Graco 18C680 ProSurface Joint Knife 4 in

Graco 18C680 ProSurface Joint Knife, 4 in — What It Fits, Where It’s Used & How to Choose

The Graco 18C680 is a 4-inch joint knife from the ProSurface finishing system, purpose-built for precise drywall and plaster work. Its stiff chrome-steel blade and over-molded non-slip handle give you the control needed for tight areas, patching, screw heads, and finishing seams before final sanding and paint.

Where it’s used

• Interior drywall/plaster finishing: skim coating, feathering butt joints, taping touchups, corner detail, and patch repairs
• Residential remodels, new construction, and commercial interiors requiring a smooth, professional finish

What it fits

This hand tool is part of Graco’s ProSurface lineup and complements ProSurface smoothing blades and accessories. It’s also included alongside the 6-inch knife in the ProSurface Drywall Tool Kit, making it easy to standardize tools across your finishing workflow.

Key features

• Precision stiff chrome-steel blade for a smooth finish and crisp edges
• Aluminum/steel construction for durability on busy jobsites
• Over-molded non-slip grip for comfort and control during long sessions

How to confirm it’s the right part

1. Match the part number: 18C680 (4 in / ~100 mm joint knife).
2. Check your task scope: ideal for patching, seams, screw heads, and tight areas; pair with wider blades for large surfaces.
3. Verify ProSurface compatibility if you’re building a coordinated tool set.

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