When cutting sheet metal whether by guillotine, CNC punching, CNC laser cutting or with press tools there will be some evidence of the cutting process which is known as a burr. Sometimes these burrs can be left in place and are not important to a component’s final operation, they may be internal parts that will not be handled by the final customer or parts that will be powder coated and have the burrs ‘softened’. If the burr has to be removed or de-burred then there are a range of processes that can be employed to achieve this.
Small sheet metal components can be de-burred in a barrel which is called barrel de-burring or rumbling. The components are put into a barrel with small ceramic stones and allowed to roll against each other to remove the sharp edges on the outer profile and around any holes and cut outs that have been pierced. This process is particularly suited to parts that are to be treated in someway e.g. zinc plating or powder coating as the barrelling process will remove any protective surface finish already on the sheet e.g. galvatite or zintec.
Sheet metal components that need to have the outer edges de-burred but the surface untouched need to be edge de-burred. These parts are best de-burred on vertical belt de-burring machines. Parts that have to be anodised, zinc plated or left self colour fall into this category. The sheet metal component is moved across the rotating belt to remove the burrs. The process is quick and effective on most materials and gauges. The nibble marks that can be left by CNC punching can be removed using this process as well as removing any slag that may be left on the cut edges after laser cutting.
As well as edge de-burring sheet metal fabrications need to be cleaned up after welding to produce clean joints. The purpose of cleaning up the welds may be to improve the fit of components in assembly e.g. allowing a welded lid to fit cleanly over a welded box base. The cleaning up may be purely cosmetic to hid the welding process once a component has been painted. The tools used to clean up welds can range from grinding disks, hand held de-burring belts and orbital de-burrers. Using a range of grinding grits a surface can be made as smooth as the original parent sheet metal.
If a better cosmetic finish is required such as replacing the grain on stainless steel after welding or polishing a surface to a mirror then we can sub-contract these processes and produce very high quality components.