Black+Decker BDEG400: problems, parts and running costs

Checked: 2026-10-17

Summary

A budget corded 4-1/2 in angle grinder (6 A motor, 10,000 RPM, 4.5 lb, metal gear case) for homeowner grinding, cutting and rust removal. The recurring complaints are switch failures shortly after purchase, intense vibration and a cumbersome guard adjustment. Running costs are just wheels, brushes and electricity; it is a strong buy at $45.99 and a weak one above about $60.

Common problems and fixes

Switch failures — multiple owners report the on/off switch failing shortly after purchase; no failure rate has been published, so treat it as a known annoyance rather than a defect. The manual’s troubleshooting section routes cord/switch failure to a service center, and the 2-year limited warranty covers defects in material and workmanship. [5][2][11]
Intense vibration — some owners report it during extended use, making longer jobs less comfortable. [5]
Cumbersome guard adjustment — the guard swivels only about 270 degrees, not a full circle, and owners call its adjustment cumbersome. [5]
Missing parts — some units shipped without the spanner wrench or the side handle. [5][7]
No lock-on switch — the tool runs only while the paddle is held, which gets tedious on long cuts. [3][10]
No variable speed and no overload protection — fixed 10,000 RPM only, and it will not shut off automatically if bogged down. [3]
Wheels that will not loosen / drive slip — reported by some users. [7]
Gearbox grease — a separate r/Tools thread about a grinder making a rattling sound suggests factory gearbox grease may be too thin; not confirmed as a BDEG400 problem. [14]

Parts and consumables

Metal grinding wheel — included in the box; no cutting wheel ships from the factory, so cutting work needs a separate wheel. [1][4]
Cutting and grinding wheels — the main consumable; no wheel prices were confirmed in the research.
Replacement brushes — listed as a possible recurring cost; no prices confirmed.
G720 replacement parts — the same tool is designated G720 (G720-B3 Type 1) for parts ordering; replacement parts are sold through Black+Decker’s ToolServiceNet service network, though exact US stock and pricing were not confirmed. [2][12]

Yearly running cost

Not enough data for a yearly figure. No battery or charger is needed. The recurring costs are grinding/cutting wheels, replacement brushes if applicable, and electricity; no prices were confirmed in the research.

When it is a good buy

$45.99 at Black+Decker direct (2026-10) and $45.99 at Walmart (2026-10): strong budget value with the metal gear case, 3-position handle, spindle lock and 2-year warranty. [1][7]
$48.99 at Acme Tools (2026-10, out of stock, backorder only): still fair value. [3]
$59.37 at ToolUp (2026-10) or $63.04 at RSHughes (2026-10): weak value — alternatives from Makita (GA4530), DeWalt (DWE4011) and Ryobi become preferable. [8][9]
Above $75: poor value; the tool is outclassed by professional-grade alternatives at that price.
The tool is no longer sold at Lowes or Northern Tool, which may affect long-term parts and warranty support. [4][6]
If you need a lock-on switch, variable speed or overload protection, look elsewhere. [3]