FABtotum Personal Fabricator, Руководство пользователя

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FABtotum Complete Manual
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The ability to change the routers’ RPM is essential to good bit life and a good finish.
Vibrations should also be kept at bay. The fewer the flutes, the larger the vibration on the tool, as the load is always
localized instead of being distributed among more flutes.
If the tool is going too fast it will heat very quickly, increasing wear and may break. The added stress may ruin the motor
spindle.
But how fast is too fast? The concept is better described with the concept of Chip Load.
Chip Load is commonly referred as the amount of material each tool can remove from the stock. Chip Load is dependent
upon the feed rate, rotational speed and number of flutes. Each type of material will have a range of optimal chip loads.
If the speed at which the tool is proceeding in the material is too much considering the speed at which the tool is removing
material then the chip load is too high.
If the chip load is too high noise and vibrations will increase and this usually leads to damages to the endbit.
This leads to the concept of cutting depth. Since you can determine the cutting depth at which the tool operates, a deeper
cut will increase the chip load, while a more shallow cut will reduce the chip load. But a shallow cut will stress the tip of
the tool more, reducing its capability to plunge effectively in to the material in its lifecycle.
A finishing pass does require more passes to get a smoother surface. flat endmills are usually used only in roughing
operations while ball nose cutters are used for finishing contours so you get less of a jagged appearance as shown in the
diagram above.
MILLING BITS