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Structural Timber Connections: Carriage Bolts vs Heavy Lag Screws
Engineering structural joints in heavy timber, deck posts, and roof trusses. Pull-through resistance, square under-neck locking, and washers.
Through-Bolting vs Blind Fastening
A Carriage Bolt (Coach Bolt) passes entirely through both timber members and clamps them with a nut and washer. The square collar beneath the domed head embeds into the wood to prevent spinning during tightening. Lag Screws are heavy-duty wood screws used when only one side of the connection is accessible.