Abstract: An adjustable-height stepladder has an upper-front frame and an upper-rear frame interconnected by a top member. The upper-front frame and the upper-rear frame each have an elongate slide track. A lower-front frame, wider than the upper-front frame and positioned centrally rearward thereof, has a pair of rails, each having a slide mechanism slidingly engageable with the slide track of the corresponding upper-front frame rail. A lower-rear frame, wider than the upper-rear frame and positioned centrally forward thereof, has a pair of rails, each having a slide mechanism slidingly engageable with the slide track of the corresponding upper-rear frame rail. Each slide mechanism has a hinged swing arm and a biasing spring, the combination of which allows the slide mechanisms to engage the slide tracks although the lateral distance between the upper-frame rails and their corresponding lower-frame rails may vary.

Abstract: A method of reducing slot width in slotted tubular liners. A slotted tubular liner (1) is provided having an interior surface (3), an exterior surface (2) and a plurality of slots (4) extending between the interior surface and the exterior surface. One or more contoured rigid forming tools (7) are provided. Pressure is applied to either the interior surface (3) or the exterior surface (2) of the slotted tubular liner (1) with the contoured rigid forming tools (7). The contoured rigid forming tools are then moved in a sweep pattern traversing either the interior surface or the exterior surface of the slotted tubular liner, until plastic deformation narrows the width of the plurality of slots (4) to within desired tolerances. The method does not require the same precise positioning of previously known methods and, as such, provides a combination of increased output and lower cost.