Bulk density (R) was calculated from oven dried weight and green volume according to the equation R = W / (W₁ - W₂). W is the weight of oven dried specimen, W₁ is the weight of saturated specimen, and W₂ is the weight of saturated specimen in water. The value (W₁ - W₂) was the weight of water which was replaced by the specimen.

Wood shrinkage

Size of specimen was 30 (radial) x 30 (tangential) x 5 (longitudinal) mm for radial and tangential shrinkage. For longitudinal shrinkage, the size was 30 (radial) x 5 (tangential) x 60 (longitudinal) mm. Shrinkage along radial, tangential and longitudinal direction (a_r, a_t and a_l) was calculated by the equation a = (l_g - l₀) / l_g x 100 (%), where l_g and l₀ were the green and dried dimension respectively. The volume shrinkage (a_v) was calculated by the equation a_v = { 1- (1 - a_t / 100) (1 - a_r / 100) (1 - a_l / 100)} x 100 (%). The moisture content of air dried specimen was 15 %.

Water absorption

The amount of water (mg) which was absorpted through the specimen surface area (cm²) exposed to water in the duration of 24 hrs.

Modulus of elasticity in bending

Based on JIS Z 2113.

Bending strength

Based of JIS Z 2113

Sawing rate

Sawing rate (m²/min) = Sawn area (m²) / Sawing time (min). Sawing rate was calculated from the sawn area and the sawing time when lumber was sawn at the maximum feed speed, under which the bent kerf did not occur, with a 1050 mm band saw machine with a carriage at a band saw speed of 41.2 m / min. A band saw used was 0.9 mm in thickness, 100-127 mm in width, 32 mm in pitch, 25 degrees in rake angle, 20 degrees in clearance angle, and 0.5 mm in amount of set and its every second teeth were tipped with stellite.

Drying time

Drying time

Cutting force (Cutting by rotating knife)

Estimated force during longitudinal cutting of kiln-dried, 12 % lumber (moisture content 12 %) with SKH₃ knives . Rotation speed of the knives were 900 rpm,

Knife life (Cutting by rotating knife)

Cutting length of kiln-dried lumber at 70 % of blemished lumber percent in longitudinal cutting with a SKH₃ knife. The knife rotated in 6120 rpm, and had 56 ^. cutting angle and 40 ^. knife angle. The depth of cutting was 2.0 mm and feed speed per knife cut were 3.0 mm.

Mass loss

Mean value of the mass loss (%) of specimens (20 x 20 x 20 mm) after 2 months by pure culturing in the bottle, based on the mass after dried for 48 hrs at 60 ^.C, according to the fungal durability test included in JIS Z 2101-1994 "Methods of test for wood". The fungi tested were Tyromyces palustris for brown rot, and Coriolus versicolor and Pycnoporus coccineus for white rot.

Shear strength

Block shear strength was determined according to ASTM D 905. Size of laminae: 2.0 cm (thickness) x 11.0 cm (width) x 37 cm (length). Grain direction: parallel - diagonal. Moisture content: 10-12 %. Spread rate: 330 g/m². Press condition 7-15 Kgf/cm² 0.7-1.5 MPa (pressure), 16-24 hrs (press time), 25-45 ^.C (temperature). Size of laminae was 2.0 cm in thickness, 11.0 cm in width, and 37 cm in length. The moisture content of the laminae was seasoned at 10-12 % before gluing. The lamination was carried out with 330 g / 1 m² adhesive under the pressure (0.7-1.5 MPa) and temperature (25-45 ^.C) for 16-24 hrs. Block shear strength was determined according to ASTM D 905.

Wood failure

Five-ply glulam were made under the same condition as the test for shear strength. Size of specimen was 10 cm in width 7.5 cm in length. Delamination tests were conducted for Urea resin adhesive based on JAS of laminated lumber and for Resorcinol resin adhesive based on ASTM D 1101.

Peeling lathe check

Percentage of lathe check depth to veneer thickness. The heartwood of green bolt was peeled under the condition of knife angle 21 ^., clearance angle 1 ^., depth of cut 1.02 mm, and 90 % of horizontal pressure bar opening.

Drying time

Drying shrinkage

Shear strength

Wood failure

Curing time

Curing time of unsaturated polyester resin vanish painted on flat or quarter-sawn lumber at temperature 20 ^.C and relative humidity 65-70 %. Ratio of a mixture of cobalt naphthenate (Co 5%) and methyl ethyl keton peroxide to the unsaturated polyester resin is 1:100 (in weight). No sizing and no undercoating. Film thickness is 250 micro m.

Adhesion strength

Adhesion strength of nitrocellulose clear lacquer painted three times on quarter-sawn lumber (moisture content 15 %). No sizing and no undercoating. Average coated paint weight is 400 g/m². Tested according to tensile testing of fancy plywood in JAS (Japan Agricultural Standards).

Chemical characteristics and extractives

Samples were ground in the Wiley mill so as to pass a 40 mesh sieve. All analysis were made according to JIS methods. The holocellulose was determined according to Wise. Alpha-cellulose was determined with isolated holocellulose according to the ordinary method using 17.5 % aqueous soduim hydroxide.

Pulping procedure

Sulphate pulps were prepared in 4 l stainless steel autoclave heated to a temperature of 170 ^.C by a controlled-temperature electric heater. The pulps, after washing, were screened on an 8-cut (8/1000 in. slot openings) screen plate. The pulps were bleached by a five-stage. The Lampen mill charged with pulp (equivalent to 24 g O. D.) at 3 % consistency was used for beating the pulps. Sheet making and testing were cariied out according to the appropriate JIS methods.