Rotation speed
The maximum speed of rotation of the working tool of the electric planer — a drum with knives attached to it. In modern models, this figure is practically never lower than 10,000 rpm (otherwise it is impossible to ensure normal quality of work), and in most cases it is in the range of 11,000 – 17,000 rpm. It is believed that the higher the number of revolutions, the more evenly the workpiece is processed and the smoother the surface is obtained; and the overall speed of work will be higher. On the other hand, a high speed also requires high engine power, especially when working with hardwoods; for such materials, it makes sense to use a low-speed tool — it will provide more efficient power distribution.
V-grooves
The number of V-grooves provided in the design of the tool.
V-shaped grooves are located on the sole of the tool in the longitudinal direction. They are used to chamfer the corners of the workpiece, serving as a kind of guide: the tool is “put on” by the groove on the corner being machined and moves along the workpiece so that the corner constantly maintains contact with the groove. It is much easier to keep the planer level with this way of working than with a solid flat sole; this is especially true in cases where the workpiece cannot be turned "angle up" and the planer has to be kept in an inclined position.
Also note that this function is intended only for the first pass along the corner, then you have to work in the classical way, with a flat sole — however, with a sufficient depth of the V-shaped groove, the chamfer can be removed immediately, in the first pass. Actually, this is the point of having several grooves in the design — in such cases they have different depths and can be useful for different chamfer sizes. The maximum number of grooves found in modern electric planers is
three ; using more in a hand tool just doesn't make sense.
Knives
The design of knives intended for use with a planer and, usually, supplied as standard. The type of knives does not affect the performance of the tool, but in the case of dullness or nicks, the methods for correcting the situation differ significantly.
— Unilateral. As the name suggests, these knives are sharpened on one side only. If defects appear on the blade, it can be removed and sharpened or the edge straightened. Technically, such an operation can be carried out many times, but it requires not only time, but also appropriate skills and equipment.
—
Bilateral. Knives sharpened on both sides are very convenient due to the fact that when the edge becomes dull or serrated, it is enough to remove the knife and install it on the other side, with a “fresh” blade. On the other hand, such blades do not allow sharpening — when the second side of the knife becomes unusable, the only option is to replace it.
Noise level
The maximum noise level produced by the planer during operation. The lower this indicator, the more comfortable the use of the tool, the less inconvenience it creates for both the user and others. Note that the noise level is measured in decibels, and this is not a linear unit — in other words, sounds with a difference of several dB in volume can differ significantly. A few examples for comparison: 75 dB noise is approximately equivalent to a scream, 80 dB is a motorcycle engine, 85 dB is a loud scream, 90 dB is the sound of a freight car moving at a distance of 5-6 m, 95 dB is the noise inside a subway car.
