Wooden pattern Maker in India | Ahmedabad

The most common version of the straight router bit is a straight-fluted bit. This comes with either one cutting edge (single flute) or two parallel cutting edges (two flutes) that will do an acceptable job on most cutting tasks. Straight-flute bits with one cutting edge are the only bits that come in very small sizes for routing inlays or other small jobs (there isn't much room on a 1/16 bit for two flutes). In larger sizes, this design cuts faster but with a slightly rougher quality than with other style bits. Wooden pattern Maker in India, Wooden pattern Maker in Ahmedabad

Those with two cutting edges are ideal for cutting rabbets or dadoes on the edge of a board, or for through-cuts in the center of a board, where the bit is entering and exiting the workpiece as it cuts. They are also a good choice for shallow mortises, such as hinge mortises, where you increase the depth of cut slightly with each pass. However, straight-flute bits don't plunge straight down into wood very well because the cutting edges are on the side, not the bottom. 

If you need to plunge straight down into a workpiece, such as when cutting mortises or stopped dadoes, you have two choices, either a straight-flute bit with an added point on the bottom, or a bit with cutting edges on the end that extend to the center of the bit. The former is a specialty item, often with an angled tip like a drill bit. The latter is usually found on spiral-flute bits.

In addition to being ideal for plunge cuts, spiral-flute bits (also known as shearing bits) leave high-quality surfaces. They are available with the cutting edge on the upcut and downcut. Spiral upcut bits tend to tear out a bit more on the top surface, since they are lifting the wood, but usually leave the bottom surface in excellent shape. The reverse is true for spiral downcut bits. A third style, known as a compression bit, is designed to cut the top and bottom edges cleanly--a plus for routing the edges of difficult plywood, for example. Wooden pattern Maker in India, Wooden pattern Maker in Ahmedabad

Spiral upcut bits often are used for mortising, because they clear the wood chips better than straight-flute bits. There is a tendency to tear out at the ends of the cut, but this is not usually a major issue. Because of the complex machining processes used to make spiral-flute bits, they cost more than straight-flute bits.

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