CNC milling – End mills, speed and cooling

Medium Density Fiberboard, also known as MDF, is a synthetic product used for flat panels. It is normally used in various industries, especially carpentry and cabinetmaking, because it is a stable and uniform material. It can be produced in many different ways. An online machine shop can for example CNC mill MDF for you. After all, Medium Density Fiberboard can be machined easily with the help of CNC machining services as it is uniform and stable. On top of that, it can be finished to a high degree as well. Furthermore, MDF is quite cheap, which is why a lot of hobbyists use it to create furniture for example. If you are planning on using CNC milling to do this, you should really use the three tips mentioned below.

CNC milling machine – The end mill

An important part of a CNC milling machine is the endmill. You have to decide which one you are going to use, which you should do based on the material and geometry. When it comes to end mills’ material, usually the choice is between carbide and high-speed steel. Both materials can handle MDF rather easily, but usually carbide end mills are the preferred option when CNC milling wood. For its geometry, you can typically choose between down-cutting, straight flute, and up-cutting. Down-cutting end mills push the chips towards the material down the endmill, while straight flute end mills do not have any twist and are usually the cheapest option. Up-cutting end mills are extremely common and guide the chips away from the material and up the endmill.

CNC milling speed

However, the most essential aspects of CNC milling are speeds and feeds. This eventually determines the product’s surface quality, while they play a role in the rate of processing too, just like the length of tool life, the buildup of heat, and more. If the surface finish is important when CNC milling MDF, it is advised to use a high rotation speed of the spindle. This does mean that a lot of heat will be generated at the end mill. Therefore, it is required to use a higher feed rate too. By doing this, you can avoid an accumulation of heat, which is important since you can otherwise burn the MDF and destroy the endmill.f

Cooling and lubrication of a CNC machine

As mentioned before, CNC milling Medium Density Fiberboard generates heat. This can damage the material and/or the endmill. On top of that, sawdust build-up on the cutter and material will increase friction and limit heat convection, further increasing heat build-up. Since MDF is very sensitive to humidity, it is recommended not to use any type of liquid coolant during milling. Doing so can cause the MDF to swell and break, which can lead to a big mess. Furthermore, it can leave MDF sawdust everywhere in the room as well. However, you can use compressed air to clean and cool the endmill’s travel path. On top of that, a vacuum can be employed to remove unwanted debris during the CNC milling.