ID HQ SERIES ARMATURE [DW28490] [9"] ANGLE GRINDER SPARE PART - 29001

Yes. This ID HQ Series Armature is specifically engineered as a DeWalt-type replacement for the DW28490 9-inch angle grinder. It is dimensionally matched to the original — including shaft diameter, core stack length, and commutator segment count — ensuring a direct drop-in fit without any modification to the tool housing or brush gear.

The ID HQ Series is manufactured to OEM-equivalent specifications, using high-grade copper windings, a precision-machined commutator, and a laminated silicon-steel magnetic core. It carries CE Machine Test certification, confirming it meets the same safety and performance standards as the original. For repair workshops and professional technicians, it offers a cost-effective alternative without compromising on reliability or output.

Each order contains one ID HQ Series Armature unit (1 piece), supplied ready for installation. The armature is CE-certified under machine test standards and is packaged to prevent transit damage to the commutator and winding surfaces.

The armature is the rotating core of the angle grinder's electric motor. It consists of a laminated magnetic core, copper windings, and a commutator. When electrical current passes through the windings, it interacts with the stator's magnetic field to generate rotational force — converting electrical energy into mechanical energy that drives the grinder's disc. A worn or damaged armature results in loss of power, excessive sparking, or complete motor failure.

Installation requires standard power tool disassembly tools — typically a set of screwdrivers, a bearing puller, and a soft-faced mallet. The DW28490 armature replacement is a direct-fit part, so no machining, grinding, or adaptation is needed. It is recommended that installation be carried out by a qualified power tool repair technician to ensure correct brush seating and bearing alignment.

Yes — it is strongly recommended to fit new carbon brushes whenever an armature is replaced. Used brushes have worn to the profile of the old commutator and will not seat correctly on a new, freshly machined commutator surface. Installing new brushes alongside the new armature ensures optimal electrical contact, reduces run-in time, and prevents premature wear on the precision-machined commutator.

Excessive sparking and power loss are classic symptoms of a worn or damaged armature. Common causes include burnt or shorted windings, a worn commutator with deep grooves between segments, or an open circuit in the coil. Inspect the commutator surface for discolouration, pitting, or uneven wear. If the commutator cannot be re-skimmed to within tolerance, replacing the entire armature assembly with this ID HQ Series unit is the most reliable repair solution.

Excessive vibration after an armature replacement is typically caused by an incorrectly seated bearing, an unbalanced armature, or a misaligned rotor shaft. Ensure both the drive-end and commutator-end bearings are fully pressed into their housings and that the armature shaft runs true. If vibration persists, check that the correct armature for the DW28490 has been fitted — an incorrect stack length or shaft diameter will cause imbalance and premature bearing failure.

If the tool fails to start after an armature installation, first verify that the carbon brushes are making firm contact with the commutator and that the brush springs are correctly tensioned. Check all internal wiring connections for continuity and confirm the field coil is intact. Use a multimeter to test for continuity across the armature windings — a reading of zero or infinite resistance indicates a winding fault. If the armature tests correctly, the issue may lie with the switch, field winding, or power supply rather than the replacement part.