What is Slot Milling: Process, Types, Techniques & Applications

The process of machining is a diversified one and involves manufacturing shapes that are unique and have different geometries. Slot milling is also one of the machining methods used to create specific parts that have unique characteristics.

If you want to know what is slot milling and how it works, the guide below can help. So, let's read on.

What is Slot Milling?

Groove milling is another name for the slot milling process. It is a machining process in which the cutting tool rotates and creates a slot in the component. The slot can vary in terms of shape and size.

Step-by-Step Guide to the Slot Milling Process

The step-by-step process of slot milling has the following stages:

• The first stage is choosing the right milling cutter, which is chosen keeping the size of the slot, workpiece material, and the shape in mind. There are different types of mills that can be selected, like end mills, side or face cutters, and t-slot cutters. The chosen cutter must have the right diameter and length as well.
• Select the applicable cutting parameters like feed rate, depth of the cut, and the cutting speed. The cutting parameters impact the tool life, heat generation, and cutting forces.
• Clamp the workpiece in the milling machine tightly so that it doesn't produce any type of vibration at the time of milling.
• Place the cutting tool in a proper location with the center on the workpiece so that it can mill the slot of the workpiece properly.
• As soon as the position of the cutter is accurately set, start the process of milling by programming the CNC machine through the CAD program.
• The tool moves along the tool path and completes the slot features by machining them to the required finish, depth, and length. Adjust the depth of the cut if needed and ensure that the cutting process is properly controlled.
• After the process is completed, take the part out of the clamp and inspect it to match the required dimensions and tolerances.

Types of Slot Milling

There are different types of slot milling processes, and some of these are the following:

End Milling

End milling is carried out with a standard cutter or end mill, which offers versatile slots. These include close slots, even slots, and non-linear slots. The process is similar to face milling, and the cutting is carried out by the side as well as the face of the tool. There are different sizes and materials of end mills.

Side Milling

Side milling also helps to create slots in the workpiece by cutting the material through the tool periphery. It is a method of cutting that is stable and can handle the vibrations and cutting forces.

T-Slots

The T-slot cutting is a method that cuts the slots in a T-shape, and these are required mostly for the machining beds. They need a special T-slot milling cutter to create space for the T-slot milling cutter shank.

Woodruff Key Slotting

Woodruff key slotting is a method of slot milling in which the machining of the keyways is achieved. The designers can use the slot and key joints so that the parts can be locked with each other. The female part of this joint is created by the slot-cutting tool. The woodruff slot cutter can produce the keyword and lock the assembly.

Gang Milling

Gang milling is used for the parallel slots. It helps to mount the workpiece on the machine beds to achieve these slots during the process of milling. This process uses multi-groove cutters, which are mounted in a common arbor and have the ability to cut the slots at the same time. The process is time-saving and productive, but requires rigid machining tools.

Toolpath Techniques on Slot Milling

The different techniques for slot milling on the tool path are as follows:

Conventional

Conventional milling is the most simple tool path which is used in the process of slot milling. It creates straight cuts along the slot axis. The process is productive and easy when it comes to programming and is even compatible with maximum cutting tools.

The downside of the conventional toolpath technique is that it produces high vibrations when it comes to deep slots or materials that are hard to cut. The tool faces high radial forces, which adds a little instability to it and makes it prone to heat generation.

Plunging

Plunging is conducted when the entire slot is machined using the axial cuts; these consist of drilling in most cases, which is conducted through a milling cutter. It is used in setups where the tools are vulnerable to vibrations and tool deflections.

Plunging doesn't create slots with a good finish on the surface, and another cutter may be needed for the purpose of achieving the required surface finish.

Trochoidal

Trochoidal milling is a tool path that is a special type, and during the process, the tool follows the trochoidal path. The process is highly stable and gives cutting edges sufficient time to stay cool, and has enough span for the chip evacuation. It is also suitable for cutting materials that are hard, as it has a low average radial cutting force but needs complex programming.

Useful Tips for Optimal Slot Milling

When creating slots in the workpieces through the process of slot milling some of the tips to achieve the process optimally are the following:

• The tool and its coating should be compatible with the material that is machined so that the life of the tool is not compromised.
• The slot machining process needs chip evacuation, where you need to use coolants so that the chips do not cause any problems.
• Ensure engaging at least one cutting tool with the component so that the vibration is reduced and the surface finish of the slots is not compromised.
• To ensure stability, make sure to consider that your own milling also offers efficient chip evacuation.
• Balance the cutting feed rates so that the thermal issues are prevented, and the productivity is maintained.

Заключение

It is very crucial to understand the process of slot milling before you consider using it in your applications. The guide must have given you the relevant knowledge, and if you need to have the process carried out, make sure to get in touch with us at DEK. We can offer to create highly finished and neat slots in your parts, which you can opt to use in your projects.

Вопросы и ответы

Are CNC machines suitable for slot milling?

Yes, CNC milling machines offer suitability for slot milling in the workpiece.

What machines are used for slot milling?

Slot milling uses vertical and horizontal standard milling machines, and sometimes EDM and drilling machines are used.

What materials are commonly used for slot milling?

Slot milling is compatible with multiple types of materials, which include metals, wood, and even plastics.

What types of cutters are used for slot milling?

Slot milling uses multiple types of cutters, which consist of shell end mills, T-slot cutters, gang milling arbors, shoulder cutters, and woodruff key slotting tools.