CNC end Mills
Learn all the possible kind of cuts you can do with your CNC machine #
Straight Flute #
Largest flute space, it will carry most chips. Used for aluminum, and plastics and wood. Great for very precise edges and cuts.
Upcut and Downcut End Mills #
Up cut bits are very efficient at evacuating chips from the hole or slot it is cutting. This is especially important when the hole is ¼”-deep or more. Deep holes or grooves still have to be cut using multiple light cuts, but the upward direction of the flutes while rotating prevent the debris from building up in the hole and binding or even breaking the bit.
The problem with up cut bits is that the same action of the flutes that brings the chips up can also lift or fray the wood fibers around the edges of the cut. While this damage is usually minor, especially with good quality bits, it can be noticeable if those edges will be visible when the project is assembled.
Up cut bits are frequently used for cutting mortises because of their depth. Since the edges of a mortise are eventually hidden by the shoulders of the tenon that will be fit to it, this chipping or fraying will be hidden after assembly and have no impact on the finished project.
The downward slicing action of a down cut bit leaves a very clean, crisp edge around the hole or groove it cuts. While chips still are evacuated from the hole, a down cut bit is far less efficient in this respect than is an up cut design.
This chip ejection deficiency of down cut bits is minimized by the relatively shallow cuts they most commonly are used to make. Down cut spiral bits are a good choice for cutting dados or shallow grooves, especially when the edges will be visible when the project is assembled.
Down cut bits require a slightly slower feed rate. This reduced pace allows the bit a little more time to throw chips out and for them to be re cut into smaller pieces that eventually are thrown from the hole or slot.
Making shallow cuts to achieve the full depth needed is always important, but especially so with a down cut bit. The combination of a deep cut and a build up of chips can cause the bit to overheat and even break.
For most woodworkers, the down cut type of spiral bit is most useful, particularly for those using a router to cut dados, rabbets and visible slots. Some woodworkers like cutting mortises with a router, table mounted or hand-held. For them, the up cut bit will be most efficient.
The ideal situation is to have both types of spiral bits in the drawer, in the size or sizes you most often use. The quest for more tools certainly does not end with spiral router bits.
Up and down cut spiral bits are available in sizes ranging from ¼” to ½.” We used bits from Infinity Tools for this story, both ½”-diameter. The Infinity part numbers are, up cut bit – 85-913, the down cut bit – 85-914.
Ballnose Mill #
A ball nose end mill, also known as a spherical end mill or ball end mill, has a semisphere at the tool end. Ball nose end mills are used on workpieces with complex surfaces.
V-bit #
If you want to do lettering or detailed sign making, you’ll need to get a v bit. These are sometimes called v-carving bits, v-groove bits, or engraving bits. This is the only way to get a sharp grooved bottom on the inside of those roman numerals for your sundial. They are available in many sizes and angles. The most common and useful angles in order are 60deg, 90deg, and 30deg.
Compression #
Solid carbide compression spiral bits are designed for CNC applications requiring high feed rates and a clean finish. Particularly suitable for double sided melamine or laminated material. Choose single flute for the highest possible feed rate. The double flute provides a clean, smooth finish. Special unique carbide for longer lifetime in abrasive material.
Table-Surfacing #
These bits are used to surface your table quickly, giving a smooth and level work surface, ensuring accurate cut depths.