Woodpeckers 641M-24 641 Square, 150mm is a precision layout and setup square built for woodworking. This is a woodworking square designed for accurate layout, machine setup, and assembly work. Model Number: 641M-24. If you want a compact square that is easier to keep close at hand than a full-size framing square, but still built to a much tighter standard than typical shop squares, this is the one.

This 150mm model is the metric version of Woodpeckers' 641 pattern, which makes it a smart fit for woodworkers who work in metric dimensions or just prefer finer metric layout. Woodpeckers laser engraves the scales on both sides of the blade, and the stated accuracy is ±.004 inch total accumulated error over the entire length of the scale. In real shop terms, that means cleaner reference lines, more reliable machine setup, and fewer small layout errors stacking up later in the project.

The big difference here is how the square is built. Instead of a light stamped body, the Woodpeckers 641M-24 uses a one-piece central core machined from cast and ground plate aluminum, with precision-pinned cheeks. Cast and ground plate aluminum is chosen for stability, which matters because a square only earns its keep if it stays square. The result is a tool with enough heft and balance to feel planted in use without being bulky.

Those pinned cheeks are set back to create a shoulder, and that shoulder is one of the most useful details on the whole tool. It lets the square register against the edge of a board without needing you to pinch and hold it in place the whole time. For marking stock, checking edge-to-face relationships, or setting up machinery, that hands-free registration speeds up the work and helps keep your line exactly where you intended.

The 641M-24 is also sized right for everyday bench work. The smaller format is easy to grab for drawer parts, face frames, boxes, cabinet parts, and machine setup tasks where a larger square just gets in the way. If you spend most of your time working with smaller parts or want a square that can ride in an apron or stay close on the bench, this size makes a lot of sense.

Woodpeckers also includes a wall-mountable Rack-It for storage, which is more useful than it sounds. Precision layout tools tend to get knocked around when they are tossed in drawers, and that is exactly what you do not want with a square this accurate. Keeping it stored upright and protected helps preserve the tool and keeps it ready for the next job.

This metric woodworking square is best for cabinetmakers, furniture builders, serious hobbyists, and anyone doing fine layout where repeatability matters. If your work depends on joinery fitting right, machine settings being trustworthy, and reference lines actually meaning something, this square earns its place fast. If you just need a rough construction square for site work, this is more tool than you need. If you care about exact setup and clean layout, it is exactly the point.

Woodpeckers 641M-24 641 Square, 150mm for Woodworkers Who Actually Care About Setup

This is a compact precision square that makes daily layout and machine setup faster, cleaner, and more trustworthy.

• Who it's for: Woodworkers, cabinetmakers, furniture builders, and serious DIY users who want a true metric layout square for bench work and machine setup.
• Why it stands out: The cast and ground aluminum construction, precision-pinned cheeks, hands-free shoulder registration, and very tight stated scale accuracy put it in a different class than basic stamped squares.
• Worth knowing: This is a small 150mm square, so it is best for close work and setup tasks, not large panel layout. The included Rack-It is worth using because a precision square should not live loose in a drawer.

• Is this the metric version? Yes. The 641M-24 is the 150 mm metric version of the 641 Precision Woodworking Square.
• What is this square designed to do? It is designed for accurate layout, machine setup, and assembly work in woodworking applications.
• Are the scales marked on both sides? Yes. Woodpeckers states that the scales are laser engraved on both sides of the blade.
• Is a storage rack included? Yes. This model includes a wall-mountable Rack-It.
• Where is it made? Woodpeckers says these Precision Woodworking Squares are built in the USA in Strongsville, Ohio.