Screw withdrawal force is an indicator of the strength, density and shear modulus of wood. Therefore, Fakopp Enterprise has developed a portable screw withdrawal force meter. The applied screw diameter is 4mm, the length of the thread is 18 mm. The screw withdrawal force is a local parameter, but selecting a representative locations on a beam, it can provide useful information in wooden structure evalsuation.
- Drive the screw into the wood material, perpendicular to its surface.
- Connect the cable of the force transducer to the display unit R320.
- Switch on the unit by pressing the “ON” button for 3 seconds.
- Select the Peak hold function.
- Start the screw withdrawal process by placing the mechanics over the screw. Catch the screw head by the fork of the force transducer.
- Slowly turn the handle clockwise until the screw is removed. The speed of the withdrawal should be approximately 0.5 mm/s.
- Record the maximal force value and press the “Max” button before the next test to reset the display.
- Screw withdrawal mechanics with force transducer
- Display unit, R320
- Screws and screwdriver
- Rechargeable battery and charger
- Aluminium carrying box
- 10 special screws
- User manual