Drawing of glass fibres is an important industrial process used for manufacture of a variety of materials. A variety of furnaces and machines exist for manufacture of glass fibres, but all share similar problems with control of the fibre diameter and breakage of the fibres during the extrusion process. In many cases, control systems are not configured to monitor the most critical process variable - temperature of molten glass in the furnace, but instead use only furnace crown temperature. This work seeks to develop an estimator-based LQR control model to monitor molten glass temperature and winder speed for good production quality. When a disturbance in ambient temperature and/or molten glass depth happens, the control system still performs as expected.