Outside Corner Finishing Tool Simplifies Drywall Application

Ames Tools Corporation has patented an outside corner finishing tool that significantly improves how professionals apply drywall joint compound at external corners. The tool features an innovative design using dual plates with ball joint couplings that maintain proper spacing and angle control for superior finishing results.

The Problem

Applying drywall joint compound to outside corners presents distinct challenges compared to inside corner finishing. Traditional outside corner finisher tools have limitations in controlling material distribution across the corner profile, resulting in uneven application, inconsistent finished surfaces, and the need for additional finishing passes. Currently available finisher boxes apply materials through pivoting movement of a push plate, but these designs do not adequately address the specific geometry and control requirements needed for high-quality outside corner work.

Professional drywall finishers require specialized tools to achieve consistent, smooth corners with minimal rework, yet existing solutions force compromises between speed, consistency, and surface quality.

What This Invention Does

The outside corner finishing tool utilizes a novel splitter mechanism that divides drywall finishing compound into precisely controlled outlet streams. A first plate and second plate are coupled to the splitter through ball joints, allowing controlled movement and articulation. The ball joint design permits the plates to adjust their positions relative to the splitter while maintaining the structural integrity needed for consistent material flow control.

The key innovation is that the outlet of the first plate is spaced apart from the outlet of the second plate, enabling the tool to manage material distribution across both sides of an external corner simultaneously. This dual-outlet design provides better control over joint compound dispensing, allowing professionals to achieve superior corner finishing with single passes and reducing the need for additional finishing work.

Key Features

• Splitter Mechanism. A central splitter component divides incoming compound and directs it through separate outlets, managing flow to each side of the external corner independently.
• Dual-Plate Design. First and second plates coupled to the splitter provide dual outlet control, with spaced outlets optimized for outside corner geometry.
• Ball Joint Couplings. Articulating ball joints connect both plates to the splitter, allowing controlled movement and flexible positioning while maintaining structural support.
• Optimized Outlet Spacing. The spacing between outlets is engineered specifically for outside corner applications, ensuring proper compound distribution across the corner profile.
• Improved Material Dispensing. The tool design reduces compound waste, improves application consistency, and decreases finishing time compared to conventional outside corner techniques.

Who Is Behind It?

Ames Tools Corporation, through inventors Matthew W. Jungklaus and Michael T. Ventura, developed this finishing tool innovation. The patent was filed on 21 August 2025, claiming priority to U.S. Provisional Application 63/688,002 filed on 28 August 2024. Griffith Hack represents the application in Australia with offices in Melbourne, Victoria.

Why It Matters

This patent improves a fundamental construction technique used on nearly every drywall installation worldwide. By enabling faster, more consistent outside corner finishing, this tool can increase professional productivity while improving finished product quality. The innovation reduces labor time on finishing phases, translating to cost savings for contractors and improved economics for drywall finishing operations.

The development of specialized tools that address specific application challenges reflects the construction industry’s ongoing evolution toward more efficient, higher-quality methods and the value placed on innovations that streamline skilled trades.

Related Concepts

Drywall (also called plasterboard or gypsum board) is the dominant interior wall and ceiling material in residential and commercial construction across North America and Australia. After panels are fixed to framing, joints and corners must be finished with joint compound applied in multiple coats to create a smooth, seamless surface ready for painting. Outside (external) corners require particular care because the compound must be applied evenly to both faces of the corner simultaneously.

Ball joints are mechanical couplings that allow rotation in multiple directions while maintaining a fixed pivot point. In finishing tool design, ball joints provide the articulation needed for plates to self-adjust to slightly non-square corner angles encountered in real construction, ensuring consistent compound delivery without requiring the operator to manually compensate for imperfect geometry. Specialised finishing tools that automate compound distribution have been progressively displacing manual trowel techniques in professional drywall work.

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AU 2025220772 was published in the Australian Official Journal of Patents on 19 March 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.