Is our crib suitable for the device?
The rocking device are suitable for all cribs with the longitudinal, transverse and universal pendulum. The pendulum must have ball bearings. In the case of crib with universal pendulum do not need to move the rocking device when changing the direction of swing of the crib. The device itself will determine the direction and will push the crib in the right direction.
The main condition for a good working of the device (in addition to correct installation) is low friction in the pendulum mechanism of the crib.
For estimating the friction in the pendulum mechanism move the crib from the equilibrium position at 4-5 cm and release it. Count the number of oscillations to almost complete stop when the amplitude of the oscillation (the distance between the extreme points) will be about 1 mm. You should count the number of oscillation periods; i.e., swung to the left-center-right-center-left - "one", center-right-center-left - "two", centre-right-centre-left - "three", etc. А good pendulum mechanism should have about 60-70 oscillations. Satisfactory result - at least 30-35 oscillations.
If the crib does less than 30 oscillations before stopping then necessary to find the cause of this. Perhaps the crib touches something during the swing - wall, the curtain. Perhaps something decreases the oscillations - for example, hanging on the back of the crib, heavy blanket, swinging in opposite phase to the crib.
If obvious causes are eliminated, but the bed still swinging bad, it is probably that in the pendulum mechanism of the crib increased friction presents.
The most common reason for this phenomenon - the plastic sleeve abutting to the inner bearing race. When assembling the crib due to excessive (and sometimes normal) tighten the mounting bolt they are often crushed and starts to abut, not only in the inner ring, but in the balls or even in the outer bearing ring.
The solution is to replace these bushings are normal M6 nuts. Between the inner bearing race and nut you also can pave the puck.
On the photos: (click to open in larger size) shows have already been converted bearing unit cot of production of company Kubanlesstroy (LEL), Krasnodar. Originally there were plastic sleeves. The entire alteration took about 10 minutes.
The result: before to alteration there was 12 free oscillations and after alteration there is 70 free oscillations.