Knocking clutch pedal

Last time I went out for a spin I noticed an ever so slight knocking, tapping feedback on the cluth pedal as I depress it. Today I went out and it seems worse and is just about audible.

Seems to go after the car is warmed up. Any ideas and will I have to raid the Christmas fund?

May be the clutch master cylinder spring breaking . Try depressing the pedal with your hand and see how quickly it returns.

Also check the clutch linkage, on the pedal.

There is a silly set up of a clip and 2 plastic washers that act as a bearing between the pedel and the linkage. These plastic washers go brittle, break and then the pedal acts directly on the pin, which begins to wear. You will then notice some free play in the clutch pedel.

by hand (but not when driving) move the clutch pedel back and forth and see where you have free play.

I think on my car the return spring is/has gone as the connecting rod does not return into the cylinder fully. I've yet to see how easy it is to get the cylinder off, to check the spring.

Thanks for suggestions. I'm pretty sure I've tracked it down to a thrust bearing. Had a look in the workshop manual, not too big a job?