Twenty minutes staring at a tape tangle is rough, but a snapped reel can usually be spliced back together at the break.

Were the terra cotta flues already glazed or pretty rough inside? That makes a big difference on how much you can lean on the poly brush without worrying. On rough clay I still run a wire brush first pass at low speed, then finish with the poly to get the fine dust the wire leaves behind. Just watch your rod speed in those old liners, the poly bristles can fold over and stop scrubbing if you spin them too fast.

Chasing rare nights builds character, mediocre skies build bad habits.