On Monday, 13 May 2019 21:20:18 UTC+1, Tim+ wrote:
How do you do it?

Our log burning stove sits in its inglenook with its unjointed vertical
chimney pipe emerging from the flat top of the stove and straight up
through the top of the inglenook, presumably through a register plate or
some such thing.

The bottom end of the flue is concealed somewhere behind/above the fireback
and whilst there is a collar around the base of the pipe but this doesnt
seem to move to allow removal of the flue pipe.

Im guessing that the pipe must come out somehow to permit sweeping but
its not obvious to me.

Your chimney should be fitted with an insulated corrugated flexible liner.
The problem is tar, most of it will be at the top of the chimney. In the last foot where the gases hit the cold air.
It can't be brushed out,it has to be scraped.
If there is a large accumulation it can catch fire and can burn the house down if you're unlucky. Melt the liner if you're lucky.
It can be hand scraped from the top.

The best way is prevention, have a good blaze once a week to burn off the tars before too much accumulates.

It's all down to the crap inefficient stoves commonly sold in the UK.

If your chimney has no liner fitted, you are in the ****. There can be tar the whole length of the chimney, virtually impossible to remove and a fire hazard.