a slurry in the box and after several minutes settle back onto the screen in a uniform layer the box and screen are lifted out of the bath and the screen removed from the frame the layer of coated fibers is flipped upside down onto a drying screen and allowed to drain in order to be able to obtain a uniformly thick fiber mat the viscosity of the liquid mixture which coats the fibers should be low which is herein and in the claims intended to mean on the order of the viscosity of water if the bath is too viscous the fibers may not settle back onto the screen or if they do settle it may not be in a uniform manner or settling may take too long viscosity of the bath increases as the furfuryl alcohol polymerizes the mixture should retain its low viscosity for at least several hours so that a reasonable number of parts can be made before the mixture is unusable since the rate of polymerization is controlled by the amounts of catalyst and water in the mixture such amounts must be carefully controlled enough catalyst must be present to assure polymerization upon heating of the mat yet enough water must be present in relation to the amount of catalyst to prevent too rapid polymerization of the bath mixture at room temperature although in this embodiment the mixture of furfuryl alcohol phosphoric acid and water is prepared before the carbon fibers are added we do not believe that this is critical to the invention for example the carbon pitch fibers could first be dispersed in furfuryl alcohol a mixture of water and phosphoric acid can.