My little 'Sally the shaper' is a dinky little machine which on a good day is a joy to play with as she clicks, whirrs and scritches through the job.
Last night she threw a little tantrum! All was going well for several minutes then there would be a sickening thunk as the tool dug in and the machine stalled!

A dig in is bad news as everything gets rather strained and has to be reset plus if it happens near the end of the job the work might have to be biffed in the bin or a nasty gouge tolerated.
So I watched, and watched and of course nothing happened then I saw it. The clapper had managed to wear the pin out of round which meant after a hundred or so strokes the tool would not fall down and so one or two strokes followed cutting nothing but of course the feed was still advancing then when the tool finally did fall down the cut was about 3 or more time normal and hence the dig in.
A clean up and fixing the clapper pin took care of that!
Sally is a sweet little machine but she does like a little attention now and then!