A winding mandrel (1) in a winding apparatus for producing a liner hose (2) for the lining of channels and pipelines, which comprises an inner film hose (4) and a layer arranged thereon made of at least one fibrous strip (6) wound in an overlapping manner, which is impregnated with a liquid reaction resin, with a base body (8), on which at least two guide mechanisms (10, 12) are accommodated, each comprising a continually circulating belt (14, 16), by means of which the inner film hose (4) is moved in a feed direction (A), is characterized in that the first guide mechanism (10) is coupled by fixed mounting to the base body (8), and in that the circulating belt (16) of the second guide mechanism (12) can be moved in a plane extending perpendicularly to the feed direction (A) and is forced away from the upper side of the base body (8) by means of pressing means (18; 118) with a preferably substantially constant force.