Continuous Lamination of Lumber

Discusses the development of a technique which combines a double preheating process with a sliding belt continuous press developed by Washington Iron Works, for the continuous lamination of lumber. The machine produces laminated tongue and groove roof decking at the rate of 40 lineal feet per minute. A 60 foot preheat length and 40 foot press length were designed to meet the process requirements of 1-1/2 minutes of preheat time and 1 minute of press time. Assembly times of 2 and 3 seconds are used. A commercial formulation of phenol formaldehyde resin is used with some resorcinol resin added to hasten cure. Excellent results were obtained with a proportion of three parts phenol resin to one part resorcinol. The mixed cost is approximately 20 cents. Higher heat settings and pressures were needed for Douglas-fir than either West Coast hemlock or Western redcedar. All three were glued with ease. Boards with a moisture content range of 18 to 25 percent were glued successfully. Three 1-inch boards were laminated together in the pilot study described, but as many as 14 laminations of 2-inch lumber is quite feasible.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member