On Tue, 12 Jun 2018 23:32:31 -0700 (PDT), wrote:

Luckily the brass bit does come out it is secured using a clip the other side.

Whilst that is good, I'd still not bother trying to solder any of
those bits together because it will still probably melt the sheath off
the outer.

Clean the inside of the brass bit out with some coarse abrasive paper
/ round file / sharp small screwdriver (to remove and debris and
create a key) and clean both parts with a suitable solvent.

Mix up some suitable quantity of a quality epoxy, apply to both parts,
put together and leave 24 hours. Refit and just forever without that
part ever being a problem ever again?

Personally I think JB Weld would be ideal (if not overkill) but it's
not quite so easy to get in the UK as it was (but still on eBay etc).

Cheers, T i m