A case study of large tablet manufacturing in the chemical industry is presented. Since the tablets are much larger than the usual scale in the pharmaceutical industry, common practice that was developed mainly for pharmaceutical tablets could not be applied directly. Customer complaints concerning damaged tablets were the reason for this comprehensive study, which was aimed first at evaluating a testing method for process control, then to provide some hints for stabilizing the manufacturing process and for producing stronger tablets. Three test methods were evaluated: measuring compression and tension crush strengths and wear tests in a rotating drum. It was shown that the wear test provides sufficient results faster and easier than the ether methods. By testing hundreds of tablets, produced in various batches, production parameters such as granule aging, surrounding humidity, tableting pressure and tablet aging were evaluated in order to provide stronger tablets. The strongest tablets were achieved by using fresh granules at very high humidity and compacting pressure and by allowing the tablets to age for at least 2 weeks.