Abstract: A mounting bar for a road making machine having adjuster bars which are pushable out laterally to adjust the working width and which are arranged behind a main bar. Guide tubes for guiding the adjuster bars for telescopic extension are movably supported on the main bar by connection means for movement in the direction of extension of the adjuster bars. The conection means is arranged between the main bar and an end of each guide tube remote from the adjuster bar.

Abstract: A trench cutter for excavating trenches and for laying water pipes and drainage pipes into trenches consisting of a travelling cutter chain with a jib supporting the cutter chain, the jib being pivotable in a vertical plane. A pipe laying duct is included for entering the excavation and sliding on the bottom of the excavation trench, the laying duct being pivotably connected to the jib. A duct guide arm extends parallel to the back surface of the pipe laying duct for supporting the duct vertically so that it faces the cutter chain. A plurality of parallel guide rollers have one end pivotably connected to the duct guide arm and their opposite end connected to the outward drive shaft of the trench cutter. The drive shaft of the trench cutter is pivotably connected to the free end of the jib.