BS EN 975-1:2009 pdf download
BS EN 975-1:2009 pdf download.Sawn timber – Appearance grading of hard woods Part 1: Oak and beech.
4.3.2 Criteria linked to the structure of the hmber
— Knots (saze, nature, degree of antergrowth, frequency);
— Shakes and checks.
Slope of grain;
Barkpocket:
— Sapwood (for oak): unless specified in the contract, solxd sapwood is permitted without limit in all grades.
NOTE Unsound sapwood is considered according to grading criteria given In Tables of Clause 7. lnduded sapwood.
4.3.3 Sawing characteristics
Boxed heart:
— Exposed ph;
NOTE Presence of pdh on un-edged boards is not a qualitative elemenl for downgrading b..4 width reduction may be considered
— Wane
4.3.4 Warp Bow,
— Spiwig,
— Cup.
— Twist
4.3.5 Fungal and insect attacks
4.3.6 Stains
— Red heart (In beech):
— Black streaks,
Dote:
— Rot
— Brown oak;
— Other discolorations
6 Acceptance of batches
6.1 Un-edged boards
Unless otherwise specified by the purchase recephon with quality acceptance of individual selected un-edged boards and boules shall take place on the sellers premises to allow width or length reduction to be carried out if necessary (see 422).
6.2 Square edged timber
Reception can be carried out either on the seller’s or the buyer’s premises, as mutually agreed, using random
sampling method given In CEN!TS 12169,
7 Grading rules
7.1 Grading face
a) For individual selected un-edged boards
Take into account features which are on the falling lace, wtach is defined as the face which is vistle on the production line, after sawing.
In the case of specific measurement, the quality is determined by the face, the width of which is measured
b) For boules
Take mto account features which are on the upper face In the stackmg position to form the boule.
C) For strips and square edged timber
Take into account features which are on the best face.
7.2 Un-edged boards
7.2.1 Grading area
A notional area of 0,2m x 2,0 m containing the maximum nLrnber or the largest features on the grading face determines the grade of each board.
Feaftes located less than 10 cm from edges or ends of un-edged boards are not considered, unless the resumng width and length is insufficient to inscribe in an area of 0,20 m x 2 m. This manner of dorng is not valid for 0-BA and Q-SA classes; only width reduction can be used arid it is limited to 113 of the width,
7.2.2 Presence of a solitary feature (only one)
Un-edged boards cannot be downgraded by the presence of only one feature which is not accepted in a
grading. Consequently, this feature is accepted with a width or length reduction.
7.3 Strips and square edged timber
7.3.1 Knots
Take into account knots in the most penalized linear metre or the whole piece ifthe length is< 1 m.
Equivalence concept, except for Q-F1a. This llows any repartition of knots, providing:
-each knot diameter is under maximum alowed diameter,
-the sum of diameters is below the maximum permitted.
Example for QF-2:
the maximum allowed diameter of knot is 25 mm;
the maximum number is 3, so the sum is 75 mm (25 mmx 3).
One possile repartition is 4 knots of 10 mm, 1 knot of 15 mm and 1 knot of 20 mm.
7.3.2 Other features
These features are taken into account on the whole piece.
7.4 Baulks
Take into account features on the whole piece, except for dead knots where the maximum number is
determined by linear metre.