How are spade bits manufactured?

     
 

How are spade bits manufactured?

 
         
         
  Shop for Spade Bits  
         
         
  An example of a spade bit  

As spade bits are less complicated in design than most other bits, their manufacturing process is much simpler.

 
         
  Image showing the drop forging process by which spade bits are manufactured  

The end of the cylindrical steel blank is heated and drop forged into a flat spade shape. The process of drop forging involves a heavy piece of metal, such as a power hammer, stamping steel into a mould while it is hot, and so this method is particularly well suited to creating the spade bit’s flat head.

 
         
  A bench grinder which is used to grind the centre point and spurs onto a spade bit  

The lips, spurs and centre points are then sharpened on a grinding wheel.

 
         
  Diagram showing the position on a spade bit where you might find a hole, designed to pull cables back through wooden partitions after you have drilled through them.  

In some bits, a hole is drilled behind the central point to allow for a cable to be threaded through.

 

For more information, see: {{widget type=”cms/widget_page_link” title=”How to use a spade bit to pull a cable through a wall” template=”cms/widget/link/link_inline.phtml” page_id=”3299″}}

 
         
  Close up of a size stamp on a spade bit  

The width of the bit is then stamped on the remaining flat space so it can easily be differentiated from others.