Our other sites:

What slotting & grooving router cutter

parts are available?

  buy router cutters  

Many slotting and grooving cutters have replaceable parts, they usually consist of eight basic parts:

  Parts diagram for a slotting and grooving router cutter     


  Example of an arbor compatible with slotting and grooving router cutters  

Slotting and grooving cutter parts are mounted on a steel bar, known as an arbor. As with a regular router cutter, an arbor has a shank at one end which is designed to fit into the router. However, instead of having flutes ground into the body of the tool, arbors have a threaded section below their shank, known as the spindle, on which the parts such as groovers and ball bearings are placed.

  Diagram showing the parts of an arbor for a slotting and grooving router cutter  

Abors are available with ¼" (6.35mm), 8mm (5/16"), 3/8” (9.5mm) or ½" (12.7mm) shank diameters, and are usually supplied with a set of shims and spacers. Arbors can be found in spare parts or there is a selection of arbors found in the Professional TCT range.


Groovers and profile blocks

  A groover with a cutting edge and gullet labelled  


Groovers consist of a steel disc tipped with two or more tungsten carbide cutting edges (or teeth).


Each tooth is ground to an exact width and has precise cutting and clearance angles to ensure that waste material clears quickly and freely. 

  Image showing that slotting and grooving router cutters can be stacked  

Groovers can be used singularly to cut very precise slots or grooves, or stacked to produce customised cutting widths and profiles. 

  Straight, radius and angled slotting and grooving router cutters  

They are available are in straight, radius, and angled versions, depending on the shape of groove you want to produce. You'll find a range of slotters and groovers available as spare parts as well as from the Professional TCT range.

  Slotting and grooving router cutter that comes in two halves and can be assembled with shims or spacers  

Some groovers also come in two halves, which can either be fitted together, or divided by spacers or shims, so that the width of cut can be varied. 

buy router cutters
  Examples of different types of profile blocks  

Profile blocks

Profile blocks are similar to groovers, but are much thicker, and rather than producing grooves, rout larger shaped profiles in material edges. They are usually designed for specific cutters.


Bearing guides

  Bearing guides of different sizes for use with slotting and grooving router cutters  

Bearing guides are used to set the depth of cut and to guide the cutter against the edge of the workpiece. Changing a bearing for one of a different diameter will change the depth of cut: the smaller the bearing diameter, the deeper the cut, and vice versa. Bearings are typically supplied individually or in packs. You'll also find bearing fixing packs, multi-bearing packs, plastic sleeve bearings, rubber shielded bearings, and Trade range bearings.



  A selection of spacers which are used to spread out parts of a slotting and grooving router cutter on an arbor to increase the size of a cut  

Spacers are small discs of metal that put space between the parts mounted on the arbor, allowing you to alter the cut that is produced.


Compared with shims, spacers are thicker, and used to create a larger distance between parts, hence their name. 



  A selection of shims which are used for finely adjusting the distance between slotting and grooving router cutter parts  

Shims tend to be much thinner than spacers and so are used for making finer adjustments to the position of the parts. They are useful for joint-making, where the cuts must be accurate in order for parts to fit together tightly.


Slotting and grooving cutters, as well as just the arbors themselves, are usually supplied with a set of shims.



  Metal washers can be found above the nut on a slotting and grooving router cutter  

Single or multiple washers are also used with slotting and grooving cutters. They are made of plastic or metal and are usually placed in-between a groover or profile block and a guide bearing, however, they can also be found above the nut. 

  Diagram showing the location of the washer on a slotting and grooving router cutter  

When all the parts are in place and tightened, the washer will help to distribute the pressure over the parts evenly, so that they’re not sitting at a crooked angle to one another. This is especially important for the groovers and profile blocks.


Washers also protect the surface of groovers and profile blocks from being marked by bearing guides, and help to keep dust and waste chippings ejected by the cutter away from the guide, ensuring it turns smoothly.



  A slotting and grooving router cutter that has been assembled and is ready for the nut to be tightened onto the arbor to secure everything into place  

For most slotting and grooving cutters, all parts are secured on the threaded section by a nut and washer.


The exceptions are arbors with an M12 thread, as these are designed to be used in conjunction with special groovers that have matching internal threads, allowing them to act as their own nut on the arbor spindle. 
shop for slotters


Wonkee Donkee reminds readers that bearings, washers and nuts are also found on regular router cutters



Tips for assembling slotting & grooving router cutters

  buy router cutters  
  A DIYer putting the nut onto a fully assembled slotting and grooving cutter  

The exact parts and order in which you assemble them on the arbor will vary depending on which cutter you are using and what type of cut you want to produce, so individual product instructions should be followed. 


However, there are some general tips that should apply when installing all slotting and grooving cutters:



  Check the arbor for burrs or scratches  
  • Always assemble cutters with care, first checking that the arbor is free of burrs and scratches


Groovers and profile blocks

  Diagram showing the recommended location for a groover  
  •  To reduce the risk of flexing, always fit groovers as close to the shank end of the arbor as possible

  Diagram showing how to set up and check multiple groovers on a slotting and grooving router cutter  
  • Make sure that each groover is facing the correct way - against the rotation of the router

  • When using more than one groover, always offset each of them (i.e. two groovers on the arbor would be set at 90 degrees to each other, three at 60 degrees and so on) to reduce the impact force of the cut.


Bearing guides

  Preventing damage to slotting and grooving router cutter components using shims  
  • When fitting bearing guides, always use spacers or shims to prevent the tips of smaller diameter groovers from touching either the bearing case or adjacent groovers. This will help to prevent damage and will allow bearings to turn freely


Lock nuts

  Attaching a nut to the tip of a slotting and grooving router cutter  
  • Before tightening, check that the lock nut threads are clean and undamaged


  • Take care not to cross thread the lock nut before tightening it firmly. This will help to prevent the arbor turning in the cutter bore

      buy router cutters   
Contact Us