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Black Log Timber Lag Screw

Structural • Corrosion-Resistant


Black Log Timber Lag Screw

Structural • Corrosion-Resistant

Heat-treated hardened steel
#14 x 2ʺ to #14 x 14ʺ and #17 x 4ʺ to #17 x 9ʺ
Hex Washer Head
5/16" Hex

Compatible with treated lumber, but areas within one mile of saltwater, near swimming pools, exposure to corrosive chemicals, or other areas where corrosion is more likely to occur, such as livestock confinement, use the proper size, grade and type of Big Timber Stainless Steel Fasteners. Big Timber Stainless Steel Fasteners should be considered if available. BL is not available in stainless.

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Big Timber Fasteners Product Demo BL

Common Uses Include

• Truss Hold-Down
• Log Construction
• Timber Frames
• Laminated Beams
• Ledger Boards
• Landscape Timbers
• Deck Posts
• Fencing

NOTE: Always follow lumber manufacturer’s recommendations.

Benefits and Features:

• Heat-treated hardened steel for high tensile strength and high shear strength
• ACQ compatible 1000 hour ruspert coating in an attractive matte black finish
useful with many brands of outdoor or indoor decorative hardware
• Wax coating enhances performance, reducing the torque for a smoother drive
• Possible replacement for 3/8″ lag screws and potentially larger
• Approved for use in ACQ pressure treated lumber
• Type 17 tip for faster precise starts which eliminates “walking”
– Provides for easy insertion without pre-drilling
• Aggressive thread for greater withdrawal strength
• Structural hex head screw backed by certified independent testing (TER 1907-02)
– International Building Code and International Residential Code compliant
• 6″BlackLog(BL) screws are a great alternative to labor intensive hurricane clips
– For rafter or truss to double-top plate applications, the 6″ BL can easily be installed at a 15-30° angle and is a code compliant

BL Product Options

0.189" | 5/16"2" to 14"1,085 lbf (Shear 725 lbf)
0.224" | 5/16"4" to 9"1,990 lbf (Shear 1,240 lbf)
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