Love creating hifi equipment
Joined 2023
Paid Member
To make the explanation easier to understand, I drew a simple force analysis diagram.
Since the largest number of players use fulcrum tonearms with fixed rotation points, the analysis in this article only focuses on this type of tonearm.
The cause of the side skating force is shown in Figure 1. When the record rotates, it rubs the needle tip of the record to generate friction. This force is the tensile force F1 acting on the tone arm in the tangential direction of the arc of the record due to the design of the tone arm compensation angle. The tangential pulling force F1 and the tone arm pulling force F2 are not on the same straight line, so the resultant force F3 of F1 and F2 is generated, which we call the side skating force for short. (The accompanying pictures are drawn at random, for demonstration purposes only, and the sizes and angles are not completely standard)
Based on the physical law that the greater the pressure, the greater the friction. The greater the needle pressure, the greater F1, the greater the tone arm pulling force F2 back, and the greater the side skating force F3.
In order to avoid the adverse effects of side skating force, many tone arms produced later will have an anti-side slip structure added to the axis of rotation of the tone arm. Some of these structures use suspended micro-weights, some use spring-like structures, and so on (Figure 2-5 is an example of various common anti-sideslip structures). In short, it is all to add a reverse force to offset the side skating force generated during playback as much as possible.
But the side skating force is not constant during playback. During the playback process from the outer ring to the inner ring, the change curve of the sideskating force is a bit close to an inverted parabola. The side skating force is maximum when the outer ring radius is about 150cm. It first slowly decreases when playing inward, and is the smallest at about 80cm in the middle radius. Then it slowly increases when playing inward until it reaches the innermost ring radius of 50cm. There has been an increasing trend in the process, but the side skating force of the innermost ring is still smaller than that of the outermost ring at 150cm.
There are many factors that affect the change of sideskating force, such as the degree of cleanliness in the sound pattern, the degree of balance adjustment of the turntable, etc. Even needle tips with different shapes produce different side skating forces under the same needle pressure. Like Shibata needle points, linear needle points produce greater side skating force than ordinary elliptical needle points.
Last edited by a moderator:
Seems like every thread you start is trying to reinvent the wheel.
Nothing new here, that hasn´t been common knowledge since the 50`s.
Same with the "Keep your needle clean-thread" and a lot of others.
Nothing new here, that hasn´t been common knowledge since the 50`s.
Same with the "Keep your needle clean-thread" and a lot of others.
Nice explanation 🙂
It's pure commercial spam / clickbait stuff with some copy paste from a 'technical' paper or website.
Even worse, It pretends to educate or share knowledge but only annoys and polutes the forums.
It's a very dirty way of promoting one's commercial interests!
Hugo
