On Tuesday, June 11, 2019 at 11:13:38 AM UTC+1, DerbyBorn wrote:
of hot water with a dash of washing
powder. Vinegar, perhaps?


Are you sure it is getting a flow through the pipe. It sounds like you have
done what was needed. (Drill seems a bit over the top)

FWIW I have a small collection of 'wires' cut from old guitar strings when
trying to clear blockages like this. You then have a variety of diameters, and
the wound surface on the larger diameter strings is good to abrade the inside
surface.

J^n