Specification

Hardwood Plywood Grading Guide 2015 columbiaforestproducts.com 23
ASH, BIRCH, MAPLE AND POPLAR: ROTARY-CUT, QUARTER CUT, PLAIN SLICED (From Table 3.1 ©)
Natural Characteristics A Grade B Grade C Grade
Small Conspicuous Burls & Pin Knots — Comb. Avg. Number 10 per 4 x 8' panel 16 per 4 x 8' panel No limit
Conspicuous Burls — Max. Size 3/8" 1/2" No limit
Conspicuous Pin Knots
Average Number
Max. Size: Dark Part
Max. Size: Total
1 per 8 sq ft
4 per 4 x 8' panel
1/8"
1/4"
1 per 4 sq ft
8 per 4 x 8' panel
1/8"
1/4"
No limit
Scattered Sound and Repaired Knots
Comb. Average Number
Max. Size — Sound
Max. Size — Repaired
Avg. Number — Repaired
No
1 per 8 sq ft
4 per 4 x 8' panel
3/8"
1/8"
1 per 8 sq ft
1 per 4 sq ft
8 per 4 x 8' panel
1/2"
1/2"
1 per 8 sq ft
Mineral Streaks Slight Slight Yes
Bark Pockets No Few to 1/8" x 1" Few to 1/4" x 2"
Worm Tracks Slight Slight; Ash Yes Yes
Vine Marks Slight Slight Yes
Cross Bars Slight Yes Yes
MAHOGANY, ANIGRE AND SAPELE: ROTARY-CUT, QUARTER CUT, PLAIN SLICED (From Table 3.2 ©)
Natural Characteristics AA Grade A Grade B Grade
Small Conspicuous Burls & Pin Knots — Comb. Avg. Number 6 per 4 x 8' panel 10 per 4 x 8' panel 16 per 4 x 8' panel
Conspicuous Burls — Max. Size 1/4" 3/8" 1/2"
Conspicuous Pin Knots
Average Number
Max. Size: Dark Part
Max. Size: Total
No
1 per 8 sq ft
4 per 4 x 8' panel
1/8"
1/4"
1 per 4 sq ft
8 per 4 x 8' panel
1/8"
1/4"
Scattered Sound and Repaired Knots
Comb. Average Number
Max. Size — Sound
Max. Size — Repaired
Avg. Number — Repaired
No No
1 per 8 sq ft
4 per 4 x 8' panel
3/8"
1/8"
1 per 8 sq ft
Mineral Streaks No Slight Occasional
Bark Pockets No No Few to 1/8" x 1"
Worm Tracks No No Slight
Vine Marks Slight Slight Yes
Cross Bars Occasional Occasional Yes
RED AND WHTE OAK: ROTARY-CUT, QUARTER CUT, PLAIN SLICED (From Table 3.3 ©)
Natural Characteristics A Grade B Grade C Grade
Small Conspicuous Burls & Pin Knots — Comb. Avg. Number 12 per 4 x 8' panel 24 per 4 x 8' panel No limit
Conspicuous Burls — Max. Size 3/8" 1/2" No limit
Conspicuous Pin Knots
Average Number
Max. Size: Dark Part
Max Size: Total
1 per 3 sq ft
10 per 4 x 8' panel
1/8"
1/4"
1 per 2 sq ft
16 per 4 x 8' panel
1/8"
1/4"
No limit
Scattered Sound and Repaired Knots
Comb. Average Number
Max. Size — Sound
Max. Size — Repaired
Avg. Number — Repaired
No
1 per 8 sq ft
4 per 4 x 8' panel
3/8"
1/8"
1 per 8 sq ft
1 per 4 sq ft
8 per 4 x 8' panel
1/2"
1/2"
1 per 8 sq ft
Mineral Streaks Slight, Blending Few to 12" Yes
Bark Pockets No Few to 1/8” x 1” Few to 1/4" x 2"
Worm Tracks No Slight Few
Vine Marks Slight Yes Yes
Cross Bars Slight Yes Yes