V-block

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V-blocks are precision metalworking supports that hold round workpieces, like rods or small pipes, during drilling or milling. A steel or cast-iron block has a top V-shaped groove: 120 degrees, rotated 45 degrees from the block’s sides. A small groove runs along the bottom of the V. Many V-blocks include screw clamps to secure the work, and some have built-in magnets for magnetic holding. They are typically sold in pairs.