A 1929 article by Fritz Keunecke of Barmen, Germany, explaining how fancy lace is made on machines and how the process relates to hand bobbin lace. It covers the machine gauges and speeds, the Jacquard-controlled bobbin plates and guide mechanisms, and one-thread versus multiple-thread machines. Much of the text deals with thread tension devices, comparing weighted bobbins with helical-spring bobbins, including spring 'lot' ratings and tension figures. Illustrated with diagrams of bobbin interlacing, machine sections, and bobbin mechanisms, plus photographs of a Jacquard lace machine and lace samples.

Second installment of Fritz Keunecke's serial on machine-made fancy laces, covering the mathematics of thread tension on braiding and lace machines. It derives equations for travel, speed and acceleration of the thread tension eyelet as the yarn carrier moves around its plate, using a 44-carrier, one-thread lace machine running at 240 rpm as a worked example. It then compares how acceleration affects thread tension in carriers using a tension weight versus a tension spring, with diagrams of the curves.

Third installment of Fritz Keunecke's series on machine-made fancy laces, covering the influence of friction on thread tension in lace-machine carriers. It derives rope-friction formulas and reports experiments with a spring scale and a rotating-pulley rig on cotton, luster cotton and rayon yarns with steel and glass eyelets. It then compares tension-weight carriers with tension-spring carriers and discusses the effect of periodic stopping and starting on the one-thread lace machine. The text is mathematical and experimental, with many graphs, tables and apparatus diagrams.

Concluding part of Fritz Keunecke's series on machine-made fancy laces, focused on thread tension in braiding-type lace machines. It covers how bobbin release affects tension and describes experiments measuring thread tension on a running experimental machine with a torsiograph recorder. Weight carriers are compared with spring-tension carriers at different turning speeds, with and without carrier stops. The summary finds that spring carriers keep tension steadier at higher speeds, while weight carriers show tension rising sharply with speed, and it points to bobbin release as the main cause of thread breakage.