A Guide to Edge Clamps

Edge clamps, as their name implies, are for gripping the side of a part to keep the top clear for machining. Like other clamps, edge-gripping clamps are made in a variety of styles.

Serrated Edge Clamps. The serrated adjustable clamp, shown in Figure 8-60, is a common form of edge clamp. These clamps transfer the motion of an internal thread into a sliding motion that moves both forward and down along a 45º angle. The mounting slot is slightly angled to prevent movement of the clamp body away from the workpiece under heavy forces. The fixed version, Figure 8-61, is usually best for permanent fixtures because it mounts in a fixed position, rather than having a slot for adjustment. This allows the clamp to be more compact, and ensures correct position without adjustment. The Flat-Head Socket Screws used for mounting absolutely prevent slippage. These clamps are made with either a low nose or high nose. Both types have gripping serrations on the clamping jaws. These clamps have a V-groove in nose, which is useful for clamping round parts or corners. They have a large clamping range. The high nose version is best for most applications. Gripping high up on the workpiece, close to the cutting plane, provides maximum clamping rigidity. The high-nose version includes a removable aluminum nose cover for clamping soft or machined parts without damage. The low nose version is ideal for thin parts and other applications where extra machining clearance is required.

TINY VISE® Edge Clamps. These mini edge clamps grip the side of a workpiece to keep the top clear for machining. Their patented design features a slotted countersink to provide strong, reliable clamping force with the easy turn of a hex wrench, Figure 8-62. These compact clamps are ideal for fixturing multiple parts, small or large. Each clamp has both a serrated face (for maximum gripping) and a smooth face (to avoid marring finished parts). The clamps can be set up to apply force either at a downward angle or straight horizontally, as shown in Figure 8-63. All clamps are supplied with an optional bottom thrust washer. Installing this washer under the clamp will raise the clamp slightly and provide downthrust force during clamping. If no downthrust force is required, install the clamp without the bottom thrust washer. Doing so will improve clamping speed because fewer screw turns are required. The Tiny Vise® is also available with a V configuration, Figure 8-64. The V-jaw version is ideal for clamping round workpieces. The 90° V jaw can also be used to clamp a rectangular workpiece from two directions with a single clamp at its corner. Tiny Vises® are also available in double-sided versions, Figure 8-65, either with or without serrations, and also in a V-jaw version.

Tiny Vise® edge clamps are also available in a modular design, Figure 8-66. This version allows adjusting the workpiece engagement point by adding or removing spaces. This is useful when using the same fixture for machining a family of parts, or when workpiece size can vary somewhat between batches.

Pivoting Edge Clamps. Another edge clamp, shown in Figure 8-67, is the pivoting edge clamp. Rather than using an angular ramp to apply the holding force, these clamps have a pivot that directs the force. As shown, these clamps are often used with a matching backstop unit to securely hold the workpiece between two jaw elements.