How "slipping" clutch works to regulate takeup reel speed in cassette deck

[wasedadoc]

The "discs" on both sides of the felt pad spin.  One spins at constant rate determined by wherever the drive to them is coming from.  The one that slips, ie its rotation rate varies depending on how much tape is on the reel, passes drive to the take-up reel.

[MarkoGVA]

Thanks.
Does that mean that one disk is "fixed" to the axle and the other turns freely?

[shakalnokturn]

The one with the felt should not slip on the axle. The way I'd usually solve this when a nylon part isn't split to bits is to clean of any lubricant, lightly scratch the axis where the part should fit. Slide it into place removing any other part if possible, double check position, apply a drop of super-glue with the tip of a small flat screwdriver so that it fills the crack by capilaity. Not the neatest approach effective in most cases.
If take-up still isn't working after trying to adjust the clutch force, suspect that maybe the original spring was lost at one point.

[MarkoGVA]

Seemed to work fine for a while.
Now it is making this noise when it is idling
However, when I press play, the noise stops.
What could it be?

[MarkoGVA]

I guess it is difficult to know where the sound is coming from...