted material from sheet metal quickly and efficiently. This is a common process performed in all metal fabrication shops to precisely cut sheet metal, plate, and tube to the required specifications. While this process doesn't cause any burning or melting, it can cause quite a few defects in the workpiece. Here at Hengli, you can find quality sheet metal shearing tools and equipment. This article discusses some common cutting mistakes and ways to avoid them.

Below are some common shearing mistakes that metal fabrication professionals tend to make during machining. This section also provides insights on how to eliminate shear defects.

1. Edge Deformation: Edge deformation, is one of the common metal shearing defects, and is caused by incorrect blade shear clearance, damaged blade, or improper downward pressure. To prevent such failures, the operator should ensure that the blade clearance is set correctly according to the specifications of the metal being cut, while also confirming that the clamps are holding the material properly in place. Also, the sharpness of the blade must be checked.

2. Twisting: One of the reasons behind this metal shear failure is twisting the plate along its axis, which causes the pieces to twist into a scroll or spin. Excessive rake angles can also cause twisting. To avoid such errors, the operator must adjust the rake angle according to the sheet metal geometry, material properties, and cutting parameters.

3. Bending: If you observe that the edge of the workpiece rises slightly from the plane, this may be caused by improper shearing of the metal. It is a common metal shear failure called buckling. Thin, narrow metal strips bend downward more easily. To reduce this effect, it is recommended to reduce the front angle to a minimum, while securing the metal plate with back support.

4. Arching: Arching occurs when the thickness of the sheet varies with width. This defect occurs when the workpiece is moved horizontally without twisting, resulting in convex, concave, and triangular material. As one of the common shear errors, operators try to minimize it early on by changing the grain orientation of the material and adjusting the rake angle of the workpiece.

Even though the shearing process can cause several of the aforementioned flaws, it's still the most important option for cleaner cuts and straighter edges. It also produces minimal or no cuts and allows you to cut small sections of material at a time without splintering, burning, or melting the material. While common clipping mistakes can be easily avoided, here are some recommended methods that will ensure the best end result.

1. Know Your Machine: Most importantly, the operator must take the time to understand the function, design, and operation of the machine before using it. Read the user guide carefully and understand the maximum allowable capacity and warning signs. Make sure to protect the machine with the proper lubricants and fluids as recommended by the manufacturer.

2. Periodic Inspection: Sheet metal shears are subjected to harsh use in industrial equipment. Therefore, regular inspections are necessary to prevent downtime. Carefully inspect the machine for any damage, wear, and lack of lubrication. Also, make sure that safety mechanisms are properly in place to avoid unforeseen accidents. Documenting such inspections is also mandatory for two main reasons; preparing a preventive maintenance schedule and starting repairs immediately.

3. Check the Blade: The key to the best-cut quality is to set the blade correctly according to the workpiece specifications. Make sure to check the sharpness and clearance of the blades before starting each cutting process.

4. Repair Immediately: If you find any abnormal working pattern, please do not run the machine. Stop immediately and inspect the machine. Minor troubleshooting; or calling in experts quickly to prevent catastrophic failure.

By following the steps above, you can eliminate shear defects that are common in metal fabrication shops. Also, it is recommended that you source your shears from a trusted manufacturer such as Hengli. With high-quality metalworking tools and machines like these sourced from experts in the field, you can be sure to cut sheet metal with great precision, hassle-free, and hassle-free. If you plan to purchase sheet metal shearing equipment, please contact us.

Hengli is a professional sheet metal shearing equipment manufacturer. Our company's R&D department is a national and provincial scientific research project such as Zhejiang's key technological innovation, provincial key high-tech products, etc. Our company also has more than 10 innovation patents and nearly 30 utility creation patents. As one of the national industry standard-setting members, we have core technologies and core products with independent intellectual property rights.