Tough one, Derek. I was fortunate after my trolley got smashed up at Carnac. Maybe the smashing up helped, but the stub came out easily. I can only suggest whatever combination of the following you can manage:
- heat the outer tube and cool the inner one
- outer tube in a decent vice, tightened sufficiently to stop rotation with pipe wrench on stub (as soon as you can after the above)
- put a tube onto the handle of the pipe wrench for extra leverage
- do this repeatedly in opposite directions
- keep adding WD 40 or similar when cool, leave overnight and try again
- just try for an imagined bit of movement in opposite directions each time
- persist
If the above doesn't work, buy a new tube and two new stubs
.
Expect you've done all that. Expect the wrench slipped, too, but file a couple of flats onto it if it did. Before giving up completely, enquire with a local engineer about the idea of cutting the end off and drilling out the remaining inner tube.
Good luck.