More seriously I have today found the 'knock-off/clutch dog' is at present stuck/seized solid on the table leadscrew …

No rust – in fact quite oily.

Have removed the 2 tiny 1/8" Whit. (thought at first they were 5BA) CS screws and key (in case it had swarf jammed underneath) but still nothing moving. Another job on the list.

Explains why the knock-off lever had been hit with a spanner a fair few times and bent – and probably why the black knob was missing/shattered ?

Edited By Nigel Brown 7 on 08/02/2018 23:20:53

Solved !

Stripped down and removed table leadscrew/bushings/wormgear/table driveshaft.

Also removed gearbox cover to check internals.

'Knock-off dog' stuck very firmly because wear on the leadscrew (lefthand edge of Acme thread – mainly in the centre section) had led to a very slight raised burr. Because the dog to leadscrew clearance was minute, this was enough to jam the dog on the 'ridge'.

Eased the dog free with a copper hammer.

Dressed the burr off with a fine file and garnet paper, washed thread off with petrol, re-oiled, and now sliding perfectly.

Just as well this was needed because there was filth in the oil reservoir and in the gearbox …

And the grubscrew for the driveshaft bush had worked loose.

Edited By Nigel Brown 7 on 10/02/2018 22:44:18

Edited By Nigel Brown 7 on 10/02/2018 22:45:44