Abstract: A method of predicting warp of lumber that might be sawn from any given log is disclosed. The method involves measurement of stress wave velocity in the tree stem, either as a standing tree or felled log. A scan is then made to define the exterior geometric configuration of the log. In particular, measurements relating to lack of longitudinal axis linearity (sweep) or irregularity of cross sections of the log are important. Stress wave values and selected geometric parameters are entered into a multivariate regression equation to predict warp propensity of lumber that might be sawn from the log. Separate equations are required for each species for prediction of crook and bow. The equations are originally derived by examination of a representative population of logs of the particular species and locale and measurement of warp in lumber sawn from the logs. The stress wave information may be combined with the geometric characteristics in the computer associated with a log scanner at the green end of a sawmill.

Abstract: The invention is based on the discovery that the wood of certain trees having genetically modified lignins has plastic properties far greater than that of trees of the general population of the same species. In particular, trees have been found to have significantly increased plasticity in which the lignin is of a less crosslinked or more linear type, of lower molecular weight, of a relatively higher content of lignin precursor monomers or oligomers, or is more readily extractable by the usual methods. Wood from these trees can be readily molded by pressure and heat into two or three dimensional articles. The ability to be molded can be significantly enhanced by the addition of plasticizers.

Abstract: A system for estimating a velocity of a stress wave induced in a log or tree stem is used to maximize the value of wood products produced. An accelerometer is placed against the log while the log is struck with a pneumatic hammer. By monitoring the signals received at the accelerometer, the velocity of stress wave can be determined. Based on the velocity, an estimate of the modulus of elasticity (MOE) for the wood in the log is made. A price table is selected that relates different sizes of lumber having the determined modulus of elasticity to a current market value. The log is then cut such that the value of the lumber produced is maximized.

Abstract: A rapid curing adhesive for wood finger jointing and laminating and a method of its use are disclosed. The adhesive consists of two parts that are used as a honeymoon system. One part is used on one side of the joint being formed and the other part on the other side. When the parts are joined under pressure a very rapid reaction occurs resulting in a durable weather resistant joint. Wood finger joints bonded with the adhesive can be handled for further processing within as little time as 15 seconds. The first part of the adhesive is a conventional resorcinol-formaldehyde or phenol-resorcinol formaldehyde resin containing a hardener such as an alkylene group donor. The second part is a similar resin lacking any hardener but containing a modifier which is a heterocyclic oxygen and nitrogen containing compound. Morpholine has proved to serve well as the modifier. The hardener in the first part is used in a sufficient amount to effect a thermosetting cure for the resin used in both parts.

Abstract: The invention is a method of assisting lumber grading using an electro-optical scanning system. A first critical determination is determination of pith position of the log from which the lumber was cut, relative to the scanned faces. This then indicates knot orientation. With knot orientation known, knot size and position data also determined by the scanning system can be used to accurately estimate cross sectional area of the knots. From this point a tentative lumber grade can readily be assigned. Pith position is indicated by a number of factors including wane, knot counts on each of the faces and the presence or absences of spiky faces. A preferred form the scanner is one which measures localized wood fiber angles relative to three orthogonal axes. These fiber angle measurements reveal grain slope disturbances on the lumber which are indicative of many types of defects including knots. The system has been used for grading lumber at speeds as high as 350 m/min. with considerable accuracy.

Abstract: The invention is a method of assisting lumber grading using an electro-optical scanning system. A first critical determination is determination of pith position of the log from which the lumber was cut, relative to the scanned faces. This then indicates knot orientation. With knot orientation known, knot size and position data also determined by the scanning system can be used to accurately estimate cross sectional area of the knots. From this point a tentative lumber grade can readily be assigned. Pith position is indicated by a number of factors including wane, knot counts on each of the faces and the presence or absences of spiky faces. A preferred form of scanner is one which measures localized wood fiber angles relative to three orthogonal axes. These fiber angle measurements reveal grain slope disturbances on the lumber which are indicative of many types of defects including knots. The system has been used for grading lumber at speeds as high as 350 m/min. with considerable accuracy.

Abstract: The present invention is a method of determining edge profile of one or both edges of an elongated member such as a piece of lumber or structural timber. This can be done at high speed as the member is conveyed past a scanning station where it is subject on the conveyor to translational and/or rotational movement relative to a baseline. The baseline is located generally parallel to the longitudinal axis or centerline of the member. At the leading end of the member the instantaneous edge height above the baseline is measured at three spaced apart locations. These measurements are continued along the member with each sampled portion substantially overlapping the previously sampled portion. For each individual sampled portion any deviation from linearity of the edge at the interior measurement position is determined from a chord drawn between the end measurement positions. Knowing these deviations the edge profile can be readily computed for the member.