Cable Grommets / Cable Ports: Standard Dimensions (60mm, 80mm) & Routing

May 15, 2026

A cable grommet, also known as a cable port or desk tidy grommet, is a furniture fitting designed to neatly guide cables through desk tops or cabinet back panels. It protects cable insulation from sharp timber edges, prevents cables from slipping, and creates a tidy workspace. The most common drilling sizes in furniture making are 60 mm and 80 mm.

What Exactly Is a Cable Grommet?

A desk cable grommet typically consists of two main components: an outer mounting ring (sleeve) pressed into the routed or drilled opening in the desk top, and a removable cover.

The cover features an adjustable aperture, frequently fitted with a brush seal. This brush mechanically holds the routed cables in place. The grommet acts like a conduit for your hardware setups – gathering loose tangles below the desk into a neat bundle above, whilst preventing heavy multi-way extension leads or power supply units from dragging cables downward.

Shapes, Materials, and Finishes

Choosing the right fitting depends on the panel material and flush-fitting requirements.

Shapes: The standard in panel construction is the round cable grommet, as it is easiest to drill using rotary tools. For modern office systems, rectangular cable grommets or square cable grommets are increasingly favoured. These usually require CNC machining or manual cut-outs using a router.
Materials: A metal cable grommet, often made from zinc die-cast or aluminium, provides high mechanical strength and torsional rigidity. For standard furniture construction or lighter usage, a plastic cable grommet is frequently used.
Colours: To visually coordinate the fitting with the finish of chipboard or solid timber, a wide range of surface finishes is available. Popular options include black cable grommets, white cable grommets, as well as metallic finishes like silver cable grommets.

Dimensions and Standards in Furniture Construction

In European furniture making, two standard diameters have become established for round models, based on the drill hole size (cut-out diameter):

60 mm: The 60mm desk cable grommet is the standard size for conventional workstations. This diameter provides enough clearance for cables from one or two monitors, computer peripherals, and standard mains plugs when the cover is removed.
80 mm: The 80mm desk cable grommet is installed at workstations with higher cable volumes. Thick kettle leads (IEC power cables), complex docking station looms, or wide DVI/VGA connectors pass through this opening effortlessly.

Installation and Routing

Installation requires precise tools to prevent tearing out laminated surfaces.

Required Tools:

Drill or cordless screwdriver
Hole saw (core drill) or Forstner bit (Ø matched exactly to the nominal grommet size, e.g., 60 mm)
Sandpaper (120 grit)
Rule and set square

Step-by-Step Instructions:

Positioning: Mark the centre point of the hole on the desk top. A distance of 50 mm - 80 mm from the rear desk edge is recommended. Before drilling, always verify that the desk frame crossbar underneath is not obstructing the chosen spot.
Drilling: Drill strictly vertically using the hole saw. To prevent tear-out on the lower melamine coating, drill from the top until the pilot bit pierces through the underside. Then turn the panel over and finish the hole from the opposite side.
Edge preparation: Lightly smooth the sharp cut edge of the core material with sandpaper.
Press-fitting: Push the outer ring of the cable grommet flush using gentle pressure. In cases of slight tolerance variations from the hole saw, the ring can be secured into the timber with a small amount of mounting adhesive.