Tag Archives: torque

Hex Lag Screw

Gimlet Points on Lag Screws

Are gimlet points (threaded points) required on large diameter lag screws?

A lag screw, also referred to as a lag bolt, is a heavy wood screw with a spiral thread and a hex or square head used for driving it into wood. Large diameter lag screws typically do not require gimlet points because of the need for a pilot hole to lower the torque required to... Read more

Lag Screw Torque Specifications

Are torque specifications or values available for lag screws?

There are no documented torque values for lag bolts or screws. The reason for this lies in the definition of torque when discussing threaded fasteners. To put it simply, torque is a measure of the twisting force required to spin a nut up along the threads of a bolt. Lag screw threads are driven into wood, and therefore,... Read more

Torque Charts and Anchor Bolts

Do torque charts for tensioning fasteners apply to anchor bolts?

The AISC Steel Construction Manual, 13th Edition has this to say about anchor rod nut installation. “The majority of anchorage applications in buildings do not require special anchor rod nut installation procedures or pretension in the anchor rod. The anchor rod nuts should be “drawn down tight” as columns and bases are erected. This condition... Read more