Every piece of machinery is made up of a thousand smaller pieces all continuously working together to accomplish the same goal. Every single one of these pieces need to go through the part finishing process, which ensures they work correctly and keep the overall operation running smoothly. “Part finishing” is an umbrella term for all the individual processes and techniques that go into the ultimate completion of these parts/gears.
Machining
First, let’s start with machining. This is where gears/parts are initially manufactured out of blocks of raw material. CNC (computer numerical control) machines do most of this work, and there are multiple different kinds of CNC machines, such as milling machines, lathes and turning machines, laser cutting machines, etc. Excess material is carved away by these machines to reveal the rough shape of whatever gear/prismatic part is being created. Once this first step is completed, the nitty-gritty side of part finishing begins.
Deburring
Deburring is the process of removing burrs from the edges and surfaces of these freshly cut parts/gears. Burrs are sharp bits of excess metal that will eventually ruin the integrity and overall quality of whatever part/gear they’re stuck to. This process can be done by hand, in a CNC machine, or a machine made specifically for deburring*, such as a James Engineering machine. Deburring is one of the most crucial aspects of part finishing, as many other processes cannot be done if a part or gear is not deburred properly.
Surface Grinding
This process creates smooth surface finishes on metal and non-metal parts alike. It’s an abrasive process which uses grinding wheels to shave down any surface impurities that might affect the functionality and aesthetic of a gear/part. Grinding wheels (add link to website page here) come in a variety of sizes and materials, which directly determine a wheel’s grinding intensity. Grinding surfaces are crucial when it comes to achieving tight part tolerances, as it ensures a part will fit perfectly within its environment. Surface grinding will also rid a part/gear of any corrosive layers that may negatively affect its overall durability.
Polishing
Polishing is done to further smoothen a part’s surface. What makes polishing different from surface grinding is that it’s meant to enhance surface quality, whereas grinding is used to remove extra material. Polishing is also an abrasive process, and it uses polishing pastes and abrasive pads. Polished parts are reflective and more resistant to corrosion, which makes it a crucial step in the finishing process for items such as car bumpers, medical equipment, mirrors, and more.
Buffing
Many people get buffing and polishing confused—but it’s fair considering how alike these two processes are. What makes them different is their levels of aggression. Buffing is the more aggressive of the two, and can actually remove surface material if done too hard. It can be used to remove shallow scratches, and unlike polishing, it will not leave a highly reflective surface. Buffing is frequently used in the automotive, jewelry, and electronic industries.
Chamfering
This step of the part finishing process is extremely important, especially for pieces with right-angled edges. Chamfering is when these edges are cut at a slope, which later makes assembly easier and reduces the amount of stress risers within a gear/part. Sharp, non-chamfered edges can snap and break off, leading to loose material floating throughout a machine. This debris could ultimately affect the efficiency of the entire machine, and even cause it to fail completely. When edges are chamfered, the likelihood of such an occurrence is reduced drastically. It will also ensure that pieces fit together more snugly, reducing the risk of the parts themselves becoming too loose.
Brushing
Brushing can be categorized as a type of deburring, as it can technically get rid of excess burrs left on the surfaces of parts. But that’s not its man job—brushing is used as a way to further perfect part surfaces, as it preps parts for coatings and rids them of any external contaminants, such as oils, dirt, residue, etc. It is also a very precise process in the sense that if only one small section of a part/gear needs further surfacing, a brush can stay focused on that specific spot without affecting the rest of the gear/part’s body. An important thing to remember when it comes to metal brushing is that certain brushes must be used on certain metals; for example, stainless steel can only be brushed with steel brushes. But other materials, such as rubber and leather, can also be brushed if need be.
Sandblasting
This process is also known as abrasive blasting, as it can be done with many other substances other than sand, such as glass beads, water, dry ice, and compressed air. This is another technique used to smoothen, decontaminate, and shape surfaces. This technique of part finishing comes from the naturally occurring phenomenon called aeolian erosion, which is when an environment’s geography is changed and shaped by consistent winds. Blasting is done manually when a blasting substance is mixed with air in a pressurized chamber and dispensed through an abrasive-proof handheld nozzle.
Washing
The washing process works exactly how you’d think it would—a mixture of hot water, solvent, or washing fluid are dispensed either by hand or by a machine over freshly-processed parts to clean them of excess swarf. It’s important to wash parts of debris because, as mentioned above, debris can drastically decrease the effectiveness of a part/gear and the greater machine it was assembled into. In order to avoid corrosion or rusting, special fluids must be used to protect both the part being washed and the machine doing said washing.
Overall
Machining, deburring, chamfering, washing, brushing, surface grinding, polishing, buffing, and sandblasting are the most common part finishing processes in the manufacturing industry, but there are still a variety of methods used that were not mentioned. Each process has its own unique use, and it’s crucial that manufacturers understand what method will produce the strongest outcome for a part or gear.
How James Engineering Part Finishes
Here at James Engineering, we are experts when it comes to the varying methods of part finishing. We manufacture and sell all all-encompassing surface finishing and chamfering machine known as the MAX System, and it’s got you covered completely—the MAX can deburr, chamfer, wash, brush, and even radius parts/gears of various sizes. The best part is the MAX can carry out multiple processes at once, which exponentially cuts down on processing time and leads to a higher production volume.
If you’d like to experience the effortless efficiency of a multitasking finishing fiend, contact us at Sales@James-Engineering.com and we will send you a quote!
*For being such a vital part in the finishing process, deburring machines are an extremely niche market of their own. James Engineering specializes in deburring and chamfering machines and offers a variety of systems at competitive pricing. Click here to learn more about the different kind of systems we manufacture.