Wood is simply an amazing material. As it is a living, organic material, there are an infinite variety of woods and characteristics. We will talk a little about using wood with your CNC machine here.
General recommended starting feeds and speeds for 1/8″ 2 flute flat end mills. Please start with these settings and adjust, these are not hard and fast speeds.
One thing to note about wood is that it can burn if:
You are cutting too slowly or your spindle speed is too high
Sawdust is getting stuck in your cut
You are using bits that are not designed for cutting wood
Softwoods (pine, fir, spruce, cedar…)
Most common softwoods tend to be more fibrous than hardwoods. This can leave strands and burrs (fuzz) on some cut edges. You can reduce this by adding a finishing pass in your program. You may also find either conventional or climb milling affects your cut quality as well.
Watch for warping, as many softwoods are more prone to warping.
Hardwoods (maple, cherry, oak, walnut…)
Most common hardwoods are more prone to burning, as the sawdust for these woods tends to be finer and stickier. You can reduce this by increasing your feed rate and decreasing your stepdown.
There are many grades of plywood. Most lower grade plywood can be cut quite quickly as the wood is quite soft. Higher grade such as marine grade and baltic birch is harder and may need reduced feeds and speeds.
Plywood can splinter and tear along the top cut edges. A downcut bit can be used to mitigate this.
Plywood uses glues that can affect your cut quality and may affect the longevity of your bits. Make sure to check and ensure that they are clean between cuts.
MDF is a cheap, easy to cut material that tends to cut quite cleanly and evenly on the CNC router.
MDF dust is incredibly fine and can be dangerous. Make sure to use appropriate dust collection and a mask. A using a dust shoe is a good option.
Like plywood, MDF also has chemicals and glues in the material. Make sure to check and ensure that they are clean between cuts.