Straight lengths of vitreous pipe can be cut down (e.g. if you think you need between 40cm and 65cm you could by a one metre and cut to length)
Black vitreous pipe always fits into stove “tapered end downwards”. In other words the male is on top inserting into the female below ;)
The reason for this is that condensation runs down the pipe and we do not want it escaping at the joints. If black pipe is a loose fit into the stove collar use fire rope in the gap (if gap 5mm or more) or use fire cement in the gap (if gap 4mm or less). Vitreous pipe and stove collars rarely match well.
Adaptor needs a couple of self tapper screws through it and into the adaptor, to prevent the adaptor being pushed out of the black pipe when sweeping (not shown in picture below). One either side of pipe is plenty. Self tappers and very strong drill bit are supplied in “Useful Items Pack” which is also included with all Fitting Packs (ten off self tappers in pack).
Bolts secure liner into adaptor.
Fire cement should be applied to the gap at the top of the adaptor as well as any gap at the bottom of the adaptor.
Note that joints between sections of vitreous pipe DO NOT require fire cement. Fire cement is used where there is a gap at the stove collar and for sealing gaps at the adaptor. You do not need to get obsessed about making joints airtight. Gaps actually let air INTO the flue as the chimney sucks from the top (hence best to seal reasonably well). Smoke would only exit via gaps if something has gone wrong and then it would also leave via air vents in the stove anyway.