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Pre-wind Plain Mandrel Tool (Body 1)

A slotted mandrel within a slim tool body that has a pre-wind nozzle

The pre-wind nozzle is necessary for the installation of screw locking wire thread inserts, where the insert must be compressed (pre-wound) prior to installation in the tapped hole.

Method of use

  1. Withdraw the mandrel from the main tool body
    • with a window style tool the mandrel will only need to be withdrawn to the window
    • with a full body tool the mandrel will be withdrawn completely
  2. Place the insert into the main tool body - either through the window or from the top end of the body as required - with the driving tang facing towards the nozzle
  3. Return the mandrel into the tool body, engaging the driving tang in the slot of the mandrel
  4. Move the mandrel with the engaged insert towards the nozzle
  5. Wind the insert clockwise into the nozzle until it meets the nozzle end 
  6. Place the tool squarely over the tapped hole
  7. Continue winding until the insert is positioned approximately 1/4-1/2 turn below the surface of the tapped hole
  8. Withdraw the tool.


Note: Excessive axial pressure can cause inserts to jump thread when transferring from the nozzle to the tapped hole - fine pitch threads are particularly prone to this.