Slotted Hand Screws with Reduced Shank Hand Tighten Slotted Captive Thumb Screw

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What Are Hand Screws?

A hand screw, also known as a woodworking clamp or carpenter’s clamp, is a traditional, versatile type of clamp primarily used in woodworking. It is characterized by its distinctive design featuring two wooden jaws connected by a pair of long, threaded steel screws. The screws operate in tandem, allowing the user to open, close, and align the jaws with a high degree of control. The parallel jaws provide excellent, even pressure across a wide surface without marring the workpiece, making them indispensable for gluing up panels, assembling frames, and holding projects securely in place.

Materials

The primary materials used in the construction of hand screws are:

• Jaws: Traditionally made from hard, durable woods like Maple, Beech, or Ash. These woods are chosen for their strength, stability, and resistance to warping.

• Screws and Nuts: Manufactured from hardened steel to ensure strength, durability, and smooth threading. The screws must resist bending under significant pressure.

• Handles: Typically made from the same hardwood as the jaws or from a robust plastic composite on modern models, providing a comfortable and secure grip.

Surface Treatments

Hand screws receive various surface treatments to enhance durability and performance:

• Wooden Jaws: Often treated with a boiled linseed oil or a varnish finish. This protects the wood from moisture, glue squeeze-out, and general wear, while also making the jaws easier to clean.

• Metal Components: The steel screws and nuts are usually coated with a protective lacquer or a black oxide finish to prevent rust and corrosion, ensuring smooth operation over many years.

Specifications

Key specifications for hand screws include:

• Jaw Length: Ranges from small 6-inch clamps to large 24-inch or even 36-inch models for substantial projects.

• Throat Depth: This is the distance from the edge of the workbench to the clamp’s screw, determining how far into a project the clamp can reach. It is typically equal to or slightly less than the jaw length.

• Maximum Opening: The widest distance the jaws can be opened, determined by the length of the steel screws.

Application Fields

Hand screws are exceptionally versatile and are used in:

• Woodworking and Carpentry: Their primary domain, perfect for gluing panels, edge-joining boards, assembling cabinets and drawers, and clamping irregular shapes.

• Furniture Making and Restoration: Ideal for applying even pressure without damaging valuable antique wood surfaces.

• Metalworking: Used to hold pieces in place for welding or soldating, as the wooden jaws will not conduct heat or mar metal surfaces.

• General DIY and Craft Projects: Useful for any task requiring a secure, non-marring hold.

An Excellent Case: Gluing Up a Wide Tabletop

A classic and excellent use case for hand screws is the glue-up of a wide wooden tabletop from multiple boards.

A woodworker has prepared several planks of maple, jointed and planed them to perfection, and is ready to glue them together to form a seamless tabletop. They lay out the boards on their workbench with protective cauls placed underneath. After applying glue to the edges of each board, they carefully bring them together.

They then use several large hand screw clamps, positioned strategically above and below the tabletop assembly. The independent operation of the two screws on each clamp allows the woodworker to perfectly align the jaws parallel to the wood surface. As they tighten the clamps, the wide wooden jaws distribute immense pressure evenly across the entire width of each board, preventing them from bowing or buckling under the force.

The non-marring wooden jaws ensure that the pristine surface of the maple shows no clamp marks or damage after the glue has cured. The result is a perfectly flat, strong, and visually flawless tabletop, a testament to the precise and gentle yet powerful clamping ability of the hand screw.