There is no single process for gear manufacturing as they require different processes depending on the type and application.

Machining is one of the most common gear manufacturing processes due to its versatility. Traditional machining is fairly common in gear cutting and manufacturing, but advances in CNC machining have driven its popularity.

The following 4 gear cutting methods are the most common across the industry.

1. Broaching

Broaching is perhaps the fastest cutting method for gear formation. It relies on multi-tooth cutters with inserts that are deeper than previous generation cutters. This allows for smaller incremental cuts that are easier to perform and quickly achieve the desired shape without compromising precision.

This gear manufacturing process is typical for internal gears, but you can also use it to make external gears. For this, you need a specialized tool for pot broaching that allows you to replicate the same precision and efficiency.

2. Hobbing

Gear hobbing machines use conical cutting devices called hobs. As the hob rotates around the gear blank, both the hob and the workpiece turn. So far, external spur and helical gears are the only products that can be manufactured by hobbing.

The process is very versatile and fast. You can also increase productivity by working on multiple stacks at the same time. However, it requires more skill and precision.

3. Forming

Gear shaping is an advanced gear cutting and manufacturing process that creates gears that hobbing cannot handle. The cutter can be any shape such as pinion, rack shape or single point shape. It looks very similar to a gear and works by cutting a blank into the shape you need. You can create internal or cluster gears through the forming process.

4. Milling

This is a basic gear cutting method where you produce individual gear teeth sequentially. However, it is very versatile, especially if you are working with a CNC mill. While you can make any type of gear on a milling machine, the precision of this method leaves a lot to be desired. That's why milling is not as common as it used to be.

However, recent developments in the field of CNC and multi-axis have changed everything. Gear manufacturing on milling machines is becoming more and more common. So, things get better over time.

Post-manufacturing of gears

Depending on the gear manufacturing method you used, your gear will need some post-processing before it is 100% ready. Post-processing ranges from heat treatment to improve fatigue properties to dimensional correction and surface finishing.

Top 5 most common surface finishing processes in gear production.

1. Grinding: Grinding, as the name implies, is a common surface finishing process that smoothes an entire surface. You can do it intermittently or continuously without affecting the results.

2. Lapping: This process is suitable for sensitive gears that require extreme precision. Lapping uses small abrasive particles to smooth the surface at low or medium speeds.

3. Honing: This is another common process that polishes the surface and makes it smooth. In addition, you can correct some minor errors in tooth geometry.

4. Shaving: This process removes extremely thin layers from the surface for a smooth contour. Shaving is usually expensive, so it is rarely used in gear production.

5. Polishing: Essentially, polishing is the process of using compression to smooth a surface.

Gear manufacturing is a highly specialized field that requires extreme precision and accuracy. Gears are an essential part of any mechanical system, and even the smallest manufacturing flaw can have many disastrous consequences. Therefore, you need to choose the service you choose carefully.