Power
The total power of the router, more precisely, the engine installed in it. The
higher this indicator, the more productive the device is, the better it copes with complex work, the more force on the cutter (torque) it provides during operation, and the greater the spindle speed can be (although a powerful tool is not necessarily high-speed). On the other hand, high power significantly affects the dimensions, weight and price of the tool, plus power consumption and network load increase accordingly. In addition, high torque in some cases (for example, with delicate processing) is frankly undesirable. Therefore, a tool should be chosen according to this parameter, taking into account the real needs and the specifics of the planned work.
There are three main categories of milling cutters in terms of power: light (up to 700 W), designed mainly for simple household work; medium (up to 1500 W), able to cope not only with domestic, but also with most professional tasks; and heavy (1500 W or more), used in cases where high power is critical. However, this gradation is true only for routers (see "Type"), other varieties have their own specifics: for example, lamellar models, in principle, do not need high power.
Max. cutter diameter
The largest diameter of the cutter that can be installed in the router.
The larger the cutter, the faster its cutting edge moves and the more material it can capture, but larger nozzles require more torque. Accordingly, the maximum diameter of the cutter is directly related to the power of the tool (see above): the larger the allowable size of the nozzle, the more powerful and advanced, usually, the router is. However, large cutters (as, in fact, high power) are not always really needed. Therefore, when choosing according to this parameter, it is worthwhile to adequately evaluate the upcoming work and not chase the maximum size.
Max. groove depth
The greatest depth of grooves or holes that the router can make. This parameter is relevant only for lamellar and filler models (see "Type") — in other varieties, such a parameter as the stroke value has a similar value (see below). In most cases, the maximum groove depth does not exceed 30 mm — this is quite enough to use the lamellar / filler router for its intended purpose. In some professional models, this figure can reach 70 mm, but this is very rare.
Noise level
The noise level produced by the router during operation. This parameter is quite approximate, since the actual “loudness” depends not only on the characteristics of the tool itself, but also on the material and shape of the workpiece being processed, the type of cutter, the speed of work, etc. Therefore, in fact, the noise level may differ both up and down; in the characteristics, a certain average value is given, by which, however, it is quite worthwhile to navigate.
The “quieter” the tool, the more comfortable it will be to work with it, the less likely it is that the operator will need protective headphones. At the same time, we note that routers, by definition, are quite noisy — the most “quiet” models give out about 75 dB. Also, keep in mind that the decibel is a non-linear quantity, so it is best to use comparison tables when estimating the noise level.
Here is a simplified version of such a table for the range in which most modern routers operate:
75 dB — scream, loud laughter at a distance of 1 m;
80 dB — motorcycle engine, mechanical alarm at the same distance;
85 dB — a loud cry at the same distance;
90 dB — demolition hammer at a distance of 1 m, a freight car at a distance of 7 – 10 m;
95 dB — subway car (inside or at a distance of about 7 m).
